Chapter 14 Ventilation Principles

Question 1

Define ventilation as pertains to firefighting operations.

Answer 1

Procedures necessary to effect the redirection and removal of fire elements from a structure

Question 2

At what temperature can fire gases and smoke from modern synthetic materials readily ignite?

Answer 2

800 degrees to 900 degrees F

Question 3

What is the most popular form of ventilation?

Answer 3

Horizontal ventilation due to ease and safety of implementation

Question 4

Define mushrooming.

Answer 4

When the by-products of combustion reach the highest level possible, they bank downward, creating a dangerous environment for suppression personnel

Question 5

Which fireground hazard, backdraft or flashover, is more common on the modern fireground?

Answer 5

Flashover

Question 6

Name three primary factors that can be used to evaluate a contaminated environment.

Answer 6

Is there smoke with or without heat?

Is there acceptable visibility?

Are conditions improving or not improving?

Question 7

What three primary dangers are commonly associated with basement fires?

Answer 7

Weakened floor directly above a basement fire, vertical extension, and safe access to the seat of the fire

Question 8

What portion of a room is minimally affected by horizontal ventilation?

Answer 8

The upper portions of a room

Question 9

What primary consideration will set the parameters for ventilation in a multistory private dwelling?

Answer 9

The location of the fire

Question 10

What portion of a multistory building will be ventilated by opening a penthouse or bulkhead door?

Answer 10

Primarily, that stair shaft and the hallways that open to it

Question 11

What two categories can our knowledge of ventilation be divided into?

Answer 11

Theoretical

Experiental

Question 12

When the supply of oxygen is reduced below 21 percent, the production of what gases are accelerated?

Answer 12

formaldehyde, carbon monoxide, acrolein, sulfur dioxide, ammonia, hydrogen cyanide, hydrogen chloride, chlorine, osides of nitrogen, phosgene, isocyanates

Question 13

What is the primary culprit in fire fatalities as a result of exposure to toxic atmospheres?

Answer 13

Carbon monoxide

Question 14

Wood products produce ___ BTUs, polyurethane products produce ____ BTUs, polystyrene produces produce____ BTUs

Answer 14

7,000
12,000
18,000

Question 15

How much fire loss is directly the result of fire?

Answer 15

Less than half

Question 16

When does backdraft occur?

Answer 16

When oxygen is introduced into a confined area that is pressurized with heated, oxygen-deprived, flammable gases, resulting in an explosion

Question 17

What is the first phase of fire?

Answer 17

A free-burning fire in a confined building initially has the proper ratio of fuel, heat, and oxygen

Question 18

What happnens during the 2nd phase of a fire?

Answer 18

Oxygen is reduced, and temperatures, smoke, and cabon monoxide are increased. Oxygen drops to about 17 percent, and temps can hit 1300 degrees

Question 19

What happens during the 3rd phase of a fire?

Answer 19

Oxygen levels drop (13-15 percent), temps and CO continue to increase. fire smolders

Question 20

During the 3rd phase of a fire, how much can the expansion of gases and smoke increase?

Answer 20

Factor of 3

Question 21

What are several distinct trademarks of potential backdraft?

Answer 21

Heavy dark smoke issuing under pressure. turbulent, boiling..
Smoke changing directions or drawn back into structure, sometimes with a whistle

Question 22

What is the best way to eliminate backdraft?

Answer 22

vertical ventilation

Question 23

What is Flashover?

Answer 23

The sudden ignition of exposed combustible surfaces or gases in an involved area

Question 24

What are the differences between flashover and backdraft?

Answer 24

Flashover lacks:

1. the sudden introduction of oxygen to a depleted atmosphere
2. confinement
3. heated flammable gases under pressure

Question 25

Flashover can drop the oxygen content in a room from 21 percent to what?

Answer 25

4 percent

Question 26

During flashover, carbon monoxide levels can reach what?

Answer 26

40,000 ppm

Question 27

Temperatures during flashover can reach what temp at the ceiling?

Answer 27

1800 degrees F

Question 28

Why can a flashover be more dangerous than a backdraft?

Answer 28

Because of its subtler warning signs

Question 29

Where are the prime locations of fires in institutions?

Answer 29

Kitchens, lounges, and storage areas

Question 30

What should be the initial consideration when faced with a fire in a public assembly building?

Answer 30

it should focus on ventiliation operations that will best assist their evacuation

Question 31

When can you use the HVAC system to ventilate?

Answer 31

only when it has been determined that the fire has been controlled

Question 32

When can banked elevators be used?

Answer 32

When they terminate at least 5 floors below the reported fire