The chemical tanker shipping industry uses a specialized vocabulary drawn from maritime law, international regulations, commodity trading, and naval architecture. This glossary defines the key terms used across this resource.
A
- Affreightment
- A contract by which a shipowner agrees to carry cargo for a merchant. Contracts of Affreightment (COAs) are a major commercial arrangement in chemical tanker shipping.
- Annex II (MARPOL)
- The annex to the MARPOL convention that specifically regulates pollution from Noxious Liquid Substances (NLS) — the cargo category covering most chemical tanker cargoes.
B
- Ballast
- Seawater taken into a vessel's ballast tanks when cargo is not being carried, to maintain vessel stability. Ballast water management is subject to international regulation.
- BIMCO
- Baltic and International Maritime Council. A leading international shipping industry organization providing standard contracts and industry information.
C
- Chemical Parcel Tanker
- A specialized tanker vessel designed to carry multiple different liquid cargo parcels simultaneously in segregated tanks, typically with 13 to 31 separate cargo compartments.
- COA (Contract of Affreightment)
- A long-term contract committing a shipowner to carry a specified volume of cargo over a defined period. A cornerstone of commercial planning in the chemical tanker sector.
- Coated Tank
- A cargo tank whose interior surface is coated with a protective material (zinc silicate, epoxy, or similar) to prevent corrosion and facilitate cleaning.
D
- Deadweight Tonnage (DWT)
- The total weight a vessel can safely carry when fully loaded, including cargo, fuel, fresh water, ballast, provisions, and crew. DWT is the primary measure of tanker capacity.
- Double-Hull
- A ship construction method in which the cargo tanks are separated from the outer hull by a void space, providing protection against cargo loss in the event of grounding or collision. Mandated by MARPOL for tankers.
I
- IBC Code
- The International Bulk Chemical Code, issued by the International Maritime Organization. The primary international standard governing the design, construction, and operation of chemical tankers.
- IMO
- International Maritime Organization. The United Nations specialized agency responsible for international shipping safety and environmental regulations.
- IMO Type II / Type III
- Classification categories for chemical tankers under the IBC Code, based on the hazard level of cargoes the vessel may carry. Type II vessels handle moderately hazardous substances; Type III handle less hazardous cargoes.
- ISM Code
- International Safety Management Code. An IMO standard requiring shipping companies to establish and maintain a systematic Safety Management System (SMS).
- ISO 9001
- The international standard for quality management systems, commonly sought by chemical tanker operators as evidence of documented quality processes.
M
- MARPOL
- International Convention for the Prevention of Pollution from Ships. The primary international treaty governing maritime environmental protection.
- MTPA (Million Tonnes Per Annum)
- A measurement of cargo volume commonly used to describe fleet or route throughput capacity.
N
- NLS (Noxious Liquid Substances)
- The MARPOL Annex II category for liquid bulk cargoes that are potentially harmful to the marine environment.
O
- OPA-90
- U.S. Oil Pollution Act of 1990. U.S. legislation that mandated double-hull tanker construction, vessel response plans, and financial responsibility for oil spill cleanup.
P
- Parcel Tanker
- See Chemical Parcel Tanker.
- Port State Control (PSC)
- The inspection of foreign ships in national ports by the host country's maritime authority to verify compliance with international regulations.
S
- Segregation
- The physical separation of different cargo parcels in a chemical tanker using dedicated tanks, piping, and pump systems to prevent contamination between incompatible cargoes.
- SMS (Safety Management System)
- The documented safety management system required by the ISM Code, covering procedures, responsibilities, emergency response, and continuous improvement.
- Stainless Steel Tank
- A cargo tank constructed from stainless steel, capable of carrying a wide range of chemical cargoes including corrosive substances that would damage coated carbon steel alternatives.
- STCW
- Standards of Training, Certification and Watchkeeping for Seafarers. The international convention setting qualification requirements for officers and crew.
T
- Tank Cleaning
- The process of washing and preparing cargo tanks between consecutive cargo parcels. Procedures vary based on the cargo sequence and the cleanliness standard required.
- Tramping
- Vessel operation that follows cargo wherever it is available, as opposed to fixed service patterns. World-wide tramp chemical tankers serve spot market cargoes.
V
- Vessel Response Plan (VRP)
- An emergency response plan required by OPA-90 for tankers operating in U.S. waters, documenting procedures and resources for responding to an oil spill scenario.