TB 11 Dry Chemical Fire Extinguisher

Question 1

TB 11 Dry Chemical Fire Extinguisher

The chemical itself is baking soda (sodium bicarbonate, NaHCO 2 ) especially treated to make it resistant to caking and moisture, and capable of being readily dispersedinto a fire-killing cloud.

Answer 1

reference

Question 2

TB 11 Dry Chemical Fire Extinguisher

Generally dry chemical is most effective on fires involving flammable liquids, gases, and liquefied gases.

It is the fastest and most spectacular extinguishing material for spilled fuel areas. Dry chemical is effective on fires involving deep-layer flammable liquids, natural gas leaks, and liquefied flammable gas leaks and spills. More specifically, dry chemical is effective on fires involving dip tanks, ruptured tank cars, broken gas lines, broken valves or flanges on liquefied flammable gas cylinders, and breaks and leaks in pipes and tubing for flammable gases, anesthetics, etc * it will extinguish fires involving bottled gases even when they are burning under high pressure.

Answer 2

reference

Question 3

TB 11 Dry Chem

shell of heavy gauge steel, tested to ____ psi

Answer 3

600

Question 4

TB 11 Dry Chemical Fire Extinguisher

There has been an increasing use of dry chemical on Class A fires, especially in textile fibers such as cotton. However, it serves primarily to obtain very rapid control of the fire. The surface flames are almost immediately extinguished, but the Class A material will usually still smolder. It is desirable to have water available for final extinguishment; although larger quantities of dry chemical may be used for complete extinguishment in some instances when water is not available.

Answer 4

reference

Question 5

TB 11 Dry Chem

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

The extinguisher will function effectively only so long
as the air pressure is between ___ to ___ psi.

Answer 5

twenty (20)

165

125 to 175

Question 6

TB 11 Dry Chemical Fire Extinguisher

It is ineffective on metal fires such as magnesium and sodium.

Answer 6

reference

Question 7

The extinguisher has an effective range of approximately ___ to ___ feet. 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 ___ to ___ feet.

Answer 7

15 to 20

6 to 8

Question 8

TB 11 Dry Chem

This extinguisher has a rating of 20-B,C, meaning that in the hands of an average operator it is capable of extinguishing a 20 square foot deep-layer Class B fire, and is safe for use on fires involving energized electrical equipment.

Answer 8

reference

Question 9

TB 11 Dry Chemical Fire Extinguisher

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

Answer 9

reference

Question 10

TB 11 Dry Chemical Fire Extinguisher

The dry chemical in these extinguishers can also be used to neutralize acid spills. 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 10

2 or 3

Question 11

TB 11 Dry Chemical Fire Extinguisher

nozzle which shapes the dry chemical into a ___ degree fan stream

Answer 11

60