NIOSH has just published a new report about the dangers of engineered wood in floor systems that is good reading for all firefighters. The header box in the article reads:
Fire fighters are at risk of falling through fire-damaged floors. Fire burning underneath floors can significantly degrade the floor system with little indication to fire fighters working above. Floors can fail within minutes of fire exposure, and new con¬struction technology such as en¬gineered wood floor joists may fail sooner than traditional con¬struction methods. NIOSH rec¬ommends that fire fighters use extreme caution when entering any structure that may have fire burning beneath the floor.

OK it is important to recognize that the report is years behind what we should have known but at least it is a reminder of lessons we should all remember