After ventilating for a while, how can the crew check whether it is now safe to use anything electrical or to light the stove again?

A. Check carefully for any remaining smell, especially down low near the bilge where heavier gas would have settled; if there is any doubt at all, do not use the stove or any electrics — get the system checked by a qualified person before using gas again

B. Assume it is automatically safe once the smell can no longer be noticed at nose height standing up

C. Light a match near the bilge to test whether gas is still present

D. Use an electrical hairdryer pointed into the bilge to check for a reaction

A. Light the stove quickly to burn off the smell before it gets worse

B. Switch on the cabin lights to get a better look for the source of the smell

C. Ignore a faint smell since it is probably nothing serious

D. Never light anything, switch on anything electrical, or create any spark near the smell — gas vapour, especially LPG, is heavier than air and can build up invisibly in the bilge, ready to ignite from the smallest spark

A. Leave the gas supply exactly as it is and deal with it later

B. Only turn off the cooker control knob, leaving the main bottle valve open

C. Turn the gas supply up higher to "flush it through" faster

D. Turn off the gas at the bottle itself (the main valve), not just at the cooker — this stops any more gas flowing into the system while the leak is investigated