Any fire that reached full room involvement has made that transition.

I use burned baseboards as the indicator. If the fire dept reports seeing fire blowing out the windows, that's also a reliable indicator that the fire has made the transition from fuel controlled to ventilation controlled.

Flashover is the phenomenon that usually takes place at the trasnsition. Flashover is more or less uniform. But immediately after flashover, the fire becomes decidedly less uniform.

Idiots (hacks) like to point out less uniform features to declare that because they see non-uniform damge, flashover must not have occurred. Therefore, they need not consider the possibility that the "irregular patterns" they see were not caused by anything other than ignitable liquids. The question we need to ask is not "Did flashover occur?" but "Did the room become fully involved?" If the room was fully involved, it became a ventilation controlled fire.

Unfortunately, there are still hacks who get away with declaring that, based on the alleged "non-uniformnity" of the burn, it must have been caused by a flammable liquid. Therefore, they must be "pour patterns." Judges, who have no knowledge of fires, let them get away with this BS routinely.

When will the courts ever stop letting hacks testify? Probably not in my lifetime. God forbid a judge should appear "soft" on "crime."

John Lentini, CFI, D-ABC
Fire Investigation Consultant
Florida Keys
[www.firescientist.com]