Definition: Chemical tanker
Designed to carry relatively small parcels of higher value chemicals, such as acids or polymers. Ships are typically relatively small, up to around 25,000 dwt. Chemical tankers are classed according to categories dictated by the International Maritime Organisation (IMO) that classes chemicals according to the level of hazard they represent. IMO class I represents the greatest hazard and requires ships with sophisticated tanks and cargo handling systems, often manufactured from stainless steel. IMO class II represents a lower class of hazard with relatively normal tanks and cargo handling systems. IMO class III refers to low hazard chemicals, such as many petroleum products. There is a blurring of the distinction between products and chemical tankers for these lower classifications (Lloyd’s Register’s classification "chemical/products carrier" normally refers to a products tanker rather than a chemical tanker).
First Marine International Limited, "Overview of the international commercial shipbuilding industry, Background report", disseminated on the Web site of Directorate-General "Enterprise and Industry" of the European Commission, May 2003