Action in case of Inert Gas Failure ?

• Flame screens are checked to ensure they are fitted and in good condition.
• Valves on the vent mast risers are opened.
• No dipping, ullaging, sampling or other equipment is to be introduced into the tank unless essential to the safety of the operation. If it is necessary for such equipment to be introduced into the tank, it is to be carried out only after at least 30 minutes has elapsed since the supply of inert gas to the tank has ceased.
• All metal components of any equipment to be introduced into the tanks must be securely earthed. This restriction is to be applied until a period of 5 hours has elapsed since the supply of inert gas into the tanks has ceased.
• Company permission has been granted.

Points to pounder :

If it becomes necessary, on a product and chemical carrier, to clean tanks while the inert gas system is out of operation, the precautions detailed in the ISGOTT Guide must be observed.

Should a vessel experience a partial failure of the inert gas system during discharge of cargo and the vessel is unable to supply sufficient inert gas to keep the tanks inerted at a positive pressure of at least 100mm water gauge, then the cargo discharge rate must be reduced to a level at which a positive pressure of 100mm water gauge can be maintained.