Ships & sizes
Double hull
Meaning
A double hull is an inner and outer shell around a tanker's cargo tanks, required for oil tankers under MARPOL to reduce spills after grounding or collision.
Double hull explained
Single-hull oil tankers were phased out of mainstream trade under MARPOL by 2010 after major spills. Charterers and terminals now accept only double-hull tankers for oil cargoes.
Related terms
MARPOL
MARPOL is the IMO's International Convention for the Prevention of Pollution from Ships, covering oil, chemicals, sewage, garbage and air emissions.
Vetting
Vetting is an oil company's or charterer's risk assessment of a tanker, using inspection reports and history, before agreeing to charter it or accept it at a terminal.