TRAINING BULLETIN September 1, 2010 PURPLE K DRY CHEMICAL EXTINGUISHER 1. INTRODUCTION

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1 TRAINING BULLETIN September 1, INTRODUCTION Purple K dry chemical extinguishers have been issued to various units of the department. Purple K is a potassium bicarbonate base dry chemical. While other dry chemical extinguishers are effective, Purple K has demonstrated a superior extinguishing capability in combating methanol fires. Methanol's use as an alternate fuel for gasoline and diesel powered vehicles and equipment throughout the city will inevitably lead to fire situations at which the extinguishment of this fuel will be required. Purple K is also effective on gasoline, diesel and compressed gas fires. 2. HAND HELD EXTINGUISHER 2.1 DESCRIPTION Cylinder of heavy gauge steel welded construction having an internal corrosion resistant coating Nozzle - High velocity Height 23 3/4", weight 52 lbs. (27 lbs. of which is dry chemical). 2.2 FEATURES Purple K Dry Chemical Capacity of 27 lbs Discharge Range 19' - 20' Discharge Time - 11 seconds Coverage approximately - 30 square feet Temperature restrictions - extinguisher can be used between minus 40 and 120 degrees. 1

2 2.3 OPERATION Remove ring pin and hose Squeeze handle Direct stream at base of flames using a side to side motion. In order to achieve even distribution, and to obtain best results the nozzle should be held with the member's strongest hand. Hold the extinguisher upright Expended extinguishers can be exchanged by attaching an RT-2 and forwarding to Technical Services for replacement. 2.4 INSPECTION The extinguisher shall be checked at the beginning of each tour and thoroughly examined once a month Inspection at the beginning of each tour is to include: A. Ensuring the extinguisher is in its designated place and is accessible for immediate use. B. Examining the extinguisher shell for evidence of physical damage, corrosion or other impairments. C. If extinguisher is defective for any reason, attach an RT-2 and forward to Technical Services for replacement. 3. WHEELED EXTINGUISHER UNITS Three-hundred pound dry chemical wheeled units are used extensively in industrial complexes throughout the city of New York. Familiarization with these units is important. Note that these units are not necessarily Purple K, but may be dry chemical with a sodium bicarbonate base. Sodium bicarbonate is not as effective on methanol fires as Purple K. It will be necessary to determine, before use, what type of dry chemical the wheeled unit contains. 3.1 DESCRIPTION A high-capacity steel tank containing dry chemical extinguishing agent Activated by separate nitrogen cylinder Extinguishing agent is propelled through hose and released at spray nozzle Entire apparatus rests on wheeled support. 2

3 3.2 OPERATION Stretch entire amount of hose from unit, approximately 100 ft Charge unit by opening valve on nitrogen cylinder Open nozzle until flow of dry chemical is noted Close nozzle and move to the point of operation. Note: Hose, whether on wheeled units or on reels found on dry chemical trucks should be stretched before charging to eliminate the binding of the hose to the reel. Pressurization of the hose will cause the hose to expand and possibly bind on the reel. 3

4 4. APPLICATION TECHNIQUES 4.1 FLAMMABLE LIQUID SPILL FIRE Approach the fire from the upwind side holding the nozzle at a 45 degree angle to the ground. Stop walking at a point approximately 10 to 12 feet from the front edge of the fire area.(fig. 4-1) Direct the stream of dry chemical 6 inches ahead of the flame edge.(fig. 4-2) Direct the dry chemical stream using a rapid side to side sweeping motion. Each sweep of the dry chemical stream must be slightly wider than the near edge of the fire. Advance slowly, working the fire to the back edge of the spill.(fig. 4-3) Extinguish the small fire at the back edge of the spill aiming directly at the base of the flame. Do not raise the nozzle to chase the "fire ball."(fig. 4-4) 4

5 4.2 FLAMMABLE LIQUID SPILL FIRE WITH OBSTACLE Approach the fire from the upwind side holding the nozzle at a 45 degree angle to the ground. Stop at a point approximately 10 to 12 feet from the front edge of the fire area.(fig. 4-5) Direct both streams of dry chemical 6 inches ahead of the flame edge.(fig. 4-6) Advance slowly around each side of the obstacle. Each operator should cover two-thirds of the fire area using a side to side sweeping motion.(fig. 4-7) Extinguish the fire remaining behind the obstacle by aiming both streams directly at the base of the flame. If the obstacle itself contains burning liquid, the agent should then be directed into the container.(fig. 4-8) 5

6 4.3 FLAMMABLE LIQUID FIRE IN DEPTH Approach the fire from the upwind side holding the nozzle at a 45 degree angle to the ground. Stop at a point approximately 10 to 12 feet from the front edge of the fire area.(fig. 4-9) Direct the dry chemical stream at the upwind corner of the fire, 6 inches ahead of the lip of the fire area. Make a slow pass across the front edge of the area, making sure to overlap each side by 6 inches.(fig. 4-10) Direct the dry chemical stream using a rapid side to side sweeping motion. Each sweep of the dry chemical stream must be slightly wider than the pan.(fig. 4-11) Raise the dry chemical stream slightly but continue to hold the nozzle at a 45 degree angle. This is accomplished by raising the extinguisher. Work the flames to one corner of the area and extinguish. (fig. 4-12) 6

7 4.4 FLAMMABLE LIQUID FIRE IN DEPTH WITH OBSTACLE Approach the fire from the upwind side holding nozzles at a 45 degree angle to the ground. Stop at a point approximately 10 to 12 feet from the front edge of the fire area.(fig. 4-13) Direct both streams of dry chemical 6 inches ahead of the lip of the front edge of the fire area.(fig. 4-14) Advance slowly around each side. Each operator should cover two-thirds of the fire area using a side to side sweeping motion.(fig. 4-15) Extinguish the fire remaining behind the obstacle by aiming both streams directly at the flame. If the obstacle itself contains burning liquid, then the agent should be directed into the container. (fig. 4-16) 7

8 4.5 GRAVITY FED FIRE USING DRY CHEMICAL Approach the fire from the upwind side holding the nozzle at a 45 degree angle to the ground. Take a position at approximately feet from the front edge of the fire area. (fig. 4-17) Extinguish flammable liquid spill fire first using a side to side sweeping motion.(fig. 4-18) Raise dry chemical stream to the bottom of the plate and momentarily hold there.(fig. 4-19) Continue to raise dry chemical stream, extinguishing the fuel source last.(fig. 4-20) 8

9 4.6 THREE DIMENSIONAL GRAVITY FED FIRE Approach the fire holding the nozzle at a 45 degree angle to the ground. Stop at a point 10 to 12 feet from the front edge of the spill fire area.(fig. 4-21) Make a VERY SLOW pass across the front edge of the flammable liquid spill. Be sure the spill is completely extinguished before moving on. DO NOT close extinguisher nozzle.(fig. 4-22) Raise the dry chemical stream to front lip of the dip tank. Extinguish the dip tank fire.(fig. 4-23) Direct the dry chemical stream up the tray pushing the fire towards the fuel source. Extinguish fuel source last.(fig. 4-24) 9

10 4.7 FLAMMABLE LIQUID PRESSURE FIRE Approach the fire from the upwind side. Stop at a position approximately 15 feet from the front edge of the spill fire area.(fig. 4-25) Direct the dry chemical stream at the fuel source.(fig. 4-26) Move the dry chemical down the stream of escaping fuel.(fig. 4-27) Extinguish remaining spill fire using a rapid side to side sweeping motion.(fig. 4-28) Note: In some cases it may not be desirable to extinguish this fire unless the fuel supply can be shut off. 10

11 4.8 FLAMMABLE GAS PRESSURE FIRE Approach the fire from the upwind side. (fig. 4-29) Direct the dry chemical stream at the fuel source.(fig. 4-30) Move the dry chemical up the stream of escaping gas.(fig. 4-31) Continue moving the dry chemical stream upward until the fire ball is extinguished. (fig. 4-32) Note: In some cases it may not be desirable to extinguish this fire unless the fuel supply can be shut off. 11

12 4.9 LIQUEFIED PETROLEUM GAS (LPG) FIRE USING WATER CAUTION: LPG fires should not be extinguished unless immediate fuel shutoff is possible. LPG vapors are heavier than air and can flow downwind considerable distances, possible finding an ignition source and igniting causing a flash fire or explosion. Approach the fire from an upwind position using the wind to best advantage. Open the water nozzles first and adjust to the fog position. (fig. 4-33) The dry chemical operator should then open the dry chemical nozzle and direct the stream at the fuel source (broken flange).(fig. 4-34) If a spill fire is present, move the dry chemical down the stream of escaping fuel to the ground spill, and with a side to side sweeping motion extinguish the spill fire.(fig. 4-35) Continue to cool the piping and surrounding area with water. Close supply valve to stop fuel flow. Dry chemical operator should stand by in case of reflash.(fig. 36) Note: The simultaneous use of water and dry chemical combine to make a highly effective fire fighting tool. While the water acts as a coolant and heat shield, the dry chemical provides the means for rapid extinguishment. 12

13 5. CONCLUSION: In order to maintain our effectiveness in the fire service we must be aware of the changing technology evolving in today's society. Alternate type fuels may become the norm in the near future. The Purple K extinguisher and the dry chemical wheeled unit will help us remain in step with the fast changing technology. However, like most equipment, it is only as effective as people using it. Through drills and practical use each member can become proficient in the use of this equipment. 13