Book 29 Ch 3 Smoke Removal Flashcards
VENTILATION METHODS: There are two basic methods, These are ________ and
____________ positive pressure ventilation
Natural
Mechanical
The current methods that are utilized to provide pressurized ventilation with portable blowers are __________ and __________ pressure ventilation
Negative
Positive
NEGATIVE PRESSURE VENTILATION - To ventilate the building, the door is opened and a blower is placed _________ the building to exhaust the contaminants
INSIDE
POSITIVE PRESSURE VENTILATION - To ventilate the building, the door is opened and a blower is positioned __________ the building
OUTSIDE
Compared to negative pressure ventilation, positive pressure ventilation is approximately ________ as effective at removing contaminants from a building
Twice
Blowers must be positioned so the cone of air issued from a blower will ____________ cover the entrance opening to eliminate contaminants being forced back through the “unsealed portions” of the entrance opening and being reintroduced into the pressurized building
Completely
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
1 3/4
If a gasoline powered blower is being utilized and an ________ odor is noticeable inside the building or area to be ventilated, this is an indicator that the exhaust opening is not large enough
Exhaust
If it is not possible to utilize the prevailing wind as an advantage, positive pressure has proven effective AGAINST winds (leeward to windward) of up to ___ mph; efficiency will be reduced accordingly
25
These two factors will regulate the distance between the blower and the entrance opening:
1. ______ of the opening
2. _____ of the blower
Size
CFM
Small blowers (18”) need to be moved ________ from entrance openings while larger blowers (24”) can be placed ________ to entrance openings to properly cover the opening with pressurized air
Back
Closer
In Series - For standard entrance openings ___________ effectiveness is achieved by placing two blowers in series (in-line) with each other
Maximum
When using two blowers in series, the second increases the front blower capacity by ___%
10
When using two blowers in series, place the ______ blower about __ feet back from the entrance opening and utilize the _______ blower behind that
Large
2
Smaller
If the area in front of an entrance opening is limited to __ feet or __ feet (i.e., raised porch), place the smaller blower in the entrance opening and the larger blower __ to __ feet back from the door
3 or 4
3 or 4