Difference between revisions of "Rice (incl. transport guidelines)"
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At harvest, paddy rice has a moisture content of generally between 20% and 28%. Most of paddy varies with maturity, whether it is rainy or dry season, and atmospheric humidity. The moisture content of paddy can very and is understandably higher in the wet season than in the dry season. <br><br> | At harvest, paddy rice has a moisture content of generally between 20% and 28%. Most of paddy varies with maturity, whether it is rainy or dry season, and atmospheric humidity. The moisture content of paddy can very and is understandably higher in the wet season than in the dry season. <br><br> | ||
Paddy rice should be dried to a moisture content of less than 20% within 48 hours of harvest to reduce the chances of damage. To facilitate good storage, it is best that the paddy rice is dried in the sun or with modern drying techniques and/or machinery to a moisture content of 14% or less. <br><br> | Paddy rice should be dried to a moisture content of less than 20% within 48 hours of harvest to reduce the chances of damage. To facilitate good storage, it is best that the paddy rice is dried in the sun or with modern drying techniques and/or machinery to a moisture content of 14% or less. <br><br> | ||
− | Rice kernels should have a moisture content of between 13% and 14% to ensure good storage. When the moisture level exceeds 14%, the rice takes on a yellowish hue that can | + | Rice kernels should have a moisture content of between 13% and 14% to ensure good storage. When the moisture level exceeds 14%, the rice takes on a yellowish hue that can lead to mould, lumping and decay and can result in damage affecting both the quality and quantity of the rice. <br><br> |
The damaged rice can affect undamaged rice in close proximity but not necessarily in direct [[contact]], particularly when bagged and awaiting shipment. Therefore it is prudent to check for this type of damage prior to the cargo leaving the warehouse storage facility.<br><br> | The damaged rice can affect undamaged rice in close proximity but not necessarily in direct [[contact]], particularly when bagged and awaiting shipment. Therefore it is prudent to check for this type of damage prior to the cargo leaving the warehouse storage facility.<br><br> | ||
In order to do so, the carrier and their appointed surveyor require the full cooperation of shippers to identifying where the rice is being stored prior to shipment. <br><br> | In order to do so, the carrier and their appointed surveyor require the full cooperation of shippers to identifying where the rice is being stored prior to shipment. <br><br> | ||
The favourable travel temperature of rice is 5 – 25°C. The optimum temperature for the development of moulds is between 20 and 30°C. Travel temperatures of >25°C increase metabolic processes and thus self-heating and agglomeration (sticking together). | The favourable travel temperature of rice is 5 – 25°C. The optimum temperature for the development of moulds is between 20 and 30°C. Travel temperatures of >25°C increase metabolic processes and thus self-heating and agglomeration (sticking together). | ||
+ | |||
===Milling and processing=== | ===Milling and processing=== | ||
Rice processing is the most essential stage of the post harvest activity where husks and bran particles are removed from the paddy grain. Milled rice maintains a higher temperature than that prior to processing. Generally, at this stages the moisture content is higher than 14% and particles of bran adhere to the surface of the kernel. Since the rice has generally been whitened, it soon takes on an ivory or yellow coloration. | Rice processing is the most essential stage of the post harvest activity where husks and bran particles are removed from the paddy grain. Milled rice maintains a higher temperature than that prior to processing. Generally, at this stages the moisture content is higher than 14% and particles of bran adhere to the surface of the kernel. Since the rice has generally been whitened, it soon takes on an ivory or yellow coloration. |
Revision as of 10:29, 18 January 2021
Infobox on Rice (incl. transport guidelines) | |
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Example of Rice (incl. transport guidelines) | |
Facts | |
Origin | This table shows only a selection of the most important countries of origin and should not be thought of as exhaustive.
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Stowage factor (in m3/t) |
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Angle of repose | - |
Humidity / moisture |
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Oil content | - |
Ventilation | Loading as bulk cargo: surface ventilation. Loading as general cargo: air exchange rate 15 - 25 changes/hour. Good surface ventilation and airing are necessary. |
Risk factors | At an excessively high water content in particular, rice has a tendency towards self-heating. Water contents of > 15% and relative humidities of > 75% result in self-heating of the cargo due to hydrolytic/enzymatic fat cleavage. Rice is highly odor-sensitive, prone to contamination and shrinkage. Beware of infestation. |
Rice (incl. transport guidelines)
Contents
Transport guidance on bagged rice
As a cereal grain, rice is the most important staple food for a large part of the world's human population, especially in Asia and the West Indies. It is the grain with the second-highest worldwide production, after maize (corn).
Since a large portion of maize crops are grown for purposes other than human consumption, rice is the most important grain with regard to human nutrition and caloric intake, providing more than one fifth of the calories consumed worldwide by the human species.
Therefore we have extended the article on rice to a transport guidance, in order to prevent loss as much as possible.
Introduction
Types of rice cargoes
Rice, or Oryza, can vary in height from 1 – 6 m. It is an extremely adaptable plant; it has an efficient system of air passages connecting the roots and the shoot. This enables it to grow in dry upland soils, in irrigated fields, or along flooded river beds. Rice is largely self-pollinated, but cross-pollination does occur in degrees ranging between 1 – 30%.
There are over 85.000 varieties of rice in the research stocks of the International Rice Research Institute (IRRI), and there are over 120.000 cultivars known to exist. The familiar distinctions to Westerners of long grain versus short grain, or white versus brown, are but two. Like wheat, oats or maize, rice is a cereal. It is a basic diet for over 50% of the world’s population and is therefore the most important crop in the world. The range of varieties is so great that no internationally recognised system of classification exists, although repeated efforts have been made since the Rice Congress at Valencia in 1914 urged ‘the formation of a real botanical classification of the varieties of cultivated rice’. Two species are cultivated, Oryza sativa and Oryza glaberrima (wild rice – in West Africa).
Asian rice, Oryza sativa, is divided into two categories, both of which include glutinous and non-glutinous varieties. Indica rices’ grains are longer and more slender, and they usually remain separate when cooked. Japonicas have shorter, rounder and more translucent grains which quickly become slightly sticky. Indica grains are divided into medium (5 – 6 mm) or long grain (more than 6 mm). It was proposed in 1958 to coin another name, javanica, for the bulu and gundil varieties of Indonesia. Most rices grown in the tropical zones belong to the indica and javanica groups, which tend to have a fixed growth period. Japonia rices have shorter grains (4 – 5 mm) and are also different in terms of taste and smell. They are highly sensitive to photoperiod, or day length, and so do poorly in the short-day tropics. They are, however, widely grown in N. China, Korea and Japan. Then there is glutinous rice, (Oryza sativa L. glutinosa) which is specified as having a starch level of 99$ amylopectine. The grains are completely opaque, and this rice tends to be reserved by Asian populations for confectionery and cakes.
The long grain varieties, Oryza indica, tend to be preferred by the people of Inda and SE Asia; the Japanese and Indonesians prefer the stickier, short grained variety Oryza japonica.
Rice plants are usually grown in flooded fields known as paddies, although there are varieties which can be grown ‘dry’, for example in Tanzania, Zambia and the Philippines – these tend to produce a lower yield, however. The roots of the rice plants are kept underwater. The head of the plant, known as the panicle, contains small spikelets which produce grains of raw rice, known as paddy.
Before the paddy field is flooded, the soil needs to be broken up and levelled. In most rice-growing countries, the seeds are first sown in nurseries. Small corners of the paddies are set aside for sowing. On the first night, the seeds are often kept in water, to allow germination, then planted. About 30 days later, the rice plants are pressed into the mud in rows. The rice plants are often under attack from weeds or pests such as rats, worms, birds and snails – hence there are often fish in the paddy fields. Fish are no protection, however, against the other threats of hurricane, drought or rats.
Rice matures very quickly in the right growing conditions. The life cycle of the rice plant is generally 100 – 210 days; the average falls between 110 – 115 days. In temperate climates the average duration from sowing to harvest is about 130 – 150 days. Cultivars with growth duration of 150 – 210 days are usually photoperiod sensitive and are planted in the deepwater areas. Temperature and day length are the two environmental factors affecting the development of the rice plant, which can be divided into three phases:
- Vegetative – from seed germination to panicle initiation;
- Reproductive – from panicle initiation to anthesis;
- Ripening – from anthesis to full maturity.
Controlled irrigation dramatically improves yields – most rice needs between 250 – 600 grams of water for each grain of rice eventually formed. When ready for harvesting, rice is a golden yellow.
Combine harvesters can cut the rice, separate the grain from the straw, and leave the straw in the field.
When harvested, rice typically contains from 15 – 22% (US) or 19 – 25% (Asian) moisture and therefore must be dried to a moisture content of 12 – 14% to prevent spoilage. The rice dries in the sun, or it can be dried by blowing hot air through piled sacks of grain, which reduces the risk of disaster from sudden torrential rain. Paddy is then stored to protect it from damp, heat, rodents, insects, birds and fungi; it can be stored in large pots or bamboo baskets, or in lofts or barns on stilts. Rice can be stored for years. Modern steel or concrete silos automatically control the humidity and temperature of the vast amounts of paddy which they contain.
After being dried and stored, the rice goes through the milling process, which removes the tough outer husk and inner layers of bran from the edible rice grain. Unfortunately, milling also removes much of the goodness, hence the gradually increasing demand for brown rice. However, most consumers like white rice, so the grain is also polished white, and sometimes also glazed with glucose and talc. From 100 kg of paddy (rough rice), 20 kg of husk and 80 kg of brown, de-husked rice can be obtained. From the milling process, 68 kg of milled rice (or parboiled rice, where the rough rice is exposed to steam pressure and the grain becomes harder and less sticky) and 12 kg of bran and other by-products are obtained. From the 68 kg, 55 kg can be expected to be wholegrain and 13 kg broken grain.
Rice is traded either as paddy or milled rice and an indication is needed in the description of the product i.e. paddy/brown/milled/parboiled. Other mentions needed are grain type (long or short), origin and the percentage of broken rice, for instance, Thai white rice long grain 5% broken.
Electronic sorting machines can classify the size, type and colour of each batch of rice and separate the different grades for packaging. The main patterns of good quality are:
- Colour – as white as possible (no discolouration, no imperfections);
- Whole grains – minimum percentage or broken grain.
Standards in most countries define the percentage of brokens and other imperfections allowed in each grade of rice, and the basis on which such percentages are measured.
Composition and nutritional value
The composition and nutritional value of rice varies with the nature of the soil, climate, variety, the conditions of culture – in particular the fertilizers used, etc; this it has in common with all vegetables and grains. But for rice in particular, the nutritional value depends on the degree of milling that is undertaken. Brown rice contains 8% protein, 70% starch and small quantities of lipids, fibre and minerals. After milling, however, the decline in beneficial elements is dramatic, see Table 1.1. This shows a dismal picture indeed when one considers the social, economic and, above all, taste pressure which encourages the milling of rice. The reasons for the dramatic fall in nutritional value after milling are as follows:
The starch is found principally in the endosperm; the lipids, fibres, vitamins and minerals are concentrated in the cellulose layer. Glucose molecules are found in two forms; amylase and amylopectine, the proportion varying between varieties. Most current varieties contain 12 – 35% amylase, the rest being amylopectine. Glutinous rice is low in amylase and tends to stick together in cooking. Simple sugars such as sucrose are present in brown rice in the 0,6 – 1,4% range, and in white rice from 0,3 – 0,5%. Fibre is present in the shell of brown rice but hardly at all anywhere else and therefore only marginally in white rice. Proteins, the second major constituent of rice, are present in the endosperm in the form of 1 - 3µm granules but these are eliminated in the milling process. Of 17.600 varieties of rice analysed by the IRRI, the percentage of protein varied from 4,3 to 18,2% with a middle point of 9,5%. Table 1.2 shows the amino acid content of the different forms and elements of IR-8.
Table 1.1 - Effect of refining and parboiling on rice, 100 g.
Energy, Kcal | |||
Protein, g | |||
Lipids, g | |||
Fibre, g | |||
Cendres, g | |||
Thiamine, mg | |||
Riboflavin, mg | |||
Niacine, mg |
Table 1.2 - Amino acid content of the different forms and elements of IR-8 - g/16,8 gN
Amino acid | |||||
Isoleucine | |||||
Leucine | |||||
Lysine | |||||
Met + Cys | |||||
Phe + Tyr | |||||
Threonine | |||||
Tryptophane | |||||
Valine | |||||
Chemical score | |||||
Proteins | |||||
Proportions by weight | |||||
Distribution of proteins | |||||
Tryptophane |
A 100% = 3,76 g Met + Cys/16,8 gN
B 100% = 5,78 g Lys/16,8 gN
Source: IRRI
Brown rice has 1,8 – 3,9% lipids, concentrated in the aleuron and embryo. Most is in the bran; polished rice contains only 0,3 – 0,7% lipids. These are used industrially (a.o. rice oil for animals and soap products).The mineral value of rice is another factor which is adversely affected by milling, see Table 1.3.
Table 1.3 - Mineral value of rice, mg/kg
Calcium | ||
Phosphate | ||
Iron | ||
Sodium | ||
Potassium | ||
Zinc |
Source: IRRI
There is not much iron, and half is in the part removed by milling. The ratio between calcium and phosphate is not ideal; the phosphate is found mainly in the form of phytates.
The level of vitamins A and D is negligible, although there is a great deal of vitamin E. There is little riboflavin (0,6 mg/kg in brown rice), and virtually no vitamin C, but there is ample thiamine (3,4 mg/kg of brown rice) and niacine (52 mg/kg of brown rice) as well as pyridoxine and panthotenic acid. An average serving (6 oz) of cooked rice gives enough energy to walk for 45 minutes, because it contains 345 kcal per 100 kg, which is almost identical to wheat and maize (340 and 342 respectively). This is for 100 g of dry rice, of course, and after cooking rice triples its volume. 100 g of cooked rice contains 120 cal, 3 g of proteins, 0,1 g of lipids, 0,01 mg of thiamine and 3,4 g of niacin. Bran and ‘polish’ together contain about 85% of the oil, 10% of the protein, 80% of the thiamine (B1), 70% of the minerals and fibre, 50% of the riboflavin (B2) and 65% of the niacin of the whole grain. White rice is 90-94% pure starch and when highly polished contains only 7% protein by comparison to 10% for brown rice. Based on 100 g portions, the caloric content of cooked rice is 111 for brown rice, 109 for regular milled and 106 for parboiled. Rice is a complex carbohydrate, supplying energy over long periods. Another important function of a dietary carbohydrate is energy sparing – the body does not use protein to meet energy needs when a carbohydrate is available. The protein content of rice is of good quality because it contains all the amino acids necessary for human life; it contains only a trace of fat and is cholesterol free; it is non-allergenic and gluten-free, and is very low in sodium. Rice starch is almost completely digested, and between 65 – 88% of rice proteins are digested, depending on how adult the person is – children do not absorb rice proteins as effectively. A number of studies have been carried out on the optimum addition of proteins to a predominantly rice-based diet, and in general it appears to depend on the type of rice being consumed so that general indications are hard to draw.
As a food, it contains all the carbohydrate that individuals need in their diet, being 90% carbohydrate itself/ Dry rice produces 3,5 kilocalories per gram, compared with 8 kcal for a gram of fat. Rice is a good source of various B group vitamins such as thiamine (B1) which helps control various body functions, the human nervous system, and also contributes to healthy skin. B group vitamins are water-soluble and cannot be stored in the body; therefore a regular intake is essential. Natural brown rice is an excellent source of dietary fibre which performs many vital functions within the human body; it eases the disposal of waste products and is also easily and quickly digested, making it especially suitable for athletes, babies and the elderly.
Most specialist doctors believe that the fibre in foods like brown rice plays an important role in prevention of diseases such as diabetes, heart disease and cancer of the colon. In the past, fibre was thought to add bulk to food but to have little other benefit. Now it is widely recognised that it is a far more complicated substance and is not digested by human beings. The indigestible fibre passing through the bowel can reduce the amount of fat absorbed by the body from fatty foods. It can also help slow down the rise in blood glucose after a meal, particularly beneficial to people within diabetes who need to control their blood sugar levels. Brown rice however, takes up to 40 minutes to cook, compared to less than ten for milled white rice, which is inconvenient for many people.
Rice does, however, provide insufficient protein on its own for a healthy diet. Moreover, the loss of real food value caused by the milling process makes it little short of a world tragedy that the preferred consumption of rice is in its milled, white, highly polished form, when it is easier to eat and quicker to cook. Malnutrition, especially in infants, causing protein deficiency, beri-beri, iron and zinc deficiency, is common in countries where rice forms an overwhelming percentage of the population’s diet. Beri-beri has increased since the increase in use of mills, and was common in Thailand in the 1970s. It is only the increased income of the country in general that has led to alternative foods being available in that country since then, which has cut the problem dramatically. Adding riboflavin to rice causes discolouration, which has dissuaded Far Eastern eaters. There is clearly a need to increase the supplementary elements to a rice-based diet, for example meat, milk, eggs and above all fish, and vegetable oils; to increase the amount of parboiling, and of brown rice to be eaten.
Malnutrition problems are actually exacerbated by the introduction of efficient mechanised units due to the more efficient milling. One way of avoiding the loss of nutrients during milling is first to parboil the raw paddy rice. Parboiling involves transferring the proteins and vitamins from the bran layers to the white central part of the seed, by steeping the paddy in hot water, steaming it and drying it before milling. This procedure gelatinises the starch in the grain, and ensures a separateness of grain. Parboiled rice is favoured by consumers and chefs who want a fluffy, separate cooked rice. It retains more nutrients than regular-milled white rice, but takes a few more minutes to cook.
It is possible to restore valuable nutrients after milling by adding solutions of thiamine, niacin, iron and riboflavin. Enriched rice has greatly helped to improve the problem of malnutrition in many rice-eating countries. Rice is a very palatable cereal; the only one which can simply be boiled and eaten without degenerating into mush.
Food and animal feed uses
Rice is used almost exclusively for human consumption; hardly any is used as animal feed. In all Asian countries, China, India and Bangladesh in the East and Japan and Korea in the South, rice is the most eaten cereal by far. Average annual consumption is about 100 kg per person with a wide variation between countries. In Vietnam it reached 240 kg per person in the 1980s. In Laos and Thailand 202 kg, in Bangladesh 160 kg, whereas in the Philippines it was 89 kg, in India 73 kg and in China estimates vary from 72 – 96 kg/person. The variations are accounted for by the use of other cereals. These levels compare with 4 kg annually per person in France, for example.
The types of rice in which each market is interested vary enormously, which is a factor of great significance for the international rice trade itself. Sadly, much of this trade involves shipping rice to countries that already grow it because the national tastes do not suit the particular type grown.
Two very good examples of this practice are the export of round grain rice from Italy and the import of long grain rice; and the import of fragrant Thai rice into California. In both cases, domestic rice production is slowly changing to meet the changes in demand, but it must be realised that the types of rice demanded can vary so much that one form of rice can be completely unacceptable to one market. For example, the Japanese market, at least for the time being, prefers white short grain rice, recently milled, of a japonica variety. The Thais, by contrast, prefer a well-milled rice, stored for some time, of a long grain indica easily separable variety.
Again, Middle Eastern consumers prefer long grain rice with a strong taste, whilst Europeans prefer tasteless long grain rice. Africans prefer broken rice, especially of the red tinted type. Bangladeshis prefer parboiled rice which is easily cooked. One regrettable but abiding fact is that brown rice is little appreciated in tropical countries. In hot countries brown rice keeps badly, but the real reason is that brown rice symbolises poverty in these countries, people try to avoid it, and it is considered inappropriate to serve it to guests.
Unlike other cereals, rice is usually presented to the consumer in its raw form, so it is according to visual criteria that rice is judged – the length of the grain, the degree of whiteness, the translucence, the proportion of broken grains and so on. The EC distinguishes four types of rice on the basis of the ratio of the length to the breadth of the grain, see Table 1.4.
Table 1.4 - Grain types
Round grain | ||
Middle grain | ||
Long grain A | ||
Long grain B |
Source: ONIC
The cooking qualities of rice are largely determined by the relative quantities of amylase and amylopectine in the starch and to a lesser extent by the level of proteins and the temperature of gelatinisation. The more amylase, the better the rice stays apart when cooked. Less than 20% between 20 – 25% and 25 – 36% are the three classes in this matter. Indica rice consumers in India, Pakistan, Bangladesh, Malaysia and South China prefer varieties high in amylase, i.e. a ‘dry’ rice after cooking, whereas in the Philippines and Indonesia, intermediate levels of amylase are preferred, and the Japanese and North Chinese choose ‘sticky’ rice. In North Thailand and Laos, glutinous rice is preferred. Parboiling, practised largely in India, Bangladesh and Sri Lanka, produces a further set of distinguishing characteristics largely appreciated in those countries only. It is however, worth adding that in western countries a growing appreciation of all types of rice is now occurring, and even Thai fragrant rice can now be bought in the average British supermarket – an extraordinary change from the 1970s when only long grain US rice was available, apart from short grain rice contained in deserts.
Rice is now eaten in almost every country in the world. For example, it is used in Spanish paella, the popular US dish of jambalaya and with curry in virtually every Asian country and the U.K. Rice is also eaten toasted or coated with sugar or chocolate as a breakfast cereal. Rice can be eaten on its own, or coloured with saffron or turmeric, or flavoured with herbs and spices. For example, pilau rice is made by adding peppers, stock and onion. Rice is also used to make powerful alcoholic drinks, for example, saki (Japan) and wang-tsai (China) come from rice. Almost one-third of the rice used in the USA goes to make beer.
Rice must be cooked before the human body can absorb the starch. There are basically four ways in which rice is cooked: with just enough water, by boiling in a large quantity of water and draining, cooking in fat (as with paella, risotto and pilaff) and steaming. The temperature necessary for cooking rice depends on the starch and protein composition of rice: ordinary white rice takes about 16 minutes to cook (less in a microwave oven). Rice increases in size from 100 kg to 230 – 240 kg after cooking. This capacity for retaining water actually poses a problem for infant nutrition: the infant stomach can retain only 180 ml at 2 years, so to get 1000 kcal of energy, it would be necessary for the infant to ingest about 1 kg. However, it is possible to reduce this absorption by introducing other cereals into the cooking. To reduce the time taken in cooking, pre-cooked rice has been put on sale, which has reduced cooking time to only a few minutes.
Ground rice flour is used to thicken sweets and sauces, and to replace wheat flour in the diet of people who suffer from food allergies. Wheat flour loaves are often dusted with rice flour before baking, and powdered rice is used in some developing countries to make noodles, cakes and sweetmeats. Rice paper is also used to cook cakes and sweets such as macaroons; rice bran is used for animal feed. The stubble from rice is ploughed back. The straw is used for making hats, shoes, ropes, mats and for thatching. The surplus straw is used as animal fodder and bedding. Rice husks, removed by milling, have little nutritional value but they are very rough and contain silicon, which is useful as an industrial abrasive. The husks are used as fuel in village stoves, as insulation, for making lightweight brocks and as a packing material. New uses are constantly being researched for the 75 m tonnes of husks produced every year. Rice is also used for starch production, glucose, rice vinegar and rice oil.
By contrast, the bran has a very high nutritional content. It can be refined to make a fine, clear oil, low in fatty acids, which is good for cooking and for protecting industrial machinery from rust. Broken rice is bought by brewers, who use it to make liquors such as saki and arrak. Whole and broken rice is used for making starch. Tinned pet foods and sausage fillings often contain a percentage of broken rice. It is evident, then, that rice has a variety of nutritional, feed and other uses, vital to the lives of billions of rice consumers across the world. It is important to realise how essential rice is.
Rice qualities traded
Paddy: usually with a guaranteed milling yield such as 55 – 68 meaning that out of 100 kg of paddy the miller will obtain after milling 55 kg of white grains and 13 kg of broken grains, giving a total yield of 68 kg. Only a few countries, notably the USA, export their paddy rice.
Brown (dehusked): usually required by the rice industry with a guaranteed yield, e.g. US 2/4/73 – 73% whole grain, 12% bran and 15% brokens.
Some commercial rice mills are in the rice producing countries such as Indonesia; others are in the rice consuming countries, including Britain and Holland which import raw paddy for their mills.
Of milled rice, the most widely traded qualities are:
White:
- US milled No. 2/4 long grain (grade 2/4% brokens) to Europe/Middle East/Latin America
- US milled 5/20 LG (grade 5/20% brokens) in US foods aids
- Thai White Rice 100%B (4,5% broken maximum) to Middle East (Iran/Iraq), Malaysia
- TWR 5/10/15/25/35% brokens
- Broken 100% either for human consumption or as animal feed
Parboiled:
- Thai parboiled 5% brokens to Benin/Nigeria/Bangladesh
Most of rice moving in world trade is fully milled and bagged. Packaging requirements in contracts may be anywhere from a shipload full of bulk (loose) rice to 1 kg retail boxes, but 50 kg (or 100 lb) bags being common sizes. The international rice trade is under a quarter of that in wheat, which trades almost 20% of tits world production. However, in value terms the rice trade is closer to wheat – approximately one quarter – about half of the sugar trade and almost as much as the cocoa trade.
Definition of 'rice'
‘Rice’ shall mean: rice, rice products, and rice by-products. It shall include: milled rice, brown rice, undermilled rice, parboiled rice, pre-cooked rice, rice flour, rice bran, rice polish, rice hulls, rice mill feed, and any other rice products or by-products.
The rice trade
Recent statistics show a total amount of rice traded globally was 23 million tonnes. The ratio of trade volume, against a total production (340 million tonnes of milled rice base) is approximately 6,5%, which is significantly less than other grains.
Rice production in Vietnam is about 34 million tonnes (paddy base) where the main production areas are the Mekong Delta in the South and the Red River Delta in the North. The Mekong Delta produces more than half of the country’s total production and provides suitable climate conditions where in most cases farmers can harvest rice more than 3 times a year.
Rice harvests are generally between February and March; July and August; November and December for short time rice; and January and February for long time rice.
Rice moisture
At harvest, paddy rice has a moisture content of generally between 20% and 28%. Most of paddy varies with maturity, whether it is rainy or dry season, and atmospheric humidity. The moisture content of paddy can very and is understandably higher in the wet season than in the dry season.
Paddy rice should be dried to a moisture content of less than 20% within 48 hours of harvest to reduce the chances of damage. To facilitate good storage, it is best that the paddy rice is dried in the sun or with modern drying techniques and/or machinery to a moisture content of 14% or less.
Rice kernels should have a moisture content of between 13% and 14% to ensure good storage. When the moisture level exceeds 14%, the rice takes on a yellowish hue that can lead to mould, lumping and decay and can result in damage affecting both the quality and quantity of the rice.
The damaged rice can affect undamaged rice in close proximity but not necessarily in direct contact, particularly when bagged and awaiting shipment. Therefore it is prudent to check for this type of damage prior to the cargo leaving the warehouse storage facility.
In order to do so, the carrier and their appointed surveyor require the full cooperation of shippers to identifying where the rice is being stored prior to shipment.
The favourable travel temperature of rice is 5 – 25°C. The optimum temperature for the development of moulds is between 20 and 30°C. Travel temperatures of >25°C increase metabolic processes and thus self-heating and agglomeration (sticking together).
Milling and processing
Rice processing is the most essential stage of the post harvest activity where husks and bran particles are removed from the paddy grain. Milled rice maintains a higher temperature than that prior to processing. Generally, at this stages the moisture content is higher than 14% and particles of bran adhere to the surface of the kernel. Since the rice has generally been whitened, it soon takes on an ivory or yellow coloration.
Preparing rice for export
World trade figures are very different, as only about 5–6% of rice produced is traded internationally. The largest three exporting countries are Thailand, Vietnam, and the United States. Major importers usually include Bangladesh, the Philippines, Brazil and some African and Persian Gulf countries. Although China and India are the two largest producers of rice in the world, both countries consume the majority of the rice produced domestically, leaving little to be traded internationally.
Thailand will continuously lose competitiveness and export market share to Vietnam in Asean and other markets over the next 10 years due to that country's clearcut policy of developing its rice production and marketing, according to a report by the International Trade Studies Centre.
In 2020, Thai rice exports to the world market are projected to drop by 14 per cent from this year's level to 8.6 million tonnes, while Vietnamese exports will surge by 25 per cent to 7.5 million tonnes.
Prior to the 1990’s Vietnamese rice exports were considered low grade where on the order of 35% of exported rice had broken ends. Following significant improvements in production and processing technology, Vietnam can produce rice with between 5% and 10% broken ends.
There is a Vietnamese Rice Standard for Export that was established by the Standardization Meteorology and Quality Control (SMQC) Centre. Foreign buyers can require the Vietnamese standard or request their own export specifications. The following steps are indicative of how local exporters prepare rice for export:
- Milled rice is purchased from local mill/merchant
- The rice is processed and/or classified according to the grades and standards for export. Cargo is separated into separate piles according top grade and quality.
- Adjust the rice quality, if necessary, to meet the specifications of the shipments by reprocessing (via whitening, sieving, polishing, drying, etc.) or simply by mixing rice of different quantities from separate piles in ratios determined during packing at the warehouse.
- Bagged rice is transported from warehouses and remote locations in and around Ho Chi Minh City and throughout the Mekong Delta area. This point makes if difficult to monitor the rice accurately.
Notable problems
Most rice exporters, sellers and shippers allocate quantities of cargo for one-day shipment to several supplier warehouses in Ho Chi Minh City and/or Mekong Delta provinces. Since these suppliers do not necessarily export directly, each supplier is solely responsible for their cargo until loaded into the ship. They then try to profit by supplying cargo just meeting the lower margin of the required specification and at times, slightly out of specification.
In addition, many suppliers buy rice from local farms, mills or merchants as needed due to lack of adequate finances to buy and process rice in advance of export. When cargoes are needed urgently for export, the rice cannot necessarily be processed in time resulting in compromises made with the cargo quality. This can result in compromising the cargo quality and, in particular, exceeding the necessary moisture content.
As mentioned earlier, the Vietnamese Government Standard for average moisture contents is 14%. This can easily be complied with by mixing rice kernels of higher moisture contents (e.g. 14,5%) with rice of low moisture content (e.g. 13%) at a ratio that makes the overall content meet the required government standard. However, the effects can be damaging during transport that leads to mould, discolouration and decay. It not only affects rice in close proximity, but other rice within the hold leading to moisture migration, smell, taint and heating of cargo. Damp rice kernels spoil undamaged rice in the immediate vicinity.
It is therefore important that, weather permitting, cargo and holds are adequately ventilated.
The problem of exceeding the moisture content is compounded during the country’s monsoon season between May and November. Moreover, to meet Vietnamese government specifications, many small suppliers and warehouses simply adjust the quality of rice by mixing it with rice from different quality, grade and moisture content during the packing operation. This method is acceptable for some contracts of quality such as meeting the percentage of broken kernels, red kernels, yellow kernels, paddy, etc. but is problematic when it neglects the moisture content of the rice.
While techniques in drying and processing rice have improved significantly over recent years, there are many loop holes in the system that allow poorer qualities of rice to be shipped with rice that meet quality standards.
Circumstances at the load port
It is normally the case that the ship’s holds are examined prior to loading by cargo interests. Shipper’s surveyor will normally request that a hose or preferably an ultrasonic test of the hatch covers is conducted. Ships’staff should cooperate fully with such requests.
If the ship is approved to load, then dunnage (timber or bamboo) will be placed on the tanktops of each hold. This is normally in the form of timber planks of cross sectional dimensions 6”oximately) which are laid longitudinally in a fore-and-alignment on the tanktop. Thereafter, kraft paper, or plastic sheeting will be laid on the top of the dunnage. (in some Vietnamese ports bamboo poles and matting are substituted for the timber and kraft paper/plastic sheeting, such as outlined under item ’4.1 Dunnaging’.
The objective of this is to separate the bags from the steel work of the holds in order to allow an air gap to:
1. Permit ventilation
2. Uplift the lower-most bags from the steel tanktop such that if condensation forms on the latter, it will not be in contact with the cargo and thus prevent wet damage.
3. Allow a drainage space for the condensation to flow aft to the bilge suctions.
This specification of protecting the bags does not achieve its intended objective as in between the planks the cargo will be separated from the hold tanktop steel plates by merely the thickness of the kraft paper or plastic sheeting. In this scenario, any formation of moisture from whatever source will almost certainly result in wet damaged bags above and such moisture will not be able to flow aft to the hold bilge suctions. What is needed is a cross pattern of stout timbers, the lower planks arranged fore and aft and the upper planks transversely. Thereafter the upper planks should be covered in either kraft paper or plastic sheeting before loading commenced. Similar arrangements should be arranged to prevent contact of the bags with the steelwork of the hold at the sides and fore and aft ends of the hold.
This of course is an expense for the account of shippers and/or charterers, which they will usually attempt to avoid. Often an inadequate degree of dunnaging (i.e. one tier of planks on the tanktop fore-and-aft) within a ship’s hold has been consistent with initiation/aggravation of wet damage. Masters should formally complain to Cargo Interests/Charterers with a letter of protest when inadequate dunnaging is provided.
Condensation during the voyage to West Africa will often occur as the ambient air temperature and the sea water temperature reduces. Additionally, day and night time air temperatures differ substantially more in non-tropical regions than in tropical regions. This will promote condensation if proper ventilation is impossible. Additionally, when the ship rounds South Africa and passes from the warm southern Indian Ocean waters into the cold Southern Atlantic Ocean waters there will be a substantial drop in sea water temperature. This cooling effect will also promote the development of condensation.
The solution is adequate ventilation and the provision of an air gap between the hold steel work and the cargo and adequate ventilation channels within the cargo stows. Most of the ships however, have no mechanical means of ventilation. It is known that some carriers elect to open the hatch covers during the voyage as much as possible and when conditions permit. It is not the intention of this book to discuss in detail when and how to ventilate cargo holds as the sciences is well established and accepted in the industry.
Many claims in West Africa concern wet damaged cargo to varying degrees in the lower tiers in every hold cause by condensation arising out of the factors outlined before. In most of such cases, locally appointed cargo interest’s surveyor insisted that irrespective of the fact that tiers above the lower most tier in each hold were in a sound condition, the wet damage to the lower most tier could only have been caused by sea water ingress via the hatch covers. Clearly, this is an irrational and unsustainable argument which can be defended albeit at considerable cost both to the ship owner’s P&I interests and to cargo underwriters. Most of these problems and costs can be avoided merely by adequate separation of the cargo from the hold steelwork and by the methods mentioned above.
It is in the interests of cargo shippers, receivers, charterers and the shipowners, that the minor additional expense of providing adequate dunnaging to the tanktop and ship’s sides during loading, as noted above, would considerably reduce cargo damage claims and survey costs incurred in investigating same.
Loading rice
Vessels customarily load rice cargoes at mooring buoys or anchorages in and around the port of Ho Chi Minh City. Bagged rice can be transported by truck from inland points or directly into wooden or steel barges and delivers the rice alongside the vessel. Cargo can be exposed to wetness damage during the barge leg of the voyage due to water ingress via the barge hull planking from older wooden barges or via the deck/hatch cover arrangements of both steel and wooden barges. This is a particular problem during inclement weather.
Cargo is loaded aboard using port stevedores who are not usually contracted by the owner but by the shipper and/or charterer. Experience has shown that little or no attention to detail or care is shown to loading the cargo since the stevedores are poorly paid for their work.
The use of steel hooks to load bagged rice is generally prohibited. However, this practice is still used and unless challenged will go on unabated. The consequences of such actions can result in damage and loss of cargo through spillage that doesn’t become evident until cargo is discharged.
At many West African ports where rice is discharged, receivers are often claiming that the bags and contents are damaged, even if the cargo is sound but the bag has but a small cut no longer than say 1 cm long. Clearly, if stevedores use hand hooks, then every bag perforated by such a hook during loading will be deemed damaged at the discharge port.
Hence, the Master must issue letters of protest to cargo interests, the mate’s receipts should be suitably claused and the agents given written instructions only to sign bills of lading in accordance with the clauses on the mate’s receipts. Additionally, many good photographs should be taken and made note of date, time and specific location, and also what the problem is that the photograph is attempting to portray. Such evidence is extremely valuable for Owner’s P&I club surveyor when attending at the discharge port.
It is not uncommon to see stevedores urinating in or on cargo in underwings and secluded corners of the vessel. Experience shows that the stevedores care little for safe stowage and dunnaging and building of ventilation channels in the stow that provide adequate ventilation of cargo. Consequently, shipowners, charterers or receivers will arrange for separate stevedores to arrange and lay appropriate dunnage.
Lowering heavy slings or drafts of cargo too fast on to cargo already in stowage may be responsible for damage, which often goes undetected until discharge. Similarly, forcefully dragging cargo out that is wedged by other cargo or even overstowed, may be another source of damage at the time of discharge. The use of cargo hooks may be indispensable in the handling of a large variety of break bulk commodities, but with bagged cargo the use of cargo hooks may be productive of much mischief and claims, and should be strictly prohibited.
It is recommended that shipowners arrange for independent surveyors to ensure proper stowage, care of cargo during loading. It is also recommended for ship’s staff to conduct initial, intermediate and final draft surveys to reduce chances of cargo shortage claims.
Ensure that owners have appointed an independent firm of tally clerks and that there is one at each hold tallying the cargo during loading. It is unadvisable to rely on charterers’ tally clerks. From time to time ships’ staff should check that the tally clerks are correctly counting the bags loaded. There is a practice at both the loading and discharge ports for tally clerks to count only the net slings loaded into the ship assuming that each has the ‘standard’ number of bags loaded into the sling. This may not be the case and often this is not the case in West Africa during discharge.
Where applicable, the hatches should be sealed upon completion of loading in the presence of the shippers/charterer and unsealed at the discharge port, in the presence of the receivers/charterer.
Ships’ staff should record details of superintendents attending the vessel, who they represent and record their loading instructions. If Charterers appoint a superintendent ensure that the ship retains an original copy of Charterer’s loading instructions. If the Master is in any doubt he should take advice from his owners and express that doubt in a letter of protest.
Ship’s staff should ensure that the cargo is tested for moisture content. The maximum humidity content for rice to be shipped is accepted as 14%, above that figure any problems can be expected at the discharge port. Obtain cargo quality certificates but do not rely upon them. If at some Asian ports where rice is loaded, a government inspector can be physically threatened by cargo interests for attempting to reject wet bags, then cargo interests are capable of producing cargo quality certificates which state what is in their best interests and which may have little relevance to fact. The agent may not be the best person to approach in obtaining such analyses as his allegiance is very likely to be with Charterers. Masters should approach the P&I club local correspondent for such advice, or via his owners, the club directly. It is frequently the case that the load port ship’s agents are appointed by charterers upon the recommendation of shippers.
If the cargo is loaded from barges it is essential that ship’s officers go down into those barges and check the cargo for signs of wetness before each and every barge commences discharge to the ship. Any bags showing signs of being wet or having wet contents should be rejected and if necessary joint samples taken with cargo interests for humidity analysis. Those analyses should not be done at a laboratory customarily used by cargo interests, the laboratory needs to be entirely independent and the local club correspondent will be able to advise which laboratory would be most appropriate for this work.
If rain is likely, instructions should be obtained from the shippers and charterer and weather watchers should be appointed. The Master may also be able to use the radar to predict any forthcoming rain showers. There should be enough crew on board to close the hatches if rain is expected. In certain conditions and ports, hatch tents can also be erected to ensure the maximum possible protection of the cargo during loading.
Rain letters
Some charterers issue a ‘rain letter’, which supposedly provides an indemnity against the consequences of carrying out loading operations in the rain. There are several problems associated with this. Firstly, the cargo being loaded and the cargo already in the cargo space may be directly wetted by rain and suffer damage. Secondly, the rain will raise the moisture levels in the hold, leading to a substantially increased risk of condensation and damage to the cargo.
There is a prospect that if a rain letter is issued and accepted, and cargo damage occurs as a result of loading in rain, P&I club cover could be prejudiced as a result of the Member deliberately carrying out cargo operations in circumstances where they know cargo damage may occur. In that case the owner may have to rely on the rain letter instead of his normal P&I club cover. Where there is evidence that condensation may have caused the problems, some charterers try to argue that any resulting cargo claim is the owners’ fault, arising out of failure to properly ventilate the cargo, forgetting the part they may have played in creating the conditions that led to the condensation.
Hence, the use of rain letters should be avoided.
Pre-loading hold preparations
Hold washing
Prior to vessel’s arrival at the port of loading, the holds should be cleaned of all previous cargo residues and water washed. If possible, the water used should be fresh water only. It is normally the case however, that ship’s staff wash down the holds with sea water and when cleaned, the steelwork is rinsed down with fresh water. The latter should be a thorough operation as it is imperative that all chloride residues are removed after the sea water wash. If not, and if condensation forms during the voyage, and that condensation is present at the discharge port, this is likely to be tested by cargo interest’s surveyor by simple chemical tests to detect the presence of chlorides (silver nitrate). The results are likely to be positive if there are residues of chlorides from the seawater wash and cargo interest’s surveyor will readily, and happily conclude that such evidence proves that seawater ingressed the holds during the voyage. Additionally, the presence of chlorides and moisture create ideal conditions for mould growth.
Ballast tanks
The double bottom ballast tanks and top-side ballast tanks (if any) should be pressed up prior to loading to ascertain watertight integrity.
Bilge suctions and tanktop openings
These should be thoroughly examined, tested and proved fully operational and the strainer plate over-covered with burlap. Bilge wells should be opened and cleaned. Any openings into the tanktop should be examined and proven to be watertight and properly secured.
Sounding pipes and other hold pipes
These should be examined and cleared of any debris. Any pipes within the holds, including ballast pipes or tank air pipes should also be closely examined and ensured that they are in good condition. Ensure that sounding pipe closures on deck are watertight.
Hatch covers
These should be examined and hose or preferably ultrasonically tested and proven satisfactory. The hatch cover test should also extend to the hold access covers and any deficiencies corrected.
Hold ventilation
Ensure that the ventilation shafts and flaps are in sound condition and the flaps operable and capable of weather-tight closure. In the event the vessel has mechanical ventilation ensure that it is services and in good operable condition.
Tightness of hatch covers
Approximately one third of all P&I claims are cargo-related. A significant portion of cargo claims is caused by water damage, of which numerous cases relate to ingress of sea water via the hatch covers of dry cargo vessels. Reports of leaking hatch covers are the most frequent cause for selecting a vessel for an unscheduled condition survey.
In sailing vessels the cargo hatches used to be small, as small as possible, in order to preserve the integrity of the hull. Decks were often awash during ocean passages and the smaller the opening, the smaller the risk of flooding the holds. In the ships of today the cargo is no longer carried on board on the backs of strong men, and the speedy loading and discharge methods require much larger deck openings. Very large openings actually, but manufacturers have been able to design and build strong enough steel covers and closing devices to cope with the demand – strong enough and tight enough at the time of testing and delivery of the new ship, but as the vessel ages, however beautifully, the hatch covers are prone to suffer from wear and tear, and problems of tightness arise.
When leakages occur, ship managers may blame weather conditions rather than possible lack of maintenance of hatch cover tightness systems. One will often find, however, that there is evidence of both: bad weather and poor condition of hatch cover tightness systems.
A carrier’s liability for cargo damage relating to sea water ingress via the hatch covers often depends on whether he can demonstrate that he exercised due diligence to make the vessel seaworthy before and at the beginning of the voyage in question. Whilst this is an onerous burden of proof to meet, a carrier who can show diligent procedures and practices with regard to inspection, testing and maintenance will be less likely to encounter problems from the outset, and will be better placed to show that due diligence has indeed been exercised. Hence, good maintenance and proper testing of hatch covers is a clear loss prevention issue.
In the following paragraphs we look at some major points related to the tightness of cargo hatch covers of dry cargo vessels.
Law and order
The 1966 International Convention on Load Lines contains regulations on the position of hatchways, height of coamings, strength of covers and the need for securing devices. These regulations have to be complied with for the issuance of an International Load Line Certificate. Flag states normally authorise the vessel’s class society to carry out inspections and to issue various certificates on their behalf, including the Load Line Certificate.
In addition, the class societies have rules for the construction of hatch coamings and hatch covers, and these have to be complied with in order to obtain a Classification Certificate covering the vessel’s hull.
Hatch covers are inspected annually, by a class surveyor, for the purposes of the two certificates mentioned above, so class societies have a major influence on the degree of hatch cover maintenance needed as far as certification is concerned. The responsibility for maintaining vessel’s hatch covers and locking devices lies with the owner and operator, but class and flag state are responsible for certifying compliance with classification and load line rules. Also, SOLAS regulations for the issuance of an International Cargo Ship Safety Construction Certificate touch upon the subject, and require openings on deck to have the means to be watertight.
The purpose of the International Safety Management (ISM) Code is to provide standards for the safe management and operation of ships. Its requirements include the creation of procedures for maintenance of the vessel and for inspections and reporting. When checking the text of such procedures, surveyors often see that not much attention is paid to the vessel’s hatch covers. The hatch covers are important to the safety of the vessel, crew and cargo, but are often addressed in very general terms only, or hardly mentioned in the vessel’s maintenance procedures. Members are strongly recommended to include instructions from hatch cover manufacturers in the vessel maintenance program, including records of maintenance, tests and repairs.
Weathertight or watertight ?
The International Load Line Convention contains principles for assigning minimum freeboard to ships: limits to how deep vessels are allowed to be loaded to perform a safe voyage. It also includes regulations on how to construct and equip vessels to avoid ingress of sea water through various openings. It addresses primarily the safety of the vessel, not the safety of the cargo. The convention requires hatch covers to be “weathertight”, which may lead to arguments on how tight the hatch covers really need to be, as the word “watertight” is not used. However, the Load Line Convention itself states that “weathertight” means that in any sea condition water will not penetrate the ship.
Surveys for the issuance and maintenance of the class and statutory certificates do not always seem to be sufficiently strict to ensure that the cargo carried is safe from the ingress of water through the hatch covers. A few tons of water into a cargo hold may not represent a risk to the safety of the ship, but even very small amounts of water may for instance damage a sensitive steel cargo. Class surveyors are not particularly trained to care for the cargo, with the result that cargo hatch covers approved during a load line inspection may fail during a P&I condition survey. Class Societies have had different rules concerning the frequency of hatch covers tests in the past.
According to the International Association of Class Societies (IACS)’s publication Care and survey of hatch covers of dry cargo ships – Guidance to owners, a special survey “shall, as a minimum, consist of checking the effectiveness of sealing arrangement of all hatch covers by hose testing or equivalent as necessary”. But how does a surveyor know if a hose test is necessary? It is certainly necessary to test hatch covers much more often than every five years, for the safety of the cargo, and class societies should encourage surveyors to do that. A recommendation to carry out a hose test of the hatch covers “as necessary” gives surveyors some freedom to omit the test when faced with practical difficulties (e.g., loaded vessel when no ultrasonic testing apparatus is available) and to carry out only a visual inspection.
Hatch cover problems
When hatch covers are leaking, the rubber gaskets are the first to gain attention. Rightly so, because many problems are directly linked to their condition, and the crew may be able to change the gaskets themselves. Regrettably, however, some owners limit hatch cover attention to replacing the gaskets when worn out, and miss out on many of the finer points of hatch cover maintenance. Most hatch covers have movable parts like hinges, hydraulic cylinders, wheels, cleats, toggles, all exposed to wear and tear over time and having an influence on how well the hatch covers work. Also, corrosion and physical wear of fixed parts of hatch coamings, hatch panels, storage racks, etc., may lead to leaking hatch covers. Due to the frequent operation of the covers and the loads and forces they are exposed to, vessel’s hatch covers will age faster than the ship, and will need constant maintenance or major renewals during their lifespan. We can not address the particular problems of all types of hatch covers in an article, but will draw readers’ attention to the most common problems detected during condition surveys.
Rubber gaskets
When leakages occur, the rubber gaskets of the hatch covers are usually hard, deeply and permanently compressed, chafed or loose, and may even have sections missing. Gaskets may be of solid rubber, or have a hollow or sponge core. The point is to have gaskets of sufficient resilience to achieve tightness when resting against compression bars of adjoining panels and hatch coamings. The design compression for common gasket types is usually in the range of 10-15 mm, depending on the thickness, and a manufacturers’ rule of thumb is to replace the packing when a permanent impression reaches half the design value. This may seem a hard rule to live by for many superintendents, but that is how to avoid leaking hatch covers in bad weather. Surveyors often see hatch cover gaskets with permanent depressions around one third of the thickness. Such gaskets should definitely be replaced. When replacing gaskets it is important that the retaining channels be in good condition and maintained against corrosion. It is recommended to use original gaskets and to seek the hatch cover manufacturer’s advice. There are a lot of low quality rubber gaskets on the market. Cheap rubber gaskets will rapidly become permanently compressed and the loss of resilience may cause lack of tightness after a few months of service. When buying original rubber gaskets, the best price is normally obtained directly from the hatch cover manufacturer. Ship managers often leave the job of replacing the gaskets to the crew, with a variety of results. It is certainly cheaper than doing the job in a shipyard, but in all fairness the crew can not always be expected to do as good a job. At least some support from a skilled worker or supervisor is recommended. Pre-shaped corner sections should be glued in first and the straight lengths of gasket thereafter, slightly oversized in length. Surveyors often see gaps at joints of gaskets, as lengths are cut too short. Short pieces of gasket should be avoided, as they often fall out later. When gaskets are chafed or even clipped lengthwise by the compression bar, they must be replaced without delay.
Retaining channels
The gasket retaining channels are among the weakest construction parts of the hatch covers. Their maintenance is cumbersome and often neglected, and retaining channels are often reduced by corrosion and are thus not able to provide sufficient support of the gaskets. When gaskets are replaced, one should always use the opportunity to clean the retaining channels for rust and have them thoroughly coated. Retaining channels may be so reduced by corrosion that as the rust flakes are removed the new packing will fit in too deeply. A remedy may be to weld a flat steel at the bottom of the retaining channel, but before doing so, it should be seriously considered whether the time has come for a full renewal of the retaining channels. Heat applied by welding to a weakened steel channel may cause deformations, making tightness difficult. Retaining channels may also have been damaged by contact of grabs, wires for pulling, etc. Damaged corners are often noted in hatch covers of the single pull type on older vessels. Such damage may be a result of panels slamming against each other or against the hatch coaming top, during closing operations.
Steel to steel contact
One thing is fundamental to a good result when changing gaskets, and that is to check the steel to steel contact between the hatch covers and the hatch coaming top. Good and original gaskets may be rapidly damaged by over- compression if this steel to steel contact is not achieved. Surveyors have met superintendents who are satisfied that the hatch covers float on the gaskets alone, and who even damage the gaskets further by increasing the force of the vertical periphery cleats. The full weight of the hatch covers is not supposed to be borne by the gaskets alone, only to the extent that the correct design compression of the gasket is achieved, and then limited by the hatch cover resting steel to steel on the coaming top. For older vessels the steel to steel contact will often be affected by wear and corrosion of the resting pads, or if these are not fitted, by reduction of the lower edge of the hatch covers and by wear and corrosion of the contact area on the hatch coaming top.
The solution is to fit new resting pads of adjusted thickness to achieve a correct design pressure of the gaskets. If that is necessary, the ship manager should consider whether his crew is qualified for the job, or whether it is necessary to go to a repair yard with specialists or to ask the hatch cover manufacturer for support. Surveyors have seen gaskets being replaced by crew every six months due to the steel to steel contact not being correctly achieved.
Compression bars
The compression bars on hatch cover panels and on hatch coaming tops need to be straight and the top edge must be well rounded and have an even surface. On older vessels they often have heavy scales of corrosion, and when the scales fall off in sections, the compression bars are left with high and low areas where compression of the gaskets will be unequal. Such compression bars should be chipped and maintained by coating. On some ships the compression bar consists of a stainless steel bar, welded to the top of a supporting flat steel. Such compression bar is preferred, as the surface stays always smooth and even.
For ship types with expected large movements between hatch covers and coaming while at sea, manufacturers may have designed gaskets not landing on a compression bar, but directly on the flat top of the coaming. For such type it is important that the landing areas are kept free of rust and debris and well maintained against corrosion.
Guiding of hatch covers
When hatch cover panels are placed in position there are, depending on the type, various means to guide them correctly into place. Wear and distortion of items like stoppers, guide rails, track ways, flanged wheels, etc., may allow the panels excessive sideways and longitudinal play and result in the gaskets landing off centre on the compression bars. Worn bearings and bent wheel shafts will also cause a lack of proper guidance for the hatch covers, with the same result.
Whenever closing of hatch panels includes “attacks” by crew members armed with heavy crowbars and sledge hammers, something is wrong both with the guiding of the hatch covers and with the general maintenance policy on board. If cargo hatches can not easily be closed due to operational problems, there is also the risk of cargo damage by rain water during times of loading and discharge.
Means of securing
There are various ways to secure the hatch covers once they are in place, depending on the type. Modern covers may be self cleating or secured by hydraulically operated cleats or wedges, but the most common type on older vessels is the manual quick-acting cleat, having a cam at the upper end, which is forced onto a snug on the hatch cover panels. A rubber disc between two steel washers at the lower end of the cleat has enough elasticity for the cam to be placed on the snug by using a portable lever. Thus the hatch covers are restrained from lifting, but are allowed some movement on the hatch coaming in the transverse and longitudinal directions.
Surveyors see a lot of poorly maintained cleats in older vessels, and the common problems are that the cleat is seriously weakened by corrosion or that the rubber disc is hardened and without elasticity. Nuts and treads may be so corroded that adjustments can not be carried out. The snugs, which are welded to the hatch cover panels, may be heavily corroded or damaged, offering no strength to the assembly. A well known problem on ships of some age is advanced corrosion around the passage of the cleat through the hatch coaming top plate. When all such areas of the coaming top plate are weakened, one risks losing the covers under extreme weather conditions.
When hatch cover panels are not sufficiently linked together by hinges, they also need cleats across the cross joints of the panels. These may be in the shape of wedges or screw-cleats. Surveyors often find such wedges to be missing, not engaged or not providing any force on the adjoining panel due to wear or distortions. In the worst cases, all the wedges have been removed and are nicely stored within the forecastle. Some covers may have internal cleats on torsion bars, operated manually or automatically. These are meant to save the crew some work, but when old, such arrangements may not provide sufficient pressure on the cross joint gasket due to wear, and water tightness may possibly not be complete. Such securing arrangements are more difficult to inspect than external ones.
Hatch covers may have distortions making it difficult to achieve watertightness of the cross joints by the original cleating system. Some owners may then choose to install additional cleats, like screw-cleats, to solve the problem, but it is then important to check that the additional cleats closing one joint better do not open the next one. It is always recommended to consult the manufacturer.
High stowing type hatch covers, like the folding type, are sometimes left unsecured in raised position. That represents a danger to the crew and stevedores, and the hatch covers themselves may be seriously damaged if they fall. Securing devices are often seen to be damaged and not functional, or are simply not engaged by the crew. Such mechanical safety devices should always be well maintained and engaged.
Gutters and drainpipes
Gaskets in good condition and regular maintenance and tightness tests of the hatch covers are a must to avoid water ingress into the cargo holds, but in the event that some sea water may penetrate the gaskets during heavy weather, it is important that the water does not enter the cargo hold, but drains out again. Cross-over joints between panels will have gutters fitted underneath the packing to catch small amounts of water penetrating.
These gutters will drain the water to the hatch coaming gutters, and it is important to check that they are not fractured or damaged at the ends, so water drains down the inside of the coamings instead. The hatch coaming gutters will drain the water aft to drain pipes. These gutters are not always well maintained and may have layers of corrosion. They should be kept clean and coated in order to ease the flow of water, and all remains of cargo should also be removed before closing down the hatch covers. Often the inner edge of the gutters, being the top of the vertical hatch coaming plate, may have been chafed by wires, hit by grabs or reduced by corrosion. Such damage will allow the water to overflow to the cargo hold instead of being drained to the drain pipes, and should be repaired and always kept in good condition.
The drain pipes aft are often of small diameter, and are easily clogged up. The pipes need to be fitted with a non-return device, in order to avoid that green sea on deck finds its way into the cargo hold through the drains. Non-return valves easily clog up, so that they must either be frequently opened up for cleaning, or it may be better to fit a three-foot canvas hose to the drain pipe instead. The canvas hose must be of a pliable type and be well secured by hose clamps of stainless steel.
Temporary repairs
In older vessels there are often signs of rather desperate efforts to keep hatch covers tight by external taping, and by applying foams and fillers at joints between panels, etc. Rubber liners have been seen glued on top of hardened and worn out gaskets, and tape glued on top of compression bars to build them up to improve compression. On one vessel the crew had run out of tape and tried to improve the watertightness of the cargo hatches by installing a rope covered with cement around the perimeter of the covers. Surveyors have also seen vessels with hatch covers in poor condition being fitted with tarpaulins, pulled down at sides by ropes fixed to any pipe or fittings on deck. Such remedies are often requested by cargo owners or charterers to reduce the risk of water ingress.
The master of the vessel may choose such means, if he has doubts about the tightness of the vessel’s gaskets and has a sensitive cargo to carry. All such means are, however, only considered to be temporary repairs, and should not be allowed to replace a fully functional original tightness system. The effects of such remedies are also very limited if heavy weather is encountered. The bonding of the tape is not stronger than allowed by the surface condition of the hatch covers and any firm tightness around cleats, etc., is difficult to achieve. Tape may lose elasticity in cold weather and be ripped off by seas on deck. Tarpaulins will help against sea spray, but will be ripped off if all edges are not firmly wedged in against the coaming. The money spent on expensive tape and fillers could be better used if spent on regular maintenance of the hatch covers and on well planned renewals of the original gaskets.
Tightness tests
There are mainly three different ways to test hatch cover tightness, and they all have some pros and cons. The chalk test is often carried out when the vessel is new, in the shipyard. All compression bars are rubbed with a piece of chalk, thereafter the hatch covers are put in place and secured, and then opened again. If there has been insufficient compression between the compression bar and the hatch cover gasket, there will be a lack of or incomplete chalk marks on such areas of the gasket. The advantage of this test method is that one can see exactly where the problem is. Also, it is clearly seen from the chalk marks if the gasket lands off-centre on the compression bar. The disadvantage is that one needs quite a bit of chalk, which is normally not found on board. The method is rather time-consuming, and it can only be used in dry weather.
The hose test is the traditional way of testing hatch covers. It is easy to carry out, and the crew can do the job. It is inexpensive, as a fire hose with a nozzle and good water pressure from the fire pump is all that is needed. It is recommended to perform the hose test regularly between cargoes, to prove hatch covers are in good order. It can be useful to have good results of hatch cover tests entered in the log book. Some of the disadvantages of the hose test are that it sometimes becomes just a lot of messing around with water and it is not recommended to be carried out on loaded vessels – more than once the hose test itself has caused water damage to cargo. Good water pressure is needed, but not always produced, and of course the test can not be used if temperatures fall below zero.
From a surveyor’s point of view, the hose test also has the disadvantage of not being fool-proof: the surveyor will not be able to observe how the spraying is performed on the outside, while he is inside the cargo hold looking for leakages. If a hard water jet is not aimed directly at the hatch cover joints, the test may be worthless. The condition of the hose test can be improved by fitting rags at the outlets from the cross over joints, to contain the water in the spaces between the panels. Another useful trick is to fit plastic bags to the drain pipes from the hatch coaming gutters. If water has ended up in the bags following the hose test, it has passed the gaskets and drained by the gutters to the outlets. Using this method, a surveyor reduces his chances of being fooled by the crew if he chooses to observe the testing from inside the hold.
The latest and most accurate way of testing hatch covers is by using an ultrasonic apparatus. A unit emitting ultrasound is placed inside the cargo hold and the operator registers “leakages” of ultrasound through the hatch covers using a handled detector. Normally one will first measure “open hatch” values and establish 10 per cent of such as the lower acceptable limit with hatch covers closed down. The ultrasonic test method is easily carried out by a hired operator, and the location and importance of leakages are clearly identified in his report. The method has the great advantage that it can also be used on loaded vessels, by placing the transmitter on top of the cargo. Another advantage is that it can be used in cold weather.
Major steel exporters may require satisfactory ultrasonic tests carried out on all ships, to reduce risk of damage to cargo. A satisfactory ultrasonic test, correctly documented by the professional operator, will carry some weight if a dispute about hatch cover condition should arise. Nowadays ultrasonic test equipment is available in all major ports, operated either by specialist firms, or by traditional marine surveyors. The only disadvantage with this method is probably that it is not always much liked by all ship managers, as “too many leakages” are detected. There is some truth in that, and the operator and his principals need to exercise some care in judging the results, as even quite small, insignificant “leaks” may be detected. Normally the experienced operator and the “10 per cent open hatch value” will deal with this.
Conclusion
Regardless of method it is recommended to test the vessels’ hatch covers regularly, to watch out for indications of deterioration, and to initiate maintenance early on, ensuring cargo is carried under safe conditions. Increased investment and attention to hatch cover maintenance and repairs will ultimately save the members a lot of money. It is, simply put, good loss prevention.
Dunnaging
Dunnage usually consists of bamboo sticks laid in a criss-cross fashion on the steel tank tops. These are overlaid with kraft paper sheets and/or bamboo mats. This is similarly laid along the sides of the vessel’s bulkheads and side shell. The problem with bamboo sticks are that they are not free from moisture and retain and bleed moisture into the cargo holds while the ship is in transit. Bamboo sticks may appear dry on the outside but may have a moist pulpy interior.
Though the use of bamboo sticks/matting and kraft paper are seen as the customary dunnaging materials used in loading bagged rice. Nowadays charterers insist on a combination of sheeted styrofoam, polyethene sheets and kraft paper.
While there is no scientific evidence available it would appear this type of dunnage better protects the cargo from variations in temperatures, insulating the cargo from ship’s sweat. One still needs to ventilate!
Ventilation channels
Ventilation channels within adjacent block stows should be arranged in a manner consistent with the direction of ventilation air flow within the holds. Individual stows should be ‘tied’ together with transversely arranged bags usually at each fifth tier spanning the ventilation channel. It is usually the case that ‘natural’ i.e. non mechanical, ventilation is arranged such that the air flow is fore-and-aft. To ensure proper air circulation, bags should be stowed leaving ventilation channels of 10-15 cm at horizontal intervals of about 20 bags, with individual bags blocking the channels at intervals of 5-6 tiers to ensure vertical strength and stability.
In addition to the above, it is recommended that cargo is placed within the corrugated bulkheads. In this way, the problem of bags falling from the top and bursting, resulting in cargo shortages at the first ports, is also eliminated.
Condensation
Introduction
Sweat is the term commonly used to describe condensation that forms in a vessel’s cargo spaces. This formation of moisture can cause damage to and/or deterioration of the cargo. The vessel has a very important role to play in avoiding this damage. Sweat can result from the vessel’s improper ventilation of the cargo space, or lack thereof, and damage can be minimised or even avoided by proper cargo stowage arrangements. Experience is that a claimant will invariably allege a failure of the vessel to follow proper ventilation practice or to properly stow the cargo. Under the Hague/Hague-Visby Rules this would be an alleged breach of Article III Rule 2.2.
Unfortunately, in too many cases, the carrier is unable to sustain a defence to these allegations, not only because evidence suggests that the vessel has been at fault, but also because the vessel does not have sufficient evidence (e.g., proper ventilation records).
Types of sweat and how they form
The two main types are cargo sweat and ship’s sweat. In this respect it is important to understand what is meant by “dew point”. All air contains water vapour of varying quantities. The dew point indicates the amount of moisture in the air. The higher the dew point, the higher the moisture content of the air at a given temperature. Conversely, the dew point of humid air will be higher than the dew point of dry air. Dew point temperature is defined as the temperature to which the air would have to cool (at constant pressure and constant water vapour content) in order to reach saturation. A state of saturation exists when the air is holding the maximum amount of water vapour possible at the existing temperature and pressure. Condensation of water vapour begins when the temperature of air is lowered to its dew point and beyond.
Cargo sweat
Cargo sweat is condensation which forms on the cargo. It occurs when the temperature of the cargo is less than the dew point of the air in the hold. The cargo cools the air in contact with it and condensation forms on the cargo. The cargo may therefore be damaged by direct contact with moisture. Cargo sweat is most associated with the incorrect ventilation of warm moist air into a hold with cold cargo. It is akin to the condensation forming on a cold drinks can when taking it out of the fridge on a summer’s day.
Ship's sweat
Ship’s sweat is condensation which forms on the internal ship’s steelwork. It occurs when the temperature of the ship’s steelwork is lower than the dew point of the air in the hold. Condensation will form on the deckhead and/or on the inside of the shell plating. This moisture can then drop down from the deckhead on to the surface of the stow or come into contact with the cargo stowed directly against the sides of the hold. Ship’s sweat is most associated with a voyage to a colder climate and the failure to ventilate the hold, replacing moist air from the load port or air made moist by the cargo, with drier air. It is akin to the condensation forming on the window when taking a warm shower on a cold winter’s day.
Proper ventilation practice to avoid sweat
The decision to ventilate and, equally important, when not to ventilate, so as to avoid sweat, should largely be based on the following considerations:
The nature of the cargo and its packing – There are two basic groups of cargo, which pose significantly different risks of sweat: hygroscopic and non-hygroscopic.
Hygroscopic cargoes
Hygroscopic cargoes contain moisture, mostly in natural form; for instance, agricultural, fish and forest cargoes. For example rice has a moisture content of around 14%. It is important to note that these cargoes can absorb and release moisture. It is more likely that damage is caused when moisture is absorbed. A hygroscopic cargo with a moisture content and temperature such that water vapour will leave the cargo and enter the hold air will result in the build up of moist air and increase the risk of sweat.
Non-hygroscopic cargoes
Non-hygroscopic cargoes contain no moisture; for example, steel. Whilst non-hygroscopic cargoes may be wet before shipment, e.g., because they have been affected by rain before loading, it is better to avoid shipment of wet cargo rather than face the difficult task of deciding whether or not to ventilate. Non-hygroscopic cargoes do not give off moisture, but may absorb or be damaged by it.
Packing
Packing is an important factor and, for the purposes of ventilation, it can essentially make a non-hygroscopic cargo a hygroscopic cargo and vice-versa. For example, wood is hygroscopic and is often used as packing. Again however, the emphasis should be on avoiding shipment of wetted cargo.
Climatic changes on the voyage
Consideration needs to be given to the temperature and humidity conditions expected from the place of loading through the voyage to the place of discharge, as is relevant to the time of year. The term climate includes here the sea temperature, as that has particular relevance insofar as ship’s sweat is concerned. The sea temperature will have the greatest effect on the temperature of the steelwork in the hold which is adjacent to or in contact with the sea.
Putting together all of these factors, the risk of sweat can be predicted and therefore, broadly speaking, it can be decided whether ventilation is necessary, unnecessary or to be prevented.
Some examples
Hygroscopic cargo from warm to cold climate – There is a danger of heavy ship’s sweat and vigorous ventilation will therefore be necessary to replace moist air with drier air. The air in the hold may already be moist from ambient air at the place of loading, but is also likely to receive large volumes of moisture from the cargo itself.
The aim is to lower the dew point temperature, thus making it unlikely that the steel structure of the vessel can cool air in contact with it sufficiently to reach that temperature.
Hygroscopic cargo from cold to warm climate – The risk of sweat is generally low and ventilation is therefore largely unnecessary. There is a risk of cargo sweat if warm moist air is introduced into the hold.
Non-hygroscopic cargo from warm to cold climate – There may be a risk of ship’s sweat if the hold air is moist from the load port. Ventilation to improve the dew point of the hold air is therefore advantageous.
Non-hygroscopic cargo from cold to warm climate – Cargo sweat is likely if warm moist air is introduced into the hold. Ventilation is not therefore necessary and the holds should be sealed.
As an aide mémoire, mariners have often relied on the following very general rule:
“Warm to cold: ventilate hold
Cold to hot: ventilate not”
It is important to remember, however, that the vessel will often pass through different climatic regions. In the example given for ship’s sweat above, whilst ventilation was necessary in the first part of the voyage, it was not necessary in the second part from the Cape of Good Hope to West Africa. It may also be very dangerous to ventilate, as has been shown in the example given above for cargo sweat. In that case the vessel ventilated whilst transiting humid conditions in the Red Sea, with the result that moister air was introduced into the holds. With all this in mind, a rule is required to ensure that, when the vessel does ventilate, it improves the air conditions in the hold, and thereby reduces the risk of sweat developing.
The Dew Point Rule
The Dew Point Rule is probably the most common rule followed to ensure best ventilation practice. It is simply:
- Do not ventilate if the dew point of the ambient air is higher than the dew point of the air inside the cargo space.
- Ventilate only if the dew point of the ambient air is lower than or equal to the dew point of air inside the cargo space.
- Remember, a higher dew point is bad and a lower dew point is good.
- Clearly, when it is raining, snowing, etc., or it is foggy, misty, etc., it will not be safe to ventilate.
The sea conditions
If, in adverse sea conditions, there is a risk of sea spray entering the ventilation openings to the cargo spaces, no ventilation should take place and the ventilator openings should be closed and sealed.
Inspections of the cargo spaces
The cargo spaces should be inspected regularly to check for signs of sweat (providing it is safe to enter).
Hours of darkness
Providing ventilation can and should be carried out, based on the above considerations, ventilation should continue to take place night and day. A failure to ventilate at night will probably be viewed unfavourably by a court or arbitration tribunal, unless
of course there was a valid reason not to ventilate.
Shippers’ instructions
Shippers may have special instructions for ventilation. If these are at odds with what the vessel would expect, it would be prudent to obtain the views of an expert.
Expert advice
If there is any doubt about ventilation, expert advice ought to be sought.
Ventilation systems
Vessels are normally fitted with one of two systems: natural or mechanical.
Natural ventilation simply describes a system whereby ambient air is allowed to enter and leave the hold naturally, via trunking connecting the hold to and above deck level.
Mechanical ventilation describes a system whereby air movement is forced, usually by electrical fans that are fitted in the ventilation trunking. These can usually be operated so as to either draw air into or eject air out of the hold.
System features
In the hold there is usually two or more ventilation openings in the deckhead, one set forward, one set aft. This arrangement therefore only provides for surface ventilation of the cargo. It is less common for the trunking to extend down the bulkheads, so as to provide through ventilation (not normally required for bulk cargoes). Above deck the trunking may stand alone or may be built into part of a deck structure, e.g., the hatch coaming. Whatever the system, every ventilator should be provided with a means of closing, e.g., a screw-down mushroom cover, a flap or door. If the on-deck trunking is on a swivel arrangement, the vent opening can be turned to face forward when safe to ventilate (so as to maximise air intake), or aft when there is a risk of sea spray. The trunking arrangement may serve holds on an individual or common basis. Where cargoes with different ventilation requirements are stowed in different holds, care will need to be taken to arrange stowage and ventilators correctly.
Ventilation in practice
With natural ventilation, the air will usually move from forward to aft, with the movement of the vessel. Mechanical ventilation can aid this movement by setting fans to draw in forward and eject aft. It is important to avoid short-circuiting the air movement, e.g., via a hold opening between the ventilators. Fans can usually be operated at various speeds, so for example when vigorous ventilation is necessary high speeds can be used. If, despite ventilation, ship’s sweat is still occurring, the hatch covers can always be opened. Opening the hatch covers may also be necessary where there is an air pocket in the hatch square, caused for example by a high cargo stow.
System checks
Some points to check with ventilation systems:
- Closing appliances are often exposed on deck and easily become rusty. They need to be kept in good condition so that they can be opened and closed with ease. The ventilators will often need to be operated numerous times during the voyage, and often at short notice, e.g., sudden heavy sea spray. Surveyors for cargo interests often suggest that the vessel can not have ventilated properly when they find ventilators in poor condition and difficult to operate.
- The closing mechanism should always be checked to ensure an effective seal.
- Ventilators should be clearly marked to show when they are in the open or closed position (unless obvious), and also show which hold they serve.
- Fans for mechanical ventilation should be checked for operation before loading.
De-humidifiers
On some ships fixed or portable de-humidifying units may be fitted in the holds. These act to remove moisture from the hold air and therefore control the dew point.
Charterparty
The ventilation system should be properly described in the charterparty and care should be taken to avoid accepting ventilation requirements, which may be difficult or even impossible to comply with. It is also a good idea to obtain written acknowledgment from the shipper where the vessel is only fitted with natural ventilation, particularly on voyages where ship’s sweat is expected. The shippers are then on notice of the vessel’s ventilation limitations.
Temperature measurements and ventilation records
Determining the dew point
Compliance with the Dew Point Rule requires determination of the dew point. If cargoes requiring ventilation are to be carried it is very important that the vessel has on board the necessary instruments, with spares, to determine the dew points, and that the crew is properly trained to use the instruments. If the vessel is not properly equipped it risks being uncargoworthy and in breach of Article III Rule 1 (b) of the Hague/Hague-Visby Rules. Most vessels have a basic psychrometer on each bridge wing housed within a Stephenson screen. The psychrometer consists of two thermometers which are identical, save for one which has its bulb covered with a jacket of tight muslin cloth, and which must be saturated with distilled water.
The dew point is determined from careful reading of the temperature on the two thermometers and by reference to dedicated dew point tables, such as those found in the Mariner’s Handbook. Using the psychrometer on the windward bridge wing will give the dew point of the ambient air. For the holds, a psychrometer can also be used, preferably within the hold (providing it is safe to enter). Temperatures should be taken at various places and sufficient time needs to be allowed for thermometers to acclimatise (the psychrometer should be waved in the air). If the holds can not be entered, the psychrometer may be placed down the outlet ventilation trunk or hold access.
Records
As mentioned in the introduction, records are essential to the carrier’s defence of cargo claims. It may be that, on some voyages, sweat can not be prevented. For example, ship’s sweat resulting from ventilation being restricted due to say fog or heavy seas on deck. In those circumstances it may be necessary to evidence that the vessel did ventilate as much as it reasonably could, when it could. On the other hand, moisture damage to the cargo may be due to the inherent nature of the cargo itself, e.g., pre-shipment moisture content, and the carrier may need to evidence that when the cargo was ventilated it was ventilated correctly. It is important to bear in mind that, even if poor ventilation practice has only contributed to cargo damage, with the predominant cause being, for example, inherent vice of the cargo, the carrier faces the difficult, if not impossible, task of having to prove the extent of damage caused by the vessel’s wrong doing so as to avoid liability in full.
It is strongly recommended that a separate ventilation log be drawn up where the observations for each hold are recorded. A suggested proforma is set out below.
In addition to the ventilation record, it is also important to take and record the bilge soundings, as these too will be evidence of moisture within the hold. Obviously, the bilges should be dry before loading.
Stowage
As the reader will have gathered by now, stowage is an important issue, not just in terms of avoiding sweat but also in terms of trying to prevent it from damaging the cargo.
Increasing the risk of sweat
Improper stowage can increase the risk of sweat. For example, stowage of a wet cargo in the same hold as dry cargo. Careful stowage planning is therefore important, but so too is the inspection of cargo before and during loading. A normally dry cargo may be wetted ashore, e.g., due to rain or snow, and it is therefore important to stop such cargoes from being loaded, either to be replaced or satisfactorily dried. Materials used in the stow, e.g., dunnage and shoring, should also be dry.
Moisture migration
Moisture migration, which is the movement of moisture within the cargo stow, is also worthy of mention. For example, moisture will migrate within a bulk cargo of grain to the outer parts of stow when these parts are cooled, e.g., because the ship’s steelwork is cooled by falling air and sea temperatures. The physics at work in this phenomenon are beyond the scope of this article, and it is considered sufficient to appreciate the importance of good stowage to remove excess moisture at the extremities of the stow.
Aiding ventilation
Stowage can go a long way to aid ventilation so as to avoid sweat. A very good example is when ventilation channels are employed in the stow. These can be very effective in preventing ship’s sweat where hygroscopic cargoes are carried from warm to cold climate. Ventilation is necessary to replace air in the hold made moist by the cargo, with drier air from outside. For this reason, stowage channels are often employed with bagged rice cargoes, but the effectiveness of these channels very much depends on the actual arrangement. Some arrangements are better than others and expert advice should be sought.
Protecting the cargo from sweat/moisture
As already discussed, some sweat (notably ship’s sweat) may be unavoidable, particularly at the sides and bottom of the hold where ventilating air can not reach or reach in sufficient quantity. Whilst this is not relevant for bulk cargoes, it is highly relevant for bagged and other packaged/unitised cargoes. In terms of trying to prevent cargo being damaged by sweat, dunnage is key. As already mentioned, it is important that the dunnage is dry, otherwise it defeats one of the very objects for which it is used. Probably the most common dunnage is kraft paper, but this has its limitations. For example, it provides only a thin barrier between the cargo and any moisture and can also easily be torn. A good example is when paper is used to cover the sides of a hold with internal frames (or a hold with corrugated bulkheads).
The weight of the cargo often pushes through the paper spanning the frames, with the result that cargo comes into direct contact with the side of the hold between the frames. This also adversely affects the productiveness of the ventilation channels provided between the frames. In view of these problems it is recommended that kraft paper be used with other (sturdier) dunnage material or cargo battens.
Bamboo sticks and mats have commonly been used for shipments of bagged rice from places such as Thailand and Vietnam. The experience of some operators is that this material is less effective than kraft paper, used with, for example, plastic. This may be because the bamboo already contains some moisture and/or because, compared to paper, it more readily gives off moisture that is absorbed from sweat. It may also be that bamboo provides less of a barrier to cold air contacting the extremities of the stow, and which can be relevant to moisture migration.
On the tank top, dunnage should be aligned so that moisture can flow easily to the bilges. The dunnage should also be strong enough to withstand compression forces.
Charterparty terms
It is fair to say that, in today’s world, shippers generally make it more difficult for the ship in terms of preventing damage caused by sweat. The cheaper stowage option is often chosen and from time to time cargoes with excessive moisture contents are hipped. Owners should therefore be alive to the risks of sweat when arranging fixtures and try to ensure that the charterers are made responsible for stowage. As already mentioned, onerous ventilation requirements should also be avoided.
Conclusion
Shipowners and carriers need to be fully aware of the risks of sweat, which are no less today than they were many years ago. The risks and the control measures need to be understood, not just by those on board, but also by those fixing the vessel’s employment, and by those arranging stowage on the vessel. If proper precautions are not taken and/or proper ventilation practice is not adhered to, either to reduce the risk of sweat and/or protect the cargo from damage by sweat, claims for damage can be considerable. Whilst it can be most frustrating when damage of this nature occurs through a lack of basic seamanship, there is equally nothing more frustrating than when good grounds for defending claims can not be sustained through a failure of the vessel to properly record its ventilation practice. The message is simple – don’t work up a sweat – work out what is needed to control it!
Photographs
Take general photographs of all stows within the holds as the cargo compartments are progressively loaded. These should also show the dunnaging and the ventilation channels. All photographs should be captioned with date, time and location (i.e., which hold and where within that hold). As most ships now have computer systems, deck officers taking these photographs should be instructed to establish a computer record of all such photographs and captions and this record must be committed to computer record daily. The intention is to have a good photographic record of the loading in each hold upon completion. It is adequate for evidential purposes for these photographs to be of 5 mega-pixel quality and each should be reduced in memory size to about 50Kb. This enables them to be transmitted relatively easily by electronic mail. In an ideal world, and from the point of view of the P&I surveyor at the discharge port, if a copy of the completed photographic record is given to the agent (or better the club correspondent) on a computer memory stick for transmission to owners when the ship has sailed, then this can easily be sent electronically to the P&I surveyor who is to attend the vessel in West Africa before he gets there and also to the P&I club claims handler when problems first arise at the discharge port.
Infestation and fumigation
All rice cargoes are fumigated after loading is completed. The fumigation instructions need to be fully understood by ship’s staff and the ventilation system needs to be able to accommodate the fumigation requirements.
The most commonly used fumigants release the fumigant gas as a result of contact between the active agent in the fumigant and moisture in the atmosphere. The resulting vaporization generates heat.
Fumigation brings its own sets of challenges , as that which kills insects will just as easily kill humans. The fumigation process therefore starts with (yet another) survey of the ship prior to loading, usually by an independent surveyor employed by the fumigator. The surveyor will inspect the cargo holds looking to conditions that will allow a fumigant to penetrate into spaces that will be inhabited by crew members. He will look for trunks, piping, alleyways or other communication methods where the fumigant can migrate to areas where it is unwanted. This is especially important at the bulkheads between the accommodation spaces or machinery spaces and cargo holds. If any is found, the surveyor will recommend that it is properly and effectively sealed off. Also checked are the seals on the hatch covers and access trunkways will be marked with warning signs and sealed after the fumigant is applied.
There are many factors to be considered when fumigating a ship, including hold configuration, cargo density, effectiveness of sealing arrangements and toxicity of the selected fumigant. For a charterer, sometimes fumigation is an afterthought and an expense, and is usually applied because it is required in the sales contract due to import requirements in the country of destination. There is a temptation for the shipper to ask a fumigator for a ‘certificate’ at a cheaper than market price and some companies perform only cursory fumigations in order to issue the required certificate. Sometimes the shipper does not want to pay for the expense of applying the proper dose of fumigant.
The most common fumigant used is phostoxin (aluminium phosphide), which requires a reactant in order to begin to work. There has to be sufficient moisture present to initiate a reaction of the product and the temperature of the grain must be greater than 7°C. Tablets of phostoxin are often placed in sleeves that are laid across the surface of the cargo. The sleeves place all of the phostoxin in a sock-like tube so that the residual ash after the phosphine is produced can be easily removed at the discharge port.
If these sleeves are not properly applied, the end result can be that all of the phostoxin does not react, leaving toxins on the top of the stow at the discharge port. If the phostoxin does not all react, then sufficient amounts of phosphine gas are not produced, thus a sufficient dose is not applied. One version of this is the pre-pack rope, which spreads the tablets out in a rope-like container across the top of the stow. The difference here is that the phostoxin tablets surface area has greater exposure to necessary moisture (reactant) in stow, thus better reactivity. This is better than the sleeves, but more expensive. The phosphine sinks slowly. If a hold is not sealed well, air flow within the hold can keep it from sinking and weaken the effectiveness of the dose.
The recommended minimum dosage of photoxin is 33 grams per 1.000 ft3 of space (g/1000). An effective dose is normally 45 g/1000.
In some instances, owners and/or P&I Clubs have hired independent surveyors to witness the fumigation process.
A particular claim may be recalled on a vessel with an Asian rice cargo, where the cargo in one hold had been on fire. This was in the hold forward of the engine room bulkhead which immediately raised the speculation that heat transmission from the engine room may have been contributory. In fact empty rice bags only had combusted. In this hold a few thousand empty polypropylene bags had been loaded on top of the cargo after cargo loading in that hold had been completed. This is customary in the trade and allows for the rice from spilt or broken bags to be repackaged during discharge in order for them to be considered acceptable by receivers. In the event it was possible to show that those empty bags must have been markedly wet when loaded. This argument sustained as the chemical reaction in vaporizing the fumigant is rapidly accelerated by wetness and similarly the heat generated by that chemical process is markedly increased and sufficiently so in this case to ignite the empty rice bags. The conclusion here was that the person doing the fumigation triggered the solid fumigant capsules and threw them onto the cargo from the hold access hatch, the hatch covers having of course being previously sealed. One or more of the capsules must have landed on top of the empty bags which were wet. As the cargo hold fire/smoke detection systems had been isolated as a necessary and essential precaution prior to the fumigation, ship’s staff were unaware that there had been a fire in this hold for some days after departure. Therefore make sure that the empty bags are loaded in a clean and dry condition.
Another type of fumigant is methyl bromide. As a fumigant this product is on the verge of being banned worldwide because it is not friendly to the ozone layer. The real reason it should be banned is that, unlike phostoxin, which is produced with a warning agent, methyl bromide is colourless and odourless and can easily kill humans if not applied properly on a well-found ship. When it is used, the ship should really be evacuated for the duration, thus it is not a good choice for in-transit fumigation. The thing some fumigators love about it is that it is a very quick kill – 48 hours.
The Maritime Safety Committee (MSC) of the Inter-Governmental Maritime Consultative Organization (IMCO) has approved recommendations on the safe use of pesticides in ships.
Insects and rodents on ships are objectionable for various reasons. In addition to aesthetic and nuisance aspects, pests may damage equipment and spread disease and infection, contaminate food in galleys and food stores and cause damage to cargoes that will result in commercial or other losses. Very few pesticides are suitable for use against all kinds of pests that may occur aboard or in different parts of ships.
Insects in cargo spaces and cargoes
Insects and mite pests of plant and animal products may be carried into the cargo spaces with goods (introduced infestation); they may move from one kind of product to another (cross infestation) and may remain to attack subsequent cargoes (residual infestation). Their control may be required to comply with phytosanitary requirements to prevent the spread of pests and for commercial reasons to prevent infestation and contamination of, or damage to cargoes of human and animal food (including both raw and processed materials). In severe cases of infestation of bulk cargoes such as cereals, excessive heating may occur.
Rodents
Rodents should be controlled not only because of the damage they may do to cargo or the ship’s equipment, but also, as required by the International Health Regulations, to prevent the spread of disease.
Be prepared
- If the vessel is to be fumigated in transit, be ready to seal off certain areas or be prepared to move crew members from areas that the surveyor considers may be subject to fumigant migration. Areas of rust scale on bulkheads or piping areas are treated as suspect so remove same before inspection.
- Condition of seals of hatch covers is very important. Keep the phostoxin inside the cargo holds for highest effectiveness. If in doubt, apply Ram-Nek tape or other sealant around the perimeter and across pontoon cross-joints. Remember the fumigant is a gas and treat it as such.
- Make sure cargo hold ventilators can be completely closed.
- Check the dosage of Phostoxin in order to make an effective ‘kill’.
Overseas carriage of rice
Much has been written on the carriage of bagged cargoes to West African ports, in particular, on the carriage of rice. Because the routine problems associated with these cargoes are often exacerbated by jurisdictional problems with the local courts and by underwriters ignoring specific jurisdiction clauses incorporated into the contract of carriage, shipowners may be treated less favourably in respect of any defence that they might otherwise have had available. It is, therefore, essential that precautionary measures are observed, the most important of which are rehearsed here.
Background
The staple diet in many African countries is a maize-based dish sometimes known as "Fufu" or 'Nshima'. However, rice consumption is increasing replacing traditional food sources although rice is not easily cultivated in West Africa. As a result, substantial quantities are imported.
The problems associated with carriage to and discharge of rice in West African ports are well known but, and with a view to loss prevention, nonetheless worth reviewing.
The loading port
Problems at the ports of loading are comparatively rare. This is so even where bagged cargoes are subject to multiple handlings and the cargo has been brought to anchorage by lighter vessels. There are, though, a number of pre-loading checks that a prudent carrier can perform to comply with the carrier's obligation to care for the cargo properly during the voyage. For example, that the vessel's holds are clean and free of salt residues, that the bilge wells and sounding pipes are clear, that hatch covers have watertight integrity, and that ventilation shafts are not obstructed and flaps are operational.
In addition, independent tallying of the cargo during loading is recommended and moisture levels of the cargo checked. Indeed, if average moisture levels are close to or above the moisture level (usually 14%) set out in the cargo quality certificate this is a reasonable indication of a future problem unless steps are taken to investigate the cause and/or replace cargo prior to loading. In this respect reliance on the charterers alone to arrange load tallies and the pre-loading/loss prevention surveys (which include moisture content) may not be sufficient to protect the owner's interests, particularly if the charterers merely instruct their agents to appoint a surveyor. It is frequently the case that the agents are instructed by the charterers on the recommendation of the cargo shipper.
It is prudent to appoint surveyors to randomly sample bagged cargo and have the samples sent ashore for analysis. While hand held moisture readings are taken as past of any survey, the readings are only accurate to within 0,5%. So, if a hand held reading indicates a sample to be 14%, it may actually be 14,5% and in excess of local government standards and likely contractual requirements.
The nature of the stowage of the cargo on board the vessel is also key. Ventilation channels linked to the vessel's ventilation shafts should be constructed. Dunnaging should be clean and dry. In this respect the benefit and advantage has been reported of using dry styro foam sheets, kraft paper and plastic sheets instead of bamboo mats and sticks to combat the risk of condensation damage to the cargo in the holds caused by the changing sea water temperatures during the voyage. Ventilating the cargo by opening the vessel's hatches during the voyage when weather and sea conditions permit have also been reported beneficial.
The loaded passage
The cargo must be ventilated whenever it is possible to do so and in accordance with accepted industry guidelines. Maintain a ventilation record along with a record of weather conditions including wet and dry bulb temperatures (dew point) of external air and air with each individual hold. Observe and record sea water temperatures.
The cargo hold bilges should be sounded twice daily and a record maintained and any unexpected findings investigated and acted upon with appropriate records maintains. Record any hold bilge pumping operations, dated and times etc.
Prior to arrival at the discharge port, the Master is recommended to confirm from Owners that an independent tally firm are appointed at the discharge port on behalf of and paid for by Owners. It is unadvisable to rely upon the tally clerks appointed by Charterers and/or receivers as their commercial interests are at odds with that of Owners.
The discharge port
It is customary for tally clerks in West Africa to describe themselves as surveyors and it is usual for three of tally clerk/surveyors to attend, one each representing either Owners, Charterers’ and Cargo Interests. These surveyors should bring with them original formal letters of appointment without which the surveyor should be asked to leave the vessel and return when one such has been obtained. Record the names of these surveyors, their company detail and which party in the venture they represent.
The surveyors will want to jointly conduct what is termed an ‘opening survey’, meaning when the holds are first opened. A ship officer should be present during this survey and observe and agree whatever is found. If the surface of the stows reveal clean dry bags with no evidence of ingress of water in way of the hatch covers, the Master should confirm this in writing and assuming that all surveyors agree then they should be encouraged to sign that latter of statement. Whatever is seen during that opening survey should be photographed by the vessel and those captioned photographs recorded to computer for later reference. Any apparently wet damaged bags in the upper tier of the stows and the conditions of adjacent bags, and their position relative to the hatch coamings should be recorded and photographed. The wet damaged bags should be set aside for joint sampling and the Master should inform his Owners/Managers immediately. If a group of adjacent bags are found to be wet damaged then the location and size (measurements) of that group should be recorded.
It is not unusual that the three different firms of tally clerks will produce three different outturn reports each day. On these outturn reports they will number clean, torn, wet damaged, cut, stained and caked bags discharged during that day or shift. These reports are almost always in conflict and the Master is recommended to sign these ‘for receipt only’. If possible and dependent upon crew numbers, a crew member should be posted to each cargo hold and tally with the Owner’s appointed tally clerk. If there is no tally being conducted by the ship’s staff or on behalf of the ship (solely) then receivers can be expected to take advantage of this and claim for a shortage.
It is usual, and good practice, for the Ship’s tally and Charterers’ tally to be conducted from onboard the ship and the receivers tally done on the adjacent quay. For this reason, difference in the tallies are inevitable and it is usually impossible to get all three tally firms to agree figures for each day or shift.
As noted earlier herein, these tally clerks can be expected to tally the number of slings offloaded and assume that the standard number of bags is uplifted in each because this is easier than counting each bag. A close watch of the tally clerks by ship’s officers will quickly reveal if this practice is ongoing and if so, this should be supported by a letter of protest from the Master.
Receivers’ tally clerks may conduct their tally at a receiving warehouse some distance from the discharging vessel. In this circumstance the Master must strongly protest that receivers are not tallying the cargo on the quay and therefore they are not counting the bags discharged from the ship. This practice also encourages the sale and/or theft of cargo after discharge from the ship and before receipt at the warehouse.
Corruption and theft
Petty theft by stevedores can be expected at every West African port. Stevedores will take blades into the hold and deliberately cut the bags open and use various means to secrete small packages of rice under their clothing. Violent outburst between ship’s staff and stevedores have been experienced when the former are trying to search the latter by the gangway at the end of a shift. The extent to which such personal searches are made is a matter for ship’s staff to determine, however, photographic evidence of theft can and should be obtained by ship’s staff, but this must be done discretely. In many West African states and on numerous occasions the author has been threatened by customs or immigration or cargo interests with various sanctions and ‘ordered’ not to take photographs when such a restriction was without authority. The response, of course, has been politely agree, but to continue discretely take photographs, and in these situations the very discrete and disguised photography equipment available to purchase today can be very useful.
Organised theft
It has been experienced at one West African port where the local ‘independent’ surveyor appointed by cargo underwriters was controlling the stevedores and all three firms of tally clerks. He was also controlling the sale to the public for cash of rice on the quay, openly, in the evenings after discharge had stopped for the day. Ship’s staff were frightened to take photographic evidence of this, having been threatened with violence by stevedores. Seemingly, the stevedores, tally clerks and cargo interest’s surveyor were all involved in this organised theft.
Discharge port considerations
The problems associated with rice carriage to West Africa normally begin when the vessel arrives at the port of discharge. Stevedore mis-handing and tearing of bags is often a characteristic of the discharge process. Often receivers are claiming that the bags and contents are damaged even if the cargo is sound but the bag has but a small cut no longer than say 1 cm long. Clearly if stevedores at the loading port(s) use hand-hooks, then every bag perforated by such a hook during loading will be deemed damaged at the discharge port. The Master must issue letters of protest to cargo interests, the mate’s receipts should be suitably claused and the agents given written instructions only to sign bills of lading in accordance with the clauses on the mate’s receipts. Additionally, many photographs be taken and for each a note of date, time and specific location be recorded, and also what the problem is that the photograph is attempting to portray. Such evidence is extremely valuable for Owner’s P&I surveyor when attending at the discharge port.
Pilferage is, in varying degrees, common in many ports while tallying disputes can be exacerbated by the tendency of the receivers and their underwriters to appoint local surveyors and tally firms that conduct tallies ashore often in warehouses some distance from the port. It is also not uncommon for the receivers and the recovery agents acting for cargo underwriters to allege significant shortlandings of cargo or damage to the cargo shortly after the commencement of cargo operations and, as a consequence, seek security for claims that are no more than anticipatory and often for wildly exaggerated sums.
Demands for security with the implicit threat of arrest of the vessel also raise jurisdictional issues. Rice cargoes are insured in the commercial market, quite often in France. Not surprisingly, faced with regular claims under their policies the cargo underwriters frequently seek security for claims for loss or damage or the short landing of cargo that is subject to the jurisdiction of the French courts and French law irrespective of the of the fact that disputes under the contract of carriage, as evidenced by the bill of lading, are governed by some other law and subject to the jurisdiction of some other forum (often English law and arbitration in London). There are marked differences between French and English law. In particular, as a matter of English law FIOS (Free In Out Stowed) provisions incorporated from a Charterparty into a bill of lading should exempt the carrier from blame for loss or damaged proven to have been caused by stevedore mishandling if the charterer or shipper or receiver is responsible for the conduct of the stevedores, and short landing claims can be challenged if the carrier can establish that all the cargo loaded was discharged, notwithstanding a difference between the bill of lading and outturn figures.
What can be done by Owners and Carriers ?
- Contractual and Jurisdictional Considerations
The nature of this trade and its inherent problems mean that these issues should be anticipated and so far as possible addressed when the contract of carriage is being negotiated as well as by pre-planning at the discharge port. As to the former, and by way of example, the French Courts tend to consider the bill of lading and Charterparty as separate contracts. Therefore, notwithstanding that most common form of bill of lading used for rice carriage to West Africa is the "Congenbill", and that clause 1 on reverse of the Congenbill provides that "All terms and conditions, liberties and exceptions of the Charter Party, dated as overleaf, including the Law and Arbitration clause, are herewith incorporated", the French Courts are very reluctant to allow a carrier to rely on the FIOS or arbitration provisions of the Charterparty. As a consequence, a carrier may not have the protection, or may be exposed to greater risks than contemplated when the fixture was negotiated.
Therefore, an express statement on the face of the bill of Lading as to the governing law and jurisdiction for any claims made under the bill of lading (or if bills are to be issued by charterers, to require that charterers issue bills with such a clause on the face of the bill of lading) should improve the carrier's position if, when faced with a threat of arrest, security is provided that responds to a decision of a competent court, and proceedings are subsequently commenced by cargo claimants in the French Courts. Unfortunately, even in these circumstances, such clause will offer little protection against article 14 of the French Civil Code which gives jurisdiction to the French Courts if the claimant cargo underwriter is French.
If the French courts or courts of the jurisdiction of discharge are unlikely to decide any claims made under the bills of lading on the basis of the terms and conditions of the contract of carriage that the carrier intended when negotiating a fixture, express indemnities by charterers may provide protection or a means of recovering sums paid to the cargo claimants. For example an express indemnity against liabilities for short landing of cargo, or loss of or damage to cargo caused by stevedore mishandling of cargo, when the carrier would have had a defence to those claims if brought subject to applicable law of the Charterparty. - Practical Solutions - Cargo appearance, tallying, draught survey and crew involvement
These solutions are, however, subject to commercial reality and require careful drafting of the Charterparty terms and conditions. While they are useful tools, the nub of the problem is the appearance of the cargo in the hatches when first opened at the discharge port and the nature of the discharge operation from the vessel and means by which control can be exercised over that operation both in the sense of supervision and the recording of the quantity and condition of the cargo discharged. Both require practical solutions. In the case of the former, the stowage and ventilation issues discussed above are important, because a cargo that appears to be in a poor condition when the vessel’s hatches are first opened is an invitation to claim, whereas in the case of the latter the involvement of the vessel's crew can be key. This is particularly so if the crew are able to conduct their own tallies or closely monitor and then approve the tally sheets produced by the receiver's tally firm, provided always that those tallies are conducted ex the vessel's hatches and on the quayside in way of each hatch. Alternatively, a reliable independent tally firm can be instructed on behalf of the carrier and ship and cargo tallies compared at the end of each shift, again, provided always that the tallies undertaken on behalf of cargo are carried out ex ship's hatches and on the quayside in way of each hatch. Making sure that tallies conducted on behalf of the vessel and cargo are undertaken together ex the ship's hatches and cross checked at the end of each shift is also a means of managing the evidential problem of differing tallying figures when claims are pursued in the French Courts. If more than two survey reports are available, for example on behalf of the vessel, receiver and stevedores, the French courts tend to favour reports that have "similar findings". It is not unusual that on the completion of cargo discharge the receivers and stevedores tally figures are similar, and at odds with the vessel's figures.
When tallying the cargo a common means of creating a shortlanding is for tally clerks to record each sling as containing 40 bags whereas, in fact, a sling may contain more than 40 bags. Therefore, surveyors and/or the crew should be instructed to and carry out periodic spot-checks of slings to both to manage pilferage of cargo as well as a means of documenting the probable cause of any shortage on completion of discharge.
Although rice discharged in West Africa is a bagged cargo, draught surveys prior to the start and at the conclusion of discharge can also provide useful additional evidence to challenge the accuracy of the allegations of shortages of cargo made by the cargo receiver and underwriters. Similarly, the crew or surveyors acting for the vessel should ensure the stevedores do not mishandle the bags of rice and where they do so, appropriate and regular protests are issued. However detailed protests should be issued complaining that on a particular date and time, and stating in which holds a specific number of bags were torn, or emptied by the stevedores. If possible photographic evidence of the stevedores' actions should be attached to the protests. The Courts will give greater evidential weight to detailed protests in contrast to general protests or a protest that is issued using ready made stamps to place remarks on the documents signed on behalf of the vessel.
A further problem of varying degrees is theft of the cargo from on board the vessel by stevedores when ‘private’ parcels of variable sizes and weight are taken off the vessel at the end of shifts. Rice is often hidden in the stevedores' clothing or simply by taking bags of cargo, sometimes in full view of the watchmen appointed by the vessel’s agents. In this respect, at Lagos and Port Harcourt the risk of cargo lost in this way has successfully be reduced by employing private security guards, but as with cargo mis-handling, if there are thefts detailed protests should be issued.
While shipping rice to West Africa is likely to remain a fruitful ground for claims for the foreseeable future, there are preventative measures that owners and carriers can take to minimise their exposure.
Summary
Ship’s staff is recommended to follow the under noted guidelines:
Before loading
- Wash hold steel work and rinse thoroughly with fresh water.
- Clean and test hold bilge suctions, cover strainer plate with burlap.
- Ensure bilge sounding pipes, and other pipes in the hold are in good condition.
- Ensure openings in the tank top are secure and with effective rubber washers.
- Examine and hose test the hatch covers. Make good deficiencies if possible. Advise Owners if not.
During loading
- Monitor bags for wetness on the quay, in the cargo holds and in the barges.
- Send samples of apparently sound cargo to a laboratory for moisture analysis. 14% is the accepted maximum. Seek the advice of the P&I Club and local club correspondent as to which laboratory should be appointed.
- Do not accept, at face value, shipper’s declaration as to the moisture content.
- Issue letters of protest to shippers and charterers if a locally appointed government inspector is prevented from rejecting wet damaged bags by shippers or their servants.
- Issue letters of protest to shippers and charterers if the dunnaging and kraft paper or plastic sheeting is inadequate. Record the details and instructions of charterers’ cargo superintendent.
- Issue letters of protest if the stevedores use hand hooks and/or damage the cargo otherwise, clause the mate’s receipts accordingly and instruct agents to clause the bills of lading in accordance with the mate’s receipts.
- Monitor tally clerks during loading and check that they are counting the bags into the slings and not just the slings. Appoint a protecting tally survey on behalf of the ship alone, not a joint survey with the charterer or if sufficient crew are available they should tally the cargo.
- Ensure that the dunnage supplied is clean, dry, in adequate amounts and properly laid, protecting the ship’s steel. Issue written letters of protest if it is not. Take photographs of the prepared holds prior to commencement of loading.
- Ensure that adequate ventilation channels are constructed into each of the stows and that they are linked into the hold ventilation inlets.
- Reject any damaged cargo.
- Officers to take photographs of the loading in each hold daily and record these to computer at the end of each day. These should be captioned.
Thus, a photographic record for each individual cargo hold is made.
- Additionally, photograph barges and their hatch covers or tarpaulins, and any use of hand hooks by stevedores.
- Arrange for an electronic copy of the photographs, with captions, to be sent to ship owners/managers after loading has been completed.
- The master to understand any fumigation instructions and modify the hold ventilation around these instructions.
- Hatches should always be closed in good time to prevent the entry of rainwater. Note that rain can arrive suddenly and in heavy quantities, even outside the expected “rainy seasons” in West African ports, with apparently little warning and particularly at night.
The loaded passage
- Ventilate the cargo holds whenever it is both appropriate and possible. Maintain a ventilation record in which both internal and external wet and dry bulb temperatures are recorded (dew point). Open the hatch covers when appropriate.
- Sound and record hold bilges twice daily and maintain a record of any cargo hold bilge pumping.
- Before arrival, Master to confirm that owners/managers have appointed an independent firm of tally clerks to represent owners’ interest only (if insufficient crew available).
During discharge
- Upon first opening of the hatch covers, an officer to attend with local surveyors and photograph the surface of each stow and agree whatever is seen with attending surveyors. If damage is seen, immediately contact owners/managers to request the attendance of a P&I surveyor.
- If the surface of the stows are apparently sound, Master to produce a letter to that effect addressed to receivers and the agent requesting their agreement and counter signature. That letter should state that there was no evidence of water ingress via the hatch covers.
- Make sure that the attending tally clerk resp. surveyor firms have a letter of instruction from their clients and record which firms are working for charterers, receivers and the vessel. If any tally clerk / surveyor can not produce such a letter, he should be politely advised to return ashore and to return only when he can produce his written appointment instructions.
- If sufficient crew member are available, they should be instructed to tally the cargo.
- Bear in mind that the surveyor for the cargo interest will put pressure on the master to sign his outturn reports, but may be less than willing to sign the master’s outturn reports, which have been compiled by the master’s own protecting surveyor. The master should advise his local P&I correspondent and issue a letter of protest to the cargo interests to explain that he is agreeable to signing the outturn reports, with his remarks as necessary, in return for their signature, with remarks, on his own. Otherwise, he will not agree to countersign such outturn reports.
- If wet damaged bags are apparent, take photographs and make a record of their position within the hold relating to a reference point. If the apparently wet damaged bags are randomly located, record that this is the case. If a number of adjacent bags are found apparently wet damaged make a similar record.
- The master should issue written protests to the stevedore (or to his agent, for transmission to the stevedore) and charterer, regarding such things as poor cargo handling, theft and pilferage by dock labourers, the discharge of cargo onto wet quaysides, etc.
- The ship’s officers should be vigilant during the discharge to ensure that only the cargo marked for discharge at the particular port is actually discharged. They should also ensure that any unusual events are brought to the master’s attention, and that the position in the holds of any pockets of damaged cargo are noted (particularly with reference to mouldy/caked bags). Were they found around the edges of the stows, in all hatches or particular hatches? These points should also be discussed with the master’s surveyor.
- Sign tally clerks daily reports ‘for receipt only’.
- Issue a letter of protest to charterers and receivers if tally clerks are counting slings and not the number of bags.
- Issue a letter of protest to receivers and charterers if receiver’s tally clerks are counting the bags received at a location distant from the vessel.
- If petty theft or organised theft and sale of the cargo is evident, take discrete photographs of this and issue a letter of protest to receivers and charterers and advise owners.
- Hatches should always be closed in good time to prevent the entry of rainwater. Note that rain can arrive suddenly and in heavy quantities, even outside the expected “rainy seasons” in West African ports, with apparently little warning and particularly at night.
Bills of lading and charterparties
In conjunction with the notes summarised above, the following comments as regards bill of lading and charterparty issues can be made:
- Bills of lading should contain an express law and jurisdiction clause, for example all disputes to be referred to London arbitration, English law. At the very least, bills should expressly incorporate the arbitration and law clause contained in the charterparty. The date of the charterparty should be stated in the bill. English law is preferable on the basis that it allows the shipowner to contract out of responsibility for handling and stowing the cargo.
- Owners should try and include a clause in the bill of lading to the effect that the vessel and owners are free from risk, liability and expense whatsoever for loading, stowing and discharging the cargo. Terms such as “free in/out/load/stow/discharge” may only be sufficient to avoid responsibility for payment of such operations and may not be sufficient for owners to avoid responsibility to cargo interests under bills of lading for damage to cargo arising from such operations.
- Bills of lading should of course be claused for any cargo that is loaded not in apparent good order and condition.
- Owners should try and ensure that the charterparty makes the charterers fully liable for damage to cargo arising out of loading, stowing, and discharging the cargo. A good example is clause 5(a) of the Gencon charterparty form (as revised 1994).
- The owners should only really accept a provision that the master has a right to supervise/control and/or to intervene where stowage and/or the actions of stevedores are deemed by the master to affect seaworthiness and/or safety of the vessel.
- If the Inter-Club New York Produce Exchange Agreement (ICA) is incorporated into a time charter, owners should ensure that there is nothing in the charter that will make the ICA inapplicable and/or alter the apportionment of claims in respect of cargo handling from 100 per cent on charterers.
- If owners wish to avoid any responsibility for claims in respect of pilferage and condensation under the ICA, it should be borne in mind that the ICA requires “clear and irrefutable evidence” to support a case that one of the parties should be 100 per cent responsible. With condensation damage for example, owners would, at the very least, need to show that this was caused by bad stowage and not by bad ventilation practice. Appointing a court surveyor may be of assistance in terms of evidencing the cause of a particular loss/damage.
- The charterparty should also expressly provide that charterers are to provide, pay for and lay all dunnage. Any dunnage available on board should be expressly for use at charterers’ sole risk and responsibility.
- Owners should avoid any onerous terms in the charterparty as regards ventilation. It is also important to make charterers aware of the vessel’s ventilation capabilities/limitations (in many cases natural ventilation only) and that, due to weather, humidity and/or sea conditions, it will often not be possible to ventilate the cargo.
- Owners should avoid any onerous terms in the charterparty as regards control/avoidance of damage to cargo by stevedores and pilferage of the cargo. Practically speaking, it can be difficult, if not impossible, for the master to do anything to prevent stevedore damage and pilferage in West African ports.
- Owners should avoid any terms in the charterparty regarding the evidential effect of the description of the cargo in the bill of lading. Very often such terms have the effect of preventing owners from disputing the quantities stated in the bills of lading.
- Frequently the claimants in respect of rice shipments into West Africa are the voyage charterers. The owners may, however, be one or more charterparties removed from the voyage charterers. If cargo claims arising out of handling or stowage can not be avoided in the first instance under the bills of lading, it may be possible to show that the same claims fail for reasons of circuity. In other words, the claimants themselves will ultimately be responsible for claims in respect of cargo handling and stowage under the voyage charterparty. This will only be possible, however, where full responsibility passes down the charterparty chain. Owners can try to incorporate into their charterparty a provision whereby the charterers are to ensure that full responsibility passes down the chain to the ultimate charterers.
- Assuming the charterers are responsible for stowage, it is important for the master to appreciate that he should not intervene in the stowage or handling of the cargo unless of course he has safety/seaworthiness concerns. Otherwise, he should simply issue a protest to the shippers and charterers.
Conclusion
It can be seen that shipowners can do a great deal, both practically and contractually, to minimise their exposure to claims associated with bagged rice shipments from the Far East to West Africa and other similar shipments. If steps are not taken, shipowners can expect to continue to face large claims and possible disruption to their operations where arrests and/or unreasonable demands are made by cargo interests.
Typical cargo claims - Rice imported into West Africa
Ship attendances on behalf of owners’ P&I insurance interests, and dealing with complaints from receivers in respect of the condition of the rice cargo outturning from vessels, have been carried out in many West African ports. A number of common complaints are discussed below:
Wet damage
Invariably, there will be bags of rice showing signs of moisture and wet damage. These are often referred to as ‘mouldy’ or ‘caked’ by receiving tally clerks. Of course there can be many different causes for such bags to become wet and causing mould to develop. The cargo is invariably presented for loading in woven polypropylene bags. These are almost always of 20/25 kg. gross weight for ease of manhandling and stowage in the holds. In almost all cases these woven polypropylene bags are white in colour, and when the contents become wet, over a period of time they will evince dark stains and will give off a rotting smell and the contents will become caked. Obviously this raises the question as to where in the process of transportation the bags or their contents became wet. The appointed surveyor is tasked to determine the cause of the wetting by survey at the discharge port. The client, invariably a claims handler of a P&I club in which the ship owner has entry, requires the surveyor to produce a report with compelling evidence in order to allow the various parties to the contract of carriage to reach a settlement without resorting to legal action and attendant expenses. The collection of such evidence is often difficult and sometimes even dangerous as outlined previously. Turning now to the causes of wetting:
Wetting prior to shipment
In some of the ports and rivers in China and Vietnam, bagged rice will be delivered either from the quay if the ship is alongside a berth and from barges loading from the outboard side of the vessel, or if the vessel is at anchor within a river, then that cargo will be delivered by barges alone. At this stage it is very important for ship’s officers to closely monitor the condition of the bags being loaded into the vessel and to reject any which are showing signs of being wet.
In a number of Asian ports, government regulations require that an inspector is in attendance during the loading of bagged rice solely with the remit to examine the condition of the bags being offered for shipment and to reject any which the inspector believes to be wet. No reliance can be placed on these inspectors diligently doing what they are supposed to do.
For example, a vessel arriving in West Africa with some wet damaged bags appeared to have had a governmental inspector in attendance at the loading port where he had started to reject wet bags which were being offered from barges. In consequence this inspector was seriously threatened with physical violence by representatives of shippers. In response to that threat, the inspector spent the remainder of his time on board the vessel locked within the cabin allocated to him on board the ship. The Master of the vessel was able to provide the author with a statement to that effect however; this was not supported with a formal letter of protest from the Master via his agents to shippers’ interests (as he should have done).
In this case, the bags of rice were all loaded from barges and when enquiring of the Master as to the condition of the barges, it was learnt that the hatch coamings of the barges were over covered by a number of transversely arranged canvas and/or plastic tarpaulins; there were no steel hatch covers to these barges. The vessel was loading in a river in Asia during the local rainy season and clearly, transversely arranged canvas tarpaulins, albeit overlapping, will not prevent the ingress of rain into the cargo within those barges prior to shipment. Although the Master had submitted a statement to that effect, no photographic evidence of the condition of these barges could be produced; neither of the manner in which the cargo was over-covered to prevent damage caused by rain.
In another example, and by virtue of good records maintained in the deck cargo logbook, it could be proven that the loading of one particular hold had commenced at a certain tome from a barge which had not previously discharged any cargo to this, or any other vessel. Therefore, it was possible to show that what ever was placed on the tanktop of this particular hold had originated from the upper tiers of the bags in the barge adjacent to that hold. On reaching the tier on the tanktop during discharge, a uniform oblong area of bags spanning the full length of the tanktop and approximately one third inwards towards the centreline were all apparently uniformly wet stained, black and with rotten contents.
These circumstances enabled a robust argument that rainwater had wetted the upper tier of bags in the barge prior to shipment. Interestingly, the locally appointed surveyor in West Africa on behalf of cargo interests was adamant that this damage was proof of ingress of seawater via the hatch covers, even though all the bags directly above were found to be clean, white and dry. Clearly, the latter is an unsustainable argument. Additionally, simple tests for the presence of chlorides in the moisture indicated negative results.
There have been many examples of wet damaged bags deep within the holds of vessels during discharge and which from the photographic evidence alone could support a robust argument of inherent vice (i.e. the bags being wet prior to loading). It is customary during discharge operations that stevedores will excavate the cargo from beneath the area of the hatch square such that vertical walls in the cargo stow, port and starboard sides and forward and after ends will appear as discharge progresses. In such ‘walls’ is often found randomly located brown/black stained and wet damaged bags with clean, white and dry bags both above, beneath and on either side. Obviously, such randomly located wet damaged bags could not have become wetted through water ingress either from above or beneath during the loaded passage. Such bags can only have become wet prior to loading. However, locally appointed surveyors in Africa were unwilling to accept that logic and argued vehemently that this could only have occurred by means of sea water ingress via the hatch covers. Clearly, such an argument is not sustainable.
Another ship had loaded bagged rice in a Far Eastern port. The charterer had been obliged to load the cargo in vertically separated half hatches, which resulted in sheer faces of bags of 12-13 metres in height. Even at the load port, the unsupported faces began to slide and the master’s written letters of protest were not heeded. His protests were overruled – for operational reasons.
Matters came to a head later, in one of the West African discharge ports when one exposed face of cargo collapsed into the nearly empty aft section of the hold, unfortunately killing several stevedores. The authorities initially blamed the Master for the poor stowage, but with the clear evidence of his many written protests to the charterer on the subject, which had been disregarded, it was the charterer who finally accepted to place security for the tragic deaths.
Ship’s staff to collect evidence
Upon discharging rice in West Africa, it is usual for any dispute to have been ongoing for a number of days with the insurance interests of the ship owner (P&I club), initially relying upon their local correspondent to provide advice and reports. It is often the case that the local club correspondent has difficulty in collecting the necessary evidence and information and were he to do so thoroughly, then his continuing effectiveness working locally with cargo interests ‘surveyors’ could be highly prejudiced. For this reason, the local club correspondent may not be the most effective collector of evidence for the ship owner’s P&I interests.
When discharge has been ongoing for some time and the complaints have been developing for say eight or nine days, and by which time more than half of the cargo in the ship will probably have been discharged, the claims handler of owners P&I club may conclude that the likely size of the claim has grown to an extent that justifies flying an expert upon whom he relies to the vessel to deal with the problem and collect evidence as to cause. Arriving at the vessel say half way through discharge operations when a lot of evidence has been disturbed by the act of discharging, can present the surveyor with problems in collecting evidence as to cause(s). This is particularly the case if there is more than one cause.
Inevitably, when the appointed P&I surveyor arrives some days after discharge commenced, the evidence of the condition of the cargo at the uppermost tiers in each hold of the ship is no loner available and that evidence is crucial to support an argument that sea water did not ingress the holds via the hatch covers during the voyage.
For this reason, it is considered imperative that every ship discharging rice in West Africa or wherever have on board a quality electronic camera and that numerous photographs of the condition of the upper-most tiers of cargo in every hold are taken as soon as the hatch covers are opened at the discharge port. Ship’s staff should obtain the agreement of cargo interests’ surveyors and chief stevedores or a representative of receivers that the appearance of the cargo on first opening the holds was satisfactory and did not evince signs of water ingress during the voyage. The Master should also back up such agreements with a letter of cargo interests, stating the above and requesting cargo interests agreement and signature.
Additional information
Rice, especially new crop, is liable to heat and sweat, witrh consequent loss in weight of between 1% to 3%, but could be higher. Is susceptible to taint and should be stowed away from scented or odorous goods. Liable to damage by moisture due to improper ventilation. Rice that is damp or wetted quickly rots and generates heat, giving off a putrid smell. When damaged by sea water a not unpleasant smell is given off. When rice arrives in damaged condition, immediate steps are necessary for its treatment and/or disposal. The value will depend on the alternative use to which it can be put, such as brewing, seasoning, paste, fertiliser, etc. Time is an important factor as delay will aggravate the damage.
Boiled rice
May suffer loss in weight, but if properly milled and processed this loss should be small. Parboiled rice which has not been properly processed, dried down to 13% moisture content, will, on arrival, have a pronounced floury coating on the grains, and the sacks, in extreme cases, would show signs of sweat damage. This should assist the surveyor to tell whether the rice has been properly processed.
Broken rice
As for white rice below. Loss in weight may be considerably increased unless, at the time of shipment, great care is taken with sewing of the sacks.
Parboiled bran
Oil content about 23%. Subject to loss in weight.
Rice bran
Rice bran is combustible, and can create sufficient heat to create a fire. Certain carriers of the commodity would reject such a cargo if the temperature was more than 40°C at the time of loading. Rice bran will burn by itself and would probably ignite if brought into contact with fire from some other sources. There have been cases where it is known that rice bran has been the root cause of a fire.
White rice
May suffer loss in weight, is subject to heating and throws off moisture. Damage may result from insufficient dunnage and lack of ventilation. Grains of rice stick lightly together in the interior of the sacks. This is not necessarily due to wetting but may be the result of defective glazing. Rice which has been in stock for over two months is liable to infestation by weevil or web.
White rice bran
Oil content about 15%. Subject to loss in weight. The colour of the bran is no indication of damage, as colour may vary widely. Bran which has been damaged by heating has an unmistakable ‘cooked’ odour.
Rice dust (Boussir)
The chaff and waste of rice shipped in bags and commonly used as animal feed. Liable to heat.
Applications
On an international scale, rice is the most important cereal and serves as a staple food. Rice has its glumes removed in hulling mills and serves to produce flour as well as arrack and sake.
Risk factors
- Self-heating/Spontaneous combustion
- Odor
- Contamination
- Mechanical influences
- Toxicity / Hazards to health
- Shrinkage / Shortage
- Insect infestation / Diseases
See also: http://www.swedishclub.com/upload/Loss_Prev_Docs/Cargo/VIETNAMESE_RICE_REPORT.pdf