14- Truck Company S&T- Special Ventilation Operations

Question 1

As is true in other types of buildings, the greatest number of lives can often be saved in high-rise buildings by:

Answer 1

An aggressive fire attack.

Question 2

____ ____ is the natural vertical movement of heat and smoke (convection) in tall structures.

Answer 2

Stack Effect

Question 3

________: The tendency of heat, smoke, and other products of combustion to rise until they encounter a horizontal obstruction. At this point they will spread laterally until they encounter vertical obstructions and begin to bank downward.

Answer 3

Mushrooming

Question 4

_________: Formation of smoke into layers as a result of differences in density with respect to height with low density layers on the top and high density layers on the bottom.

Answer 4

Stratification

Question 5

Most PPV blowers positioned at street level are effective up to about __ floors.

Answer 5

22

Question 6

In high-rise buildings, dedicating one stairway for ____ and another for _____ is critical.

Answer 6

Evacuation ; Fire Attack

Question 7

Just as HEAT transfers from a hot object to a colder object until their temperatures are equal, _____ transfers from an area of higher ____ to another of lower _____ until they equalize.

Answer 7

Pressure

Question 8

In a closed compartment, the point where the interior pressure is equal to the pressure outside the space is called the ___________.

Answer 8

Neutral Pressure Plane

Question 9

As the distance away from the neutral pressure plane increases, the pressure difference also increases- _____ above the plane and _____ below the plane.

Answer 9

Positively above the plane
Negatively below the plane

Question 10

Assuming that the structure is closed, a neutral pressure plane exists at the level of ambient atmospheric pressure- usually between __ % and __% of the building height.

Answer 10

Between 35% and 50%

Question 11

Wind can have a major influence on stack effect because of its ability to produce a ____ pressure on the windward side of the building and a _____ pressure on the leeward side.

Answer 11

Positive pressure on windward side
Negative pressure on leeward side

Question 12

__________ are intended to limit the spread of fire within a building by releasing heat and smoke to the outside before the fire mushrooms throughout the building.

Answer 12

Automatic Roof Vents

Question 13

Automatic roof vents take advantage of the fact that fire gases rise due to convection. Therefore, these vents are placed:

Answer 13

At the highest point of the roof.

Question 14

Curtain Boards (aka “draft curtains”) generally extend down from the underside of a roof at a distance equal to at least __% of the vertical distance from the floor to the roof but NOT LOWER than __ feet above the floor.

Answer 14

At least 20% of the vertical distance from floor to roof

Not lower than 10 feet above the floor