Liquefied Gas Carrier

Home page||| LNG handling ||| LPG handling||| Other Gas products||| Fire & Safety||| Emergency response |||

LPG & Ammonia cargo handling -Precautions on cargo operation

Carrying and handling liquefied gas cargo onboard poses significant potential hazards including risk of injury or death,threats to environment and each person working on a gas carrier and terminal ashore needs to understand the risks involved, obtain the necessary training and take all the needed precautions.



Prevention of Cargo Leaks

(1) The most important thing on board LPG & Ammonia carriers is to prevent leaks of cargo in the form of liquid or gas.

(2) Although the leak of cargo does not cause sea pollution like petroleum, it generates the danger of fire and explosion as it spreads to a large area as cargo evaporates producing a large amount of gas (260 times in the case of propane; and 230 times in the case of butane, 900 times in the case of ammonia).

(3) If a large amount of cargo is involved in the leak, it may cause such serious secondary accidents which are not confined to the vessel only but which may affect the environment as the brittle fracture by excessive cooling of the vessel hull, outflow of cargo, dispersion of gas, ignition and explosion.


Prevention of Damage to the Hull owing to Brittle Fracture

If the liquid cargo happens to leak, the vessel should prevent fire and damage to the vessel due to its low temperature. In order to protect the vessel hull from being damaged, it is necessary to evaporate the leaked liquid as soon as possible and also disperse such gas for the prevention of fire.
LPG carrier sea passage

Fig: LPG carrier at sea



Cargo Transfer

Cargo transfer is performed not only in the form of liquid but also in the form of gas, and when vapors are transferred by opening a manifold gas valve where the vessel line and shore line are connected, crew members should be aware that this is also a form of cargo transfer.


Disposal of Boil-off Gas

Crew members should perform cargo handling operations taking into consideration the disposing method of BOG (boil-off gas) which is generated at all times in cargo tanks with liquid left over.



Related Information:

  1. Procedure for water washing after Ammonia cargoes

  2. Safety guideline for changing previous cargo


  3. Inerting of Cargo Tanks prior loading LNG cargo


  4. Risk of Overfilling of Cargo Tank during Loading


Procedure for loading Liquefied Gas Cargoes

Procedure for Cargo Conditioning in Liquefied Gas Carriers

Cargo Transfer between Vessels (STS Operation)

Procedure for segregation of Liquefied Gas Cargoes

Procedure for Stripping Liquefied Gas Cargoes

Procedure for Changing Liquefied Gas Cargoes

Displacing Atmosphere with Inert Gas (Inerting)



Preparation for Cargo Transfer

Procedure for discussion prior cargo transfer

Procedure for commissioning the cargo systemCargo emergency shutdown requirement for liquefied gas carrier Gas analyzing equipment



External links :

  1. International maritime organization








// Home page/// LNG handling /// LPG handling/// Sea transport /// Gas products///

Cargo work ///Fire precautions ///Health hazards ///Safety Precautions

///Emergency response ///




Copyright © Liquefied Gas Carrie.com All rights reserved.


The content published in this website are for general reference only. We have endeavoured to make the information as accurate as possible but cannot take responsibility for any errors. For latest information please visit www.imo.org . Any suggestions, please Contact us !

///Links &Resources // Terms of use/// Privacy policy///Home page///