Darryl&Rita wrote:
Check your math. The lower explosive limit for propane is 2.1%, not 4.1% of your 24:1. Upper limit is 9.5%, which is where there isn't enough O2 to sustain a flame front.
You are of course correct, HOWEVER, at 2.1% (the bare minimum to support ignition) there would be just a bang, possibly some minor damage, roof vents, a window maybe.
To get a result as seen above would require a full fuel load, 4% or more.
But even at 2% there would still be a minimum of 1 cubic yard of pure propane vapour inside, you would NOT need an alarm to let you know that was the case.
