*Bk 29- Smoke Removal Flashcards
The current methods that are utilized to provide pressurized ventilation with portable blowers are ________ and _________ pressure ventilation.
Negative and positive
What are the two basic methods that are utilized to pressurize a contaminated area to enhance or direct the travel of contaminants to the exterior?
Natural and mechanical positive pressure ventilation
During negative pressure ventilation, the blower is placed inside or outside of the structure?
Inside
For positive pressure ventilation, is the blower placed inside or outside of the structure?
Outside
Compared to negative pressure ventilation, positive pressure ventilation is approximately how much more effective at removing contaminants from a building.
Twice
Positive pressure is most efficient when the exhaust opening (heat hole, window, door, etc.) is between ________ to ________ the size of the entrance opening
3/4 to 1 3/4
If a gasoline powered blower is being utilized and an exhaust odor is noticeable inside the building or area to be ventilated, this is an indicator of what?
That the exhaust opening is not big enough
Positive pressure has proven effective AGAINST winds (leeward to windward) of up to ______ mph
25
The effective implementation of positive pressure is dependent on what 5 things?
- Entrance opening
- Airflow between openings
- Exhaust openings
- Weather
- Training/communication
A single blower should be positioned so the cone of pressurized air ________ covers the entrance opening
Just
Tilting blowers at angles more than the manufacturer designed will result in what?
Lack of lubrication to the crankshaft
When blowers are placed in series, the first blower should be placed how far back from the opening?
2 feet
When blowers are in series, the rear blower augments the front blower by what percent?
10%
If two blowers of unequal CFM are utilized in the series position, how should they be lined up?
Larger blower up front, smaller blower behind
If the area in front of an entrance opening is limited to three or four feet (i.e., raised porch), place the smaller blower in the entrance opening and the larger blower how many feet back from the door?
3-4ft