TST chapter 12

Question 1

positive pressure ventilation (PPV)

Answer 1

method of ventilating a confined space by blowing fresh air into space

Question 2

negative pressure ventilation (NPV)

Answer 2

using smoke ejectors to pull smoke out of the structure…placed in windows ..doors ..or roof vent holes

Question 3

masonry and concrete walls

Answer 3

exterior walls usually range from 8 to 12 inches or more in thickness depending upon material used

Question 4

veneer-over-frame walls

Answer 4

frame walls in which 2x4 inch or 2x6 inch wood or metal studs are covered with a layer of plywood or OSB board for shear strength

Question 5

important factors that must be considered in a plan for horizontal ventilation include…

Answer 5

• location of fire
• wind direction and speed
• location of ventilation openings

Question 6

windward

Answer 6

unprotected side …the direction from which the wind is blowing

Question 7

Leeward

Answer 7

protected side…the direction opposite from which the wind is blowing

Question 8

Churning

Answer 8

movement of smoke being blown out of ventilation opening only to be drawn in…..because the opening around the smoke ejector has not been sealed…..also called recirculation.

Question 9

Hydraulic ventilation (fog stream)

Answer 9

fog stream directed thru window or doorway with a 60 degree pattern covering 85 to 90 percent of the opening provides best results