These recommendations are for liquefied petroleum gas (LPG) carriers and liquefied natural gas (LNG) carriers. For the purposes of this document, the term LPG carrier refers to liquefied gas cargoes carried between the temperature range of 0°C to -104°C. These recommendations do not apply to existing ships, and there is no suggestion that existing ships should be altered.

It is recognised that some new gas carrier designs may not be able to conform to all of the recommendations in this document, however, this document is intended to serve as a starting point with a view to minimising differences as much as possible.