Inert Gas System onboard
The IG system spreads the inert gas (IG) over the oil cargo-hydrocarbon mixture which increases the lower explosion limit LEL (lowest concentration at which the vapours can be ignited), simultaneously decreasing the Higher explosion limit HEL (Highest concentration at which vapour explodes).
When the concentration reaches around 10 %, an atmosphere is created inside the tank in which hydrocarbon vapours cannot burn. The oxygen concentration of inert gas is kept around 5% as a safety limit.
Also Read: Components of Inert Gas system: 13 Crucial Ones.
Ref : Marine insight website
