12 Horizontal Ventilation

Question 1

Advantage of electric fans over gas powered fans

Answer 1

Electric is quieter and don’t produce exhaust, preferred over gas, though gas powered may move more air

Question 2

Disadvantage of hydraulic blower fan

Answer 2

Can add water damage if they leak

Question 3

Flexible ducting for vent fans can be used in what type of fans

Answer 3

Both negative and positive pressure fans.

Question 4

Two types of ducting

Answer 4

Flexible translucent plastic up to 24” in diameter kept open by pressure pushing through it
Treated fabric over metal coil kept open by metal coil

Question 5

Electric blowers can be placed inside the building to expel smoke out through ducts. If electric is not available, a gas blower should be positioned

Answer 5

Outside the building with ductwork going into the building, blow fresh air through duct into the compartment, forcing out the smoke with positive pressure

Question 6

Vent blower ducts are used in what situations.

Answer 6

After the fire is controlled, moving smoke out that is cold, move smoke out of a compartment without pushing it through the rest of the space, contaminating clean spaces.

Question 7

Vent ductwork can be used to remove smoke from confined spaces like attics, and basements, it can also provide fresh air for

Answer 7

Crews working long term in confined spaces, vaults, sewers, silos.

Question 8

When ejecting smoke what needs to replace the smoke removed

Answer 8

Fresh air needs to replace smoke removed in order for it to work.

Question 9

When working or venting below grade, what should be monitored

Answer 9

Air quality for possible heavier than air gasses.

Question 10

Fixed window

Answer 10

Doesn’t open, sometimes flanked or paired with double hung or casement windows

Question 11

Single and double hung windows

Answer 11

Single hung windows only have one moveable section
Double hung, both sections or halves are moveable.
Only half the window space is available for ventilation in both

Question 12

Casement window

Answer 12

Outward swinging hinged sashes opened by hand crank. Double casement windows are side by side, separated by a mullion.

Question 13

Mullion

Answer 13

A vertical division between multiple windows or a double door opening.

Question 14

Horizontal sliding windows

Answer 14

Two or more horizontal sashes, one is fixed,sash can be slid sideways or removed from inside.

Question 15

Awning windows

Answer 15

One or more top hinged, outward swinging sashes.

Question 16

Jalouise windows

Answer 16

Narrow horizontal panes of glass in pivoting bracket at end. Oliver like windows. Difficult to open from outside without breaking.

Question 17

Projected windows.

Answer 17

Aka factory windows. May be top or bottom hinged, outward swinging. Like windows at Kristina’s school

Question 18

Hopper windows.

Answer 18

Bottom hinged inward swinging sashes

Question 19

Energy efficient windows

Answer 19

Double or triple glazed. Space between lanes are filled with inert gas.

Question 20

Energy efficient windows are commonly referred to as

Answer 20

Thermal windows

Question 21

Thermal or energy efficient windows hold more heat and break later than conventional, causing what during a fire

Answer 21

Longer time to self vent, promote spread and intensity of fire, longer time for passerby to notice

Question 22

When horizontal vent is needed, windows that resist opening from the outside usually can and should be

Answer 22

Broken out.

Question 23

For venting Lexan type windows that resist breaking, the fastest way is

Answer 23

To remove the entire frame and window, by cutting out if needed, than breaking.

Question 24

Doors can make horizontal ventilation very effective because

Answer 24

Their opening is larger than windows.

Question 25

Doors that need to be opened for vent should be blocked open instead of removed because

Answer 25

Blocking allows the door to be closed later if the vent profile needs to be changed.

Question 26

Mot common type of exterior doors used for tactical venting

Answer 26

Swinging doors
Sliding doors
Overhead doors
Roll up doors

Question 27

Two types of sliding doors

Answer 27

Exterior sliding doors, interior sliding fire doors.

Question 28

Before fire doors are reopened, firefighters must make sure of what

Answer 28

That there is no longer any danger of fire spread through the door.

Question 29

Interior sliding fire doors should be blocked open because

Answer 29

If they activate during operations, they can trap firefighters or kink hose lines

Question 30

Telescoping doors have two skins separated by air space at least how wide

Answer 30

2”, gradually getting larger as you move up so there is more space for the lower door components to nest inside, can be more than 13 inches at top

Question 31

Target hazard

Answer 31

Facility where there is a great potential likelihood of life or property loss in the event of an attack or disaster or fire

Question 32

Stem wall

Answer 32

Wall between foundation footing and first floor.

Question 33

In the case of fire walls, ventilation might need to be performed on what side

Answer 33

Both sides of the fire wall

Question 34

Generally firewalls should not be breached for ventilation because

Answer 34

It can feed fire and spread fire to protected parts of the building.

Question 35

Masonry and concrete walls can be what range in thickness

Answer 35

8-12” or more

Question 36

Exterior insulating finishing systems EIFS, can be as thick as

Answer 36

One foot

Question 37

EIFS can be detected by

Answer 37

The hollow sound made when tapped by a tool

Question 38

Wall ties

Answer 38

Thin corrugated pieces of metal that attach exterior masonry veneer

Question 39

Horizontal ventilation is usually done by opening a window near the seat of the fire and using what as an inlet opening for air

Answer 39

The entry point or door

Question 40

Important factors to be considered in a plan for horizontal vent

Answer 40

Location of fire
Wind direction and speed
Location of vent openings

Question 41

Exit opening is usually made where

Answer 41

As close to the fire as possible and on opposite side of from where fire attack is made

Question 42

It may be possible to combat windward side pressurization from wind to the fire by

Answer 42

Using ppv on the leeward side

Question 43

The most often used horizontal ventilation

Answer 43

Natural

Question 44

Interior doors may by systematically opened and closed one at a time to achieve

Answer 44

Controlled ventilation of different compartments

Question 45

Screens curtains or blinds should be removed from windows when venting because

Answer 45

They may hinder airflow.

Question 46

Compared to inlet openings, how large should exit openings be

Answer 46

Exit openings should be about twice as large as inlets

Question 47

If a fire is on the leeward side, what windows must be opened first

Answer 47

The tops of the leeward windows to let smoke out first, then windward side to facilitate the movement.

Question 48

Smoke ejectors were designed for

Answer 48

Drawing out heat and smoke and to withstand the temperature and contamination, except flames can damage it

Question 49

Unless smoke ejectors are equipped with intrinsically safe motors, they should be used after the fire is out because

Answer 49

They might ignite fire gasses

Question 50

What side of the building are smoke ejectors usually set up

Answer 50

Leeward side.

Question 51

Churning, or recirculating of fire gasses around a smoke ejector, can be prevented by

Answer 51

Hanging a salvage cover around the fan and open space of the opening.

Question 52

How far back are ppv blowers typically set up

Answer 52

6 feet back from opening so it can cover the entire opening

Question 53

How many blowers are usually sufficient for pressurizing a building

Answer 53

One

Question 54

For larger structures how many ppv should be used if needed

Answer 54

Two in tandem, (one behind the other)

Question 55

Compared to mechanical smoke ejectors, fog streams can move how much more smoke volume

Answer 55

2-4 times more depending on type, gpm and position of streams

Question 56

For hydraulically venting a fog stream should be placed how

Answer 56

With a 60* pattern covering 85-90% of the opening. Appx 2’ away from window.

Question 57

A spray pattern for a fog nozzle hydraulically venting should not exceed 60* because

Answer 57

It looses efficiency the wider it gets.

Question 58

Disadvantages to hydraulically venting

Answer 58

Increased water damage
Drain on water supply
Icy conditions inside and out when cold
Nozzle operator remains in hostile environment
May have to be interrupted if Scba goes empty

Question 59

For horizontal venting to be effective, a proper balance between volume of air introduced and what must be maintained

Answer 59

Balance between volume introduced and size of exit openings

Question 60

Contents of building can be improperly positioned or stacked in hallways and near openings, causing what

Answer 60

Disturbance of ventilation

Question 61

If the fire is on the windward side, ppv doesn’t counteract the wind because wind velocity is too high, and vertical venting is impractical. Ventilation should

Answer 61

Be delayed until the fire is under control, ff must be alert for sudden fire behavior changes however.

Question 62

Horizontally venting fire can spread into an attic through

Answer 62

Eave vents