Asia Risk Information <2014 No.4>

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1 No Asia Risk Information <2014 No.4> Selection, Management and Use of Portable Fire Extinguishers Various disaster countermeasures are taken in offices and factories to prevent fire in workplace. However, in case of fire, especially in Southeast Asia where sprinkler system is not widely used comparing to Europe and the United States, it is important to initiate initial fire fighting promptly to minimize damages. Japanese standard for the installation of fire extinguishers stipulates that portable fire extinguishers must be selected based on the occupancy hazard and total building area. It requires fire extinguishers should be installed within 20 meters from fire risk (any room or area). Fire classifications and capacity of fire extinguishers may be slightly different in different countries. However, the travel distance to a fire extinguisher should be 5-30 meters from fire risk. [Table.1] Travel Distance to Portable Fire Extinguishers Fires in ordinary combustible Fires in flammable liquids etc. (*6) materials (*5) Japanese Standard (*1) 20m American Standard(*2) 75ft (Approx. 23m) 30-50ft (Approx. 9-15m) (*7) Singapore Standard (*3) 15m 5-15m (*7) Malaysian Standard (*4) 30m 10-30m (*7) (*1)Fire Service Act (Article 6-6) (*2)NFPA 10 Standard for Portable Extinguishers (*3)Singapore Standard SS578 : 2012 Use and Maintenance of Portable Fire Extinguishers (*4)Malaysian Standard MS1539 Specification for Portable Fire Extinguishers (*5)Equivalent to Class A in Japanese Standard, or Class A Fire in NFPA standard (*6) Equivalent to Class B in Japanese Standard, or Class B Fire in NFPA standard (*7)Travel distance may vary depending on the hazard level of the fire class and the type of fire extinguisher to be installed. Most Southeast Asia countries have established their standards for portable fire extinguishers based on the American Standard (NFPA), though there are some exceptions like Malaysia, where they established the standard based on British Standard and Singapore where they follow both NFPA (installation standard) and British Standard (fire classifications). Followings are four items important for prompt and effective initial fire fighting. 1. Identification of fire risk: To identify the fire risk 2. Selection of suitable fire extinguisher: To select suitable fire extinguisher for the identified fire risk 3. Appropriate management: To conduct daily inspection to maintain portable fire extinguishers in a good condition 4. Proper use of fire extinguishers: To ensure that portable fire extinguishers are used properly 1. Selection of Portable Fire Extinguishers The selection of portable fire extinguishers should be carefully considered as there are many different types of extinguishing agents available, with its unique advantages and disadvantages. Therefore, it is necessary to understand fire risk in the protected area and advantages/disadvantages of the extinguishing agents. 1

2 1-1. Fire Classifications Portable fire extinguishers are selected for the specific classes of fires. According to Japanese Fire Service Act, there are three types of fire classes as follows. [Table.2] Fire Classes in Japanese Fire Service Act Classification Description of Fire Class A (Fire involving Fires involving mainly solids (e.g. paper, wood, textile, resin) ordinary combustibles) Class B (Fires involving Fires involving gasoline, kerosene and grease etc. flammable liquids) Class C (Fires involving Fires involving electric equipment etc. electric equipment) Many of Southeast Asian countries follow NFPA10 (NFPA: Standard for Portable Fire Extinguishers). The table below shows the fire classifications stipulated in the standard. [Table.3] NFPA Classifications of Fires Classification Description of Fire Class A Fires in ordinary combustible materials, such as wood, paper and cloth Class B Fires in flammable liquids, combustible liquids, solvents, and flammable gases etc. Class C Fires that involve energized electrical equipment Class D Fires in combustible metals Class K Fires in cooking appliances that involve combustible cooking media (vegetable or animal oils and fats) Please note that portable fire extinguishers should be installed carefully in Singapore (*) and Malaysia because they adopt the classification in British Standard, which is slightly different from that in NFPA. (*) Fire classification in Singapore Standard was similar to the NFPA fire classification until However, after the revision of the law in 2012, it is in line with British Standard. [Table.4] Fire Classification in Singapore and Malaysia Standards Classification Description of Fire Class A Fires in ordinary combustible materials like wood, paper and cloth etc. Class B Fires in flammable liquids, combustible liquids and solvent etc. Class C Fire in flammable gases Class D Fires in combustible metals Class E (*) Fires in live electrical equipment Class F Fires in cooking appliances that involve combustible cooking media (vegetable or animal oils and fats) (*) British Standard does not define a separate fire classification for fires involving energized electrical equipment. 2

3 1-2. Classifications of Portable fire extinguisher [Table. 5] Types of Portable Fire Extinguishers (Extinguishing agents, Methods, Fire Class ification) Method Fire Classification Extinguishing agent (Japanese standard) Cooling Smothering Inhibition Class Class Class A B C Water Jet type Spray Water/Foam Loaded Jet type stream Spray Foam Gas Carbon Dioxide (CO 2) Halogenated agent Dry chemical Soda acid Phosphate [Methods] Cooling: Extinguish fire by removing heat by cooling the burning object Smothering: Extinguish fire by cutting off the oxygen supply to the burning object. Caution is required as it will reignite if oxygen is supplied. Inhibition: Extinguish fire by interrupting the flame-producing chemical reaction. [Fire Classification (Japanese Fire Service Act)] Class A: Water fire extinguisher/loaded stream fire extinguisher/dry chemical fire extinguisher is used to extinguish Class A fires by cooling or smothering. Class B: Loaded stream fire extinguisher/dry chemical fire extinguisher is used to inhibit/smother Class B fires. Use of water fire extinguisher for Class B fires may result in a steam explosion and cause burning oil to spread because water and oil are never mixed. Class C: Gas fire extinguisher/dry chemical fire extinguisher is used to smother/inhibit Class C fires. Use of water fire extinguisher for Class C fire may cause more damage to live electrical equipment by electrical leakage. Dry chemical fire extinguishers can be used for Class C fires. However, residue may cause damage to electrical equipment and longer time for restoration. Thus, for critical equipment, it is recommended to use a fire extinguisher using inert gas (e.g. CO 2 ). However, inert gas should be used carefully as it smothers fire by removing oxygen, which may create a health hazard. Also, it is necessary to ensure that the fire is completely extinguished before ventilating the area/room as it may reignite if oxygen is supplied. 3

4 [Type of Major Fire Extinguishers (Extinguishing Agents)] Water fire extinguishers Water fire extinguishers are extinguishers using pure water or a combination of water and compressed air as extinguishing agent. Water fire extinguishers have good cooling, soaking and penetrating effect. Thus, they are suitable for Class A fires. However, it is not suitable for Class B fires, as water in the agent will flash boil and cause burning oil to spread all over. Similarly, jet type water fire extinguishers are not suitable for Class C fires because there is some concern for electrocution. However, spray type water fire extinguishers are effective on fire in cleanrooms in the semiconductor industry where electrical equipment is totally clean. Mechanical Foam Fire Extinguishers Mechanical foam fire extinguishers use foam solution and force out the extinguishing agent by entraining air with their special nozzles which create mechanical foam. Then, they form a layer of foam over the burning surface (oil) and effectively smother and cool down the fire. They have good cooling, soaking and penetrating effects and prevent re-ignition. However, it is less effective for fire involving hydrophilic materials (e.g. alcohol, acetone) which act as deformer. Meantime, it is not suitable for high-voltage electric equipment as it poses a risk of electrocution. Loaded Stream Fire Extinguisher Loaded stream fire extinguishers use high alkali potassium carbonate solution. They can put out fire more effectively than ordinary water fire extinguishers and suitable for fires involving oil and grease as it interrupts combustion of oil/grease. They have good cooling, soaking and penetrating effects and prevent re-ignition. However, it is not suitable for fires involving electrical equipment because it may cause fault in electrical equipment or electrical leakage. CO 2 Fire Extinguisher CO 2 fire extinguishers use carbon dioxide as an agent and extinguish fire by smothering. They are suitable for Class B fires, fires involving flammable liquids/gases and Class C fires. The agent does not leave residue after use. For that reason, it is advantageous for protection in electrical room etc., where residue causes further damage to electrical equipment. However, they are not recommended for outdoors with high airflow since the agent can rapidly dissipate. Also, it is necessary to pay extra caution after containing fire as fire is likely reignite if it is not extinguished completely. Therefore, it is not suitable for Class A fires. Meantime, they should be used carefully because they extinguish fire by smothering, which may pose a life hazard. ABC Dry Chemical Fire Extinguisher This type of fire extinguishers is multi-purpose fire extinguishers using agent consisting mainly of ammonium phosphate. They are suitable for Class A, B and C fires. Dry chemical is discharged at the burning material to cut off oxygen supply to extinguish fire. It is most widely used as it can extinguish Class A, B and C fires. However, they have poor penetrating effect. If the burning material has absorbed the heat of fire to its core part, it may re-ignite after extinguished. Use of this type of fire extinguishers indoors may cause poor visibility and obstruct evacuation. 4

5 2. Installation and Maintenance of Fire Extinguishers 2-1. Installation of Fire Extinguishers According to Japanese installation standard, ratings of fire extinguishers should be determined based on the occupancy hazard and total building area. The maximum travel distance from a fire extinguisher to fire risk should be less than 20 meters. Fire classifications and fire extinguisher rating may be slightly different in different countries. However, the travel distance from a fire extinguisher to fire risk (any room or area) is in the range of 5-30 meters. Followings are requirements common in most countries. Fire extinguishers shall be located conspicuously without obstruction so that they are readily accessible and immediately available in the event of fire. For effective fire fighting, they should be provided on corridors leading to (emergency) exits. It is recommended to display location remarks to indicate installation points in large factory buildings and locations where visibility is poor. Arrow signs, lamps, signs hung from above, (color) sign boards and banners on the walls and pillars etc. are used to indicate the designated locations of fire extinguishers. Color cording should be applied for easy identification of installation points. Fire extinguisher shall be installed securely on a hanger (intended for the extinguisher), in the bracket (supplied by the extinguisher manufacturer), or in cabinets. It is also important to install fire extinguishers so that the top of the fire extinguisher is not higher than 1.5m above the floor so that personnel can use them easily Maintenance of Portable Fire Extinguisher It is important to conduct regular inspection and maintenance of fire extinguishers so that they are in a good condition for use all the time. In addition to hydrostatic testing, it is recommended to conduct appearance inspection of fire extinguishers by employees. Followings are items of daily inspection. [Table.6] Items for appearance inspection of fire extinguishers Check items Methods Cylinder Damaged cylinder (Deformed, physically damaged, corroded), leakage Safety pin Check for missing, deformed or broken safety pin Puncture lever Deformed, physically damaged Fill cap Deformed/ physically damaged Check for open cap Deformed, damaged, deteriorated Nozzle Connection with hose Clogged Deformed, damaged, deteriorated Hose Connection with nozzle Clogged Pressure indicator Deformed, damaged, deteriorated Pressure gauge reading is within the green zone Generally, commercial fire extinguishers can be used 8-10 years. However, it may expire earlier depending on where and how they are installed. Especially in hot and humid Southeast Asia countries, some fire extinguishers exposed to the weather and direct sunlight expire only after 5-8 years. 5

6 Poorly-maintained or expired fire extinguishers cannot extinguish incipient fire effectively and they may pose a risk of injury due to rupture. There are many cases where the corrosion on the bottom of fire extinguisher weakened the cylinder and ruptured when it was activated. In such cases, pressurized gas inside the cylinder caused fire extinguisher to propel like a rocket. Fire extinguishers outdoors and in the environment with corrosive gas should be handled with special caution. 3. How to Use Fire Extinguisher Followings are basic steps on how to use fire extinguisher, PASS. 1 Pull the pin The safety pin releases a locking mechanism and will allow you to discharge the extinguisher. 2 Aim at the base of the fire Aim at the base of fire, not at the flame. 3 Squeeze the lever Release the extinguishing agent in the extinguisher. 4 Sweep from side to side Sweep the nozzle from side to side, moving carefully toward the fire. Once the flames are out, make sure the fire does not start up again. Fig. How to use fire extinguisher As mentioned earlier, effective initial fire fighting can reduce damage by fire. However, fire fighting operation is conducted in a dangerous situation and fire extinguishers should be operated extremely carefully by following procedures below. First Response to Fire Incidents Rescue people in danger but don t put your life in danger. Press the manual call button to activate fire alarm. Shut down machinery and equipment if necessary. If fire is still at early stage (after the above two responses), take up a fire extinguisher and initiate fire fighting. Please note that initial fire fighting in the following situations involves extreme danger and special caution is required. It is dangerous to extinguish fire if you don t know what is burning. For instance, using of water fire extinguisher to fight burning aluminum powder will cause explosion and result in more damages. Please do not fight a fire and wait for the arrival of fire brigade when suitable fire extinguisher is not available. If you don t have adequate equipment to fight a fire, or don t have a correct type or capacity of extinguisher, it is best not to try to fight the fire. The final rule is to always position yourself with an exit or means of escape at your back before you attempt to use fire extinguisher to put out a fire. In case the fire extinguisher malfunctions, or something unexpected happens, you need to be able to get out quickly. So, please remember to always keep an exit at your back. 6

7 [Table.7] Selection of Portable Fire Extinguishers Examples of usage areas Office, Warehouse, Packing Room Chemical Storage, Machine Room, Mixing Room Electric Room, Transformer Room Clean Room, Computer Room Fire Classification (Japanese standard) Class A Class B Class C Class C Suitable fire extinguishers Water fire extinguisher Dry chemical fire extinguisher Dry chemical fire extinguisher CO 2 fire extinguisher Foam fire extinguisher CO 2 fire extinguisher Clean agent fire extinguisher Dry chemical fire extinguisher CO 2 fire extinguisher Clean agent fire extinguisher Pure water fire extinguisher Portable fire extinguishers are designed to cope with fires of limited size (generally maximum as big as ceiling height). Different classes of fire may exist in production process in factory buildings. Thus, it is important to strategically provide best portable fire extinguishers for the risks in each location. Also, it is critical to provide education and training for employees on the use of fire extinguisher so that they can conduct effective fire fighting at work site. I hope that this journal will be a help of you in enhancing safety awareness in your work site. Interisk Asia Pte Ltd Director Akira Yamamura is a MS&AD Insurance Group company specialized in risk management survey research and consulting services. For inquiry about consultation and seminar etc. for companies expanding business in the ASEAN countries, please feel free to contact the nearest Mitsui Sumitomo Insurance or Aioi Nissay Dowa Insurance sales representatives. International Section, Corporate Planning Department TEL Interisk Asia is a MS&AD Insurance Group company which was established in Singapore to provide risk management services, such as fire safety, flood risk management, electrical safety, occupational safety and burglar risk management to our clients in the ASEAN countries. For inquiry, please feel free to contact us. Interisk Asia Pte Ltd 16 Raffles Quay #19-05A Hong Leong Building Singapore TEL Fax The purpose of this report is to provide our customers with the useful information to for the occupational safety and health management. There is no intention to criticize any individuals and parties etc. Copyright 2014 All Rights Reserved. 7