Sheltering in a house cellar might give u a few concerns as the house burns on top of you, but that is more to do with mechanical ventilation then structural collapse than oxygen starvation
Seen and heard of a few 'bunkers' built under houses. Better regarded as a "cellar".
Trouble is that instead of just a 20 or 30 minute heat pulse, they have to have air &
insulation to withstand 1 or 2 hours until the house goes out. Even then, they are
buried under a pile of hot ashes, dutch oven style, possibly for days (it's been 12
days now & they still haven't checked every destroyed house.)
Methinks a cellar of any sort should be regarded like any other room - aim to be out
of it before the house starts collapsing. Anyway, CFS advice regarding sheltering in
houses is not to hunker down in a room, but to actively patrol the interior, putting
out interior ignitions early.
While on the subject of bunkers & shelters, there was a bloke on the wireless the
other day who, in the early '90s, came up with a shelter made from the same sort of
material as the space shuttle heat tiles. Tested in a 1200C oven, the interior
rose <2degC after 30 mins.
Tested in a live fire gas prop appliance mock-up, where the shelter is the water
tank, a crew of 4 were able to enter it in 14 seconds. After 20 minutes of direct
flame inpingement, the crew were complaining the water was "cold & can we get out
now please?" Internal air temp had risen 2C & water temp by 0.5C.
Said the tank shelter was reviewed by the CFA & rejected because "It would give
crews a false sense of security".
cheers