Which form of ventilation is the most prone to recirculation?
Negative-pressure
What is the upward draft caused by smoke rising through vertical openings in a multi-story building?
Stack effect
What is the minimum measurement for a ventilation opening cut in a pitched roof?
4 ft. by 4 ft. (1.2 m by 1.2 m)
When smoke in a building cools and forms layers, it is said to __________.
Stratify
What is the minimum measurement for a ventilation opening cut in a flat roof?
4 ft. by 8 ft. (1.2 m by 2.4 m)
Properly performed ventilation is most likely to reduce __________.
Smoke damage
Which ventilation technique relies on the principle of pressure differentials?
Positive pressure