"... it is usually the smoke that kills people, not the fire."
Approved Document B (2006) acknowledges the importance of good smoke ventilation practice:
"the primary danger associated with fire in its early stages is not flame but the smoke and noxious gases produced by the fire. They cause most of the casualties and may also obscure the way to escape routes and exits. Measures designed to provide safe means of escape must therefore provide appropriate arrangements to limit the rapid spread of smoke and fumes."