WelshGas
Retired after 42 yrs and enjoying Life.
Super Poster
Lifetime VIP Member
Yes, they supposedly pick up butane/propane but not that useful unless the whole van is full of those gases, which are heavier than air so likely to be at floor level and the instructions were to fit midway up the wall. You would smell the " odour agents- mercaptans " included in the gas canister before the alarm went off.Those alarms usually can detect propane and LPG so not completely useless hopefully. Not sure exactly what narcotic gas is? Laughing gas?
We had Narcotic gas/vapor analysers in the Operating Theatres - about £5000 + /unit for a standalone unit, so I don't know how a £48 unit compares. Well I do know - next to useless.