15 - Fire attack

Question 1

Direct attack

Answer 1

Fire stream applied directly on the burning fuel, cooling fuels and therefore stopping further pyrolysis.
Can be performed when streams can reach the seat of the fire. Steam will be produced, reducing visibility

Question 2

Indirect attack

Answer 2

Applying water to a heated compartment from the exterior of the compartment (inside or outside the building). Uses water to steam covversion to absorb heat.

Question 3

Interior indirect attack techniques

Answer 3

Shooting straight stream through thermal layering to prevent breaking it up, then banking off walls and ceiling to break the stream and aid with cooling the environment.

Question 4

Combination attack

Answer 4

Hitting a structure from the outside to rapidly cool the interior until proper ventilation can be established and interior fire attack can begin. Bank a straight stream off ceilings or windows sills to break the stream.

Question 5

Transitional attack with a handline

Answer 5

Spray the interior without moving.
If already inside, spray compartments in short bursts, then closing the door to allow cooling. Repeat as nessisary.
Once gases are cooled, apply stream directly to fuels

Question 6

Reading smoke

Answer 6

Velocity: How fast smoke moves away from base of fire, main indicator of impending flashover.
Volume: How much fuel has off gassed within a container.
Density: How much unburnt fuel remains. Thicker means more hostile fire.
Color: determines possible fuel sources and fire stage.

Question 7

Smoke Volume vs Density

Answer 7

Volume: Amount of fuel already burnt, representing the scale of the event. Layering.

Density: Amount of unburnt fuel, representing the POTENTIAL of the event. Thicker smoke is more hostile.

Question 8

Smoke colors

Answer 8

White - Steam
Grey - Plastic
Tan/Brown - Unfinished wood pyrolizing just prior to ignition. Eatly warning sign for structural collapse.
Black - Any material heated to its fullest.

Question 9

Black fire

Answer 9

HIgh volume, high density, high velocity, black colored smoke. Indicator of impending flashover. AGGRESSIVLY COOL AND BACK OUT.

Question 10

Solid vs straight stream

Answer 10

Solid stream is created with a smooth bore nozzle, allowing for the greatest penetration with as little spray as possible.
Straight stream: Using a fog nozzle, all the droplets are packed tightly, allowing for good penetration but more heat absorbtion.

Question 11

Solid stream adv and disadv

Answer 11

Adv: greater visiblity, range, penetration. Reduced nozzle pressure, Less layer disruption.
Disadv: Cannot be used for foam application, less heat absorbtion, only 1 pattern.

Question 12

Factors effecting water streams

Answer 12

Wind, Gravity, Velocity, Air friction.
Pattern on fog nozzles.

Question 13

Optimal angle for maximum stream reach? for maximum height?

Answer 13

30 to 34 deg. 75deg for max height.

Question 14

Broken streams

Answer 14

Resembles the breakover point of a solid stream, except its already in that form at the end of the nozzle. Allowes for greater penetration and heat absorbtion. Most often used in confined spaces using the piercing nozzle.

Question 15

Causes for defective streams

Answer 15

Insufficiant pressure
Excessive pressure
Defective tip
Air in the line
Kink in the line

Question 16

Indicators a fire stream has been properly applied

Answer 16

Darkening down
Steam generation
Rapid heat fluctuation
Droplets being produced

Question 17

2 types of exposures

Answer 17

Interior: Areas of a building not yet involvled. Can be controlled with coordinated ventilation and door control.
Exterior: Buildings or proerty close to the fire building in danger of becoming involved due to heat transfer.

Question 18

Concerns with garage fires

Answer 18

Fire load and fuel type
Attached vs detached garages
Access
Proximity to exposures

Question 19

Guidlines for vehicle fire attack

Answer 19

Approch from upwind and uphill, at 45 degrees to the vehicle.
Establish scene safety, directing traffic away, maintain awarness of oncoming traffic.
Extinguish fire near occupants first.
Ensure adegqute water supply.
Consider possibility of using foam.
Consider use of piercing nozzle for hood unaccessible compartments.