I've taken a gander through the previous entries, but didn't find anything similar, so I thought I'd ask ...
I am trying to discover how long it takes for natural gas being pumped (the main gas valve on a stove being opened fully, and the burners opened) into a 26' x 12' room with 12' ceilings and standard ventilation to get to a point where an electrical spark can ignite it. I know the gas rises, and it takes very little actual gas to become a hazard, but how long would it take time-wise? A few seconds? A couple of minutes?
The story is set 50 years in the future, and we're assuming the gas lines and industrial gas stoves haven't changed significantly from today's.
I've Googled: Natural gas leaks, natural gas hazards, calculating vapor pressure, natural gas safety, natural gas psi, natural gas explosions, natural gas fires.
Thanks for any help you can give!