Naphtalene
From Cargo Handbook - the world's largest cargo transport guidelines website
White crystalline, volatile flakes with strong coal-tar odor.
A petroleum product which gives off an unpleasant camphoric scent and may release inflammable gases. Above 80°C explosive vapor-air mixture (0.9-5.9%) may be formed. Insoluble in water.
Produced as crystals, flakes, powder, or as liquid, the dust clouds from naphthalene may cause explosions. Stowage must be away from odor-sensitive goods, like coffee, foodstuffs and allied products. Good packaging is essential to container cargo vapor (if heated) which can attack the interior paintwork of containers. Hermetically sealed drums are considered to be the best option.
Contact with anything liable to sparks must be avoided.
Hazard:
UN 1334, 2304 Class 4.1
EC 202-049-5