Firefighter ProBoard Practice Test 2026 – All-in-One Guide to Achieving Exam Success!

Flashover is the rapid transition where the room’s contents reach ignition temperature and the fire suddenly involves the entire space. Signs pointing to this dangerous shift are a noticeable, abrupt rise in temperature, smoke that becomes dense and is pushed out of openings under pressure, and flames appearing at the ceiling as the upper layer is ignited. These cues show the heat and gas buildup reaching a critical level, signaling that conditions can deteriorate quickly.

Water from a hose stream isn’t a sign of flashover. It’s a firefighting action used to cool and suppress the fire; its presence doesn’t indicate that flashover is occurring.