TB 11 Pressurized Dry Chem Extinguisher

Question 1

The chemical itself is…

Answer 1

baking soda (sodium bicarbonate, NaHCO 2 )

Question 2

It is treated to make it resistant to___ and ____.

Answer 2

Caking & Moisture

Question 3

HOW IT WORKS:

Dry Chemical, in the presence of heat, releases ________and _______vapor which provides a “smothering action”

Answer 3

Carbon dioxide & Water vapor

Question 4

HOW IT WORKS:

Heat is absorbed by both the solid particles and water vapor which provides ______

Answer 4

Cooling

Question 5

Dry chemical is most effective on fires involving

Answer 5

flammable liquids
Flammable gases
liquefied gases.

Question 6

Dry Chem is the fastest and most spectacular extinguishing material for …

Answer 6

Spilled fuel areas

Question 7

Dry chemical is approximately ____as effective as CO2 on hydrocarbon fires, including______.

Answer 7

Twice, Methane

Question 8

Dry Chem car fire technique should not be used unless at least ______firemen are presen

Answer 8

Two; 1 for rescue and 1 to provide protective cover.

Question 9

When an acid spill is encountered, pull the locking pin, hold the nozzle ___or ___feet above the acid, squeeze the valve just enough to allow the powder to flow gently from the nozzle and spread the powder over the surface of the acid.

Answer 9

2 or 3 ft

Question 10

When fires are encountered involving leaks of gases, especially those “heavier than air“ such as ________ & _______the fire ordinarily should not be extinguished until control of the gas can be obtained,

Answer 10

Butane & Propane

Question 11

dry chemical, such as is used in LAFD portable extinguishers, causes ____________of “foam blankets”when used in conjunction with ________ foam.

Answer 11

rapid breakdown and collapse

Mechanical Foam

Question 12

Dry Chem is ineffective on metal fires such as __________and _________

Answer 12

Magnesium & Sodium

Question 13

Because of its dielectric characteristics, dry powder can be used safely’ on ?

Answer 13

Electrical Fires

Question 14

Shell tank of Dry Chem extinguishers are tested to _____ psi

Answer 14

600

Question 15

The nozzle of extinguishers shape the dry chem into a __ degree fan stream

Answer 15

60

Question 16

The shell is filled with twenty ___pounds of dry chemical and then pressurized to approximately _____ psi with compressed air.

Answer 16

20 lbs

165 psi

Question 17

This extinguisher has a rating of _______
meaning that in the hands of an average operator it is capable of extinguishing a ____square foot deep-layer Class B fire, and is safe for use on fires involving energized electrical equipment.

Answer 17

20-B,C rating

20 sq ft

Question 18

discharge time of a 20- pound dry chemical extinguisher with the valve fully open is…

Answer 18

10 seconds

Question 19

The 20 pound CO 2 extinguisher in use on the Department will last…

Answer 19

60 seconds

Question 20

Dry Chem extinguisher has an effective range of approximately…

Answer 20

15 to 20 feet

Question 21

To prevent splashing when using on depths of flammable liquid, care should be taken to direct the initial discharge from a distance not closer than…

Answer 21

6 to 8 feet

Question 22

Dry Chem should be checked ____ should be checked…

Answer 22

DAILY

Question 23

Dry chems full charge is b/w ____-_____

Answer 23

125-175psi

Question 24

___________ remove the extinguisher from the rack, invert it, and shake to preclude any possibility of the chemical caking.

Answer 24

Once each Month

Question 25

Tag the extinguisher with a _______and send it to the shops, whenever it needs to be recharged with air or dry chemical.

Answer 25

F-175