TB 90 - Fire Burns

Question 1

Steam can cause full thickness burns to unprotected skin with less than _____ seconds exposure

Answer 1

three seconds

Question 2

A major cause of burns to firefighters is the disruption of the THERMAL LAYER by the use of _________.

Answer 2

high flow spray nozzles… this causes superheated steam being pushed down to a FF’s level.

(This is considered a CONVECTIVE heat source)

Question 3

A Firefighter caught in a flashover, just ____ feet inside a room, will be exposed to temperatures of 1,000 to 1,500F, and direct flame impingement for at least ____ seconds.

Answer 3

5 ft

2 sec

Question 4

The six observable or measurable factors in a Class “A” fire are:

Answer 4

1. Input heat
2. Fuel
3. Oxygen
4. Proportioning of the fuel/air mixture
5. Mixing of the fuel/air mixture
6. Uninhibited chain reactions between active fuel/air molecules

Question 5

BTU or British Thermal Unit is a basic UNIT OF HEAT.

A BTU is the amount of heat required to raise the temperature of ONE _____ of water _____ degree fahrenheit.

Answer 5

Pound

one

Question 6

_______ is the THERMAL CAPACITY of a substance. It is the number of BTU’s required to raise the temperature of one pound of a substance one degree fahrenheit

Answer 6

Specific Heat

(the specific heat of WATER is ONE BTU).

Question 7

Heat is transferred in what three ways?

Answer 7

1. Radiation - transmitted similar to LIGHT WAVES
2. Convection - heat through motion of a heated FLUID
3. Conduction - transfer of heat through MATTER

Question 8

What is the primary HEAT TRANSFER method within structures and is responsible for the majority of fire and SMOKE SPREAD within structures?

Answer 8

Convection

Question 9

Fire extension through CONDUCTION occurs only in RARE CIRCUMSTANCES, but still must be considered at many fires.

The primary consideration relative to CONDUCTIVE heat transfer is __________.

Answer 9

-structural integrity

(The transfer of heat from metal connectors to wooden structural members, weakening those connections, is a major cause of structural collapse, particularly involving any type of truss construction.)

Question 10

HEAT is the MOST DANGEROUS and threatening PRODUCT of COMBUSTION for the following reasons:

Answer 10

1. Products of combustion are carried vertically and horizontally (MUSHROOMING) to remote areas of the structure.
2. Through convection and radiation new fuel sources are heated to their ignition temperatures and contribute to rapid fire spread and extreme fire behavior.
3. Metal to wood structural connections weaken.

Question 11

Fire Progress and Development in the GROWTH STAGE

The rate of combustion, fire intensity, and the total combustion product output are governed by SIX major factors:

Answer 11

1. The AMOUNT of exposed combustible surface.
2. The ARRANGEMENT of the combustible surfaces.
3. The TYPE of fuel source.
4. The NATURE of the combustible surfaces.
5. The RATIO of combustible surface to room or area volume. (PRIMARY FACTOR that determines the time to Flashover)
6. The amount of available AIR flow or ventilation.

Question 12

Fire Progress and Development

The PRIMARY FACTOR that determines the time to Flashover or full room involvement, assuming that there is adequate air supply is?

Answer 12

The RATIO of combustibles to room or area volume

Question 13

Fire Progress and Development

Growth Stage- The rate of sustained combustion is largely determined by available ________.

Answer 13

ventilation or air flow.

Question 14

Fire Progress and Development

The fully developed stage can be identified by the ________ (upward/horizontal/downward?) portion of the fire curve.

Answer 14

horizontal

Question 15

What are the stages in the development of a fire?

Answer 15

-Growth Stage

-Fully Developed Stage

-Decay Stage

Question 16

What three flash phenomena can occur in a superheated, smoke filled environment, which can trap and kill Firefighters?

Answer 16

1. Roll over - flame MIXED with smoke at ceiling lvl JUST BEFORE flashover occurs.
2. Flashover - takes place after rollover at the END of the GROWTH STAGE of fire
3. Flame over - after flashover, rapid flame spread over one or more surfaces

Question 17

Flash Phenomena

What is the last warning sign that flashover is about to occur?

Answer 17

Roll over

Question 18

What is the most deadly flash phenomena?

Answer 18

-Flashover

(Particular danger to first-in FFs conducting INITIAL ATTACK and search WITHOUT proper VENTILATION and BACK-UP)

Question 19

Warning Signs of Flashover:

Answer 19

-A fire burning within a room or area that is producing a buildup of heated smoke at the UPPER levels of the structure.

-Smoke that is increasing in heat and density.

-A rapid banking down of HEATED SMOKE.

-Fire of significant intensity exposing contents and surrounding areas to radiant and/or convective heat.

-ROLL OVER occurring. Flame visible in the smoke rolling out the tops of open doors or windows, and/or flames rolling in the upper ceiling level inside the fire area.

Question 20

When operating inside, watch for the following warning signs of a smoke explosion:

Answer 20

-Sickly or intermittent flame due to a reduced oxygen level.

-Smoke being drawn past you into the fire area of the structure.

-Heavy smoke SWIRLING with GREAT FORCE.

-Flickering FLAMES in the SMOKE above you as heavier combustion products suspended in the superheated atmosphere try to ignite.

Question 21

A true backdraft is extremely rare.

Oxygen content must fall to between _____% and _____%. Explosive products of combustion are 1,000F to 1,800F and higher. They have mushroomed and pressurized the entire structure.

The process only needs what to produce a backdraft?

Answer 21

11 and 15%

Air

Question 22

Warning Signs of Backdraft:

Answer 22

-Smoke ISSUING OUT of any available STRUCTURAL OPENINGS.

-Smoke IGNITING when it rolls into the outside air.

-Heavy, hot smoke is visible but no fire can be seen or heard.

-Structure appears to be breathing or puffing smoke.

-Windows DARKENED due to long exposure to heat, may look like mirrored glass from the outside.

-CONDENSATION forming on windows.

-Windows pulsating or rattling from internal pressure.

-Large plate glass windows may bulge from heat and internal pressure.

Question 23

What is the primary difference between Flashover and Backdraft?

Answer 23

The amount of air present

Question 24

What is the “triggering event” for:

1. Flashover?
2. Backdraft?

Answer 24

1. Addition of HEAT
2. Addition of OXYGEN

Question 25

A backdraft occurs during what stage of a fire?

Answer 25

Smoldering/Decay stage

Question 26

_________ signals the beginning of the structural collapse danger of a fire.

Answer 26

Flashover

(Before flashover occurs the fire generally is fueled only by the contents of the room or area)

Question 27

What are four construction features that present the greatest danger to Firefighters from collapse?

Answer 27

1. Any type of TRUSS construction
2. UNREINFORCED masonry construction
3. Any CANTILEVER construction
4. UNPROTECTED steel construction

Question 28

Officers….

Maintain coordination and unity of purpose. Strategy, tactics, and _______ must fit the situational needs.

Answer 28

operational timing

Question 29

Flashover can be identified as the portion of the fire curve occurring?

Answer 29

NEAR THE END of the growth stage.

(This marks the beginning of the fully developed stage.)

Question 30

One of the greatest risks Firefighters encounter during Firefighting operations is thermal burns.

These can occur in one or more of the following ways:

Answer 30

1.Contact with conducted heat sources
2. Exposure to convective heat sources
3. Exposure to radiant heat sources
4. Exposure to direct flame impingement (MOST SEVERE)

Question 31

__________ is one of the major causes of fire ground fatalities. It is the most dangerous STAGE of FIRE DEVELOPEMENT.

Answer 31

Flashover

(The TECHNOLOGY and ATTITUDES of today are in many ways MAJOR contributing factors.)

Question 32

Firefighter survival begins with __________.

Answer 32

-pre-fire planning

-preparation

-training

Question 33

_________ is the quantity of heat ABSORBED by a substance when passing between PHASES.

Answer 33

Latent Heat

(Solid to liquid is the latent heat of FUSION. Liquid to vapor is the latent heat of VAPORIZATION.)

Question 34

________ is a WARNING of a more deadly EVENT to follow.

Answer 34

Roll Over

(Roll over occurs BEFORE flashover in the GROWTH stage of a fire)

Question 35

When inside, staying low and working the nozzle in the upper atmosphere will affect cooling and push back ROLLOVER.

Controlling the FORM and FLOW of water will ____________.

Answer 35

maintain THERMAL BALANCE and PREVENT excessive STEAM production.

Question 36

__________ is a sudden full room or area involvement in flame, or the sudden auto ignition of combustible surfaces and/or gases in an area heated by CONVECTION and/or RADIATION, resulting in a SUDDEN and INTENSE RISE in TEMPERATURE.

Answer 36

Flashover

Question 37

If vertical ventilation is required, provide a MINIMUM of TWO ladders to every structure and ONE ADDITIONAL ladder for every ______ member team on the roof.

Answer 37

Two

Question 38

Our ability to initiate and carry out sound tactics, standard procedures, and operations on the fire ground will dictate our __________, which are the KEYS to SAFETY

Answer 38

-actions
-position
-timing