STANDARD OPERATING PROCEDURES. ELECTRICAL HAZARDS SAFETY PROCEDURES PURPOSE: To provide safety procedures for the removal of electric meters,

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1 PURPOSE: To provide safety procedures for the removal of electric meters, SCOPE: All firefighting personnel. I. ELECTRIC METERS: The following are safety procedures for the removal of an electric meter from the meter socket, as suggested by Memphis Light, Gas, and Water (MLGW). All personnel should be aware of electrical meter installations that do not cut service when the meter is removed. These meters are identified by the MLGW identification number when the first two (2) numbers begin with 21, 31, or 51, and are followed by three (3) letters. (EXAMPLE: 21GCL ) These meters are also called Continuous Duty Meters. These meters are not common to any particular size service and may be found on residential as well as commercial structures. MLGW identification numbers will ALWAYS begin with two (2) numbers followed by three (3) letters. Continuous Duty Meters Revised 2/1/09 1

2 Other electrical meters to be aware of are meters with the identification numbers beginning with 74 and 84 followed by three (3) letters. (EXAMPLE: 74TLC ) These meters are considered DANGEROUS! They are 480 volts and above. Memphis Firefighters should not attempt to remove meter! Caution! High Voltage! Meters beginning with 74 or 84 followed by (3) letters are 480 volts or above DO NOT ATTEMPT TO REMOVE METER!!! The identification number may be located anywhere on the face of the meter. REMEMBER: Some meters may have the number 21, 31, or 51 showing on the face of the meter, however: unless the number (21, 31, 51) is followed by three (3) letters of the alphabet, it is not a MLGW identification number. Revised 2/1/09 2

3 1. When approaching the meter installation, observe the socket, conduit or cables and service wires to determine any danger that may exist. II. REMOVING ELECTRIC METERS: 2. Remove the band or cover from the electric meter (utilizing barrel lock key) with caution to avoid breaking the glass cover, and to prevent the band or metal cover from coming in contact with the conductors. Revised 2/1/09 3

4 3. TURN-OUTS, BOOTS, HELMET (WITH FACE SHIELD DOWN), AND ELECTRICAL GLOVES MUST BE WORN BY THE INDIVIDUAL REMOVING THE ELECTRIC METER TO GUARD AGAINST POSSIBLE ELECTRICAL SHOCK. NOTE: Standing on a dry board or any insulating material will give added protection. 4. While standing to the side of the meter, grip the meter with one hand on the bottom and the other on the top of the glass cover. PULL THE METER DOWN AND OUT. This will remove the meter contacts from the compression clips of the meter socket. PROPER PPE SHOULD ALWAYS BE WORN! Revised 2/1/09 4

5 CONTINUOUS DUTY SERVICE BOX EQUIPPED WITH A BY-PASS LEVER 1. After safely removing the cover plate, stand to the side of the panel box and place one hand under the meter glass to support the meter as shown in the illustration below. This will prevent the meter from possibly falling during the following procedures: a. With the other hand, move the by-pass lever from the down position to the up position and lock it into place. This procedure electrically by-passes the meter and releases the grip on the meter contacts allowing the meter to be easily removed from the service. b. After removing the meter, stand to the side of the panel box and grip the by-pass lever. Pull the lever down in one continuous motion. This brings the lever back to its original position and disconnects the service. NOTE: This procedure may produce arcs when the by-pass contacts disconnect if a heavy electrical load is being placed on the service by facility it supplies. Revised 2/1/09 5

6 PROPER PPE SHOULD ALWAYS BE WORN! 2. Place the meter on the ground under the socket from which it was removed. Should there be several meters in a bank, this will indicate to the MLGW serviceman that the meter was removed from the socket directly above. 3. Remember the TOP terminals inside the meter box are still energized. Extreme caution should be exercised when working in the vicinity of energized wires, terminals or any place where electrical contact may be made. 4. An electrical meter removed, or any type of electrical service that has been disconnected by the Fire Department, should not be re-connected. Only MLGW personnel are authorized to restore electrical service. WARNING: UNDER NO CIRCUMSTANCES SHOULD AN ATTEMPT BE MADE TO REMOVE A METER FROM ITS SOCKET WITH AN AXE OR SLEDGE HAMMER. IF THE RETAINER RING THAT SECURES THE METER TO THE SERVICE CANNOT BE REMOVED, THE POWER SHOULD BE CUT ELSEWHERE. Revised 2/1/09 6

7 III. CUTTING SERVICE WIRES Cutting service wires to a building should be done only in extreme emergencies. If it has been determined the electric company cannot arrive on the scene in time, and if no main breaker is available for disconnecting the service, and if the meter cannot be removed from its socket, or if the removal of the meter does not de-energize the service, then the service wires may be cut. Only low voltage wires (less than 600 volts) should be cut. The cutting of service wires is a dangerous operation. The following precautions will help to minimize the dangers involved: 1. NEVER cut an electrical conductor whose voltage is in excess of 600 volts. This limits any conductor cutting to low voltage service wires. Primary wires are not to be cut by anyone other than MLGW. High voltage lines are not to be handled by anyone other than MLGW. 2. Use a properly insulated cutting tool to cut low voltage wires. The cutting tool should have a rating for use up to and including 600 volts. 3. Try to stand on a dry surface, such as a board or insulated ladder, when cutting low voltage lines. 4. NEVER cut more than one wire at a time. Failure to heed this precaution will result in a short circuit being made and the cutting tool will be badly damaged, and EXTREMELY HAZARDOUS arcing will occur. 5. Wear safety glasses to shield the eyes from electric flashes. Wear appropriate electric meter gloves and protective clothing to protect the skin from flash burns. 6. Before cutting service wires, make sure the wires will not drop into high voltage lines or whip into people or equipment. 7. After service wires are cut, the portion of the line going back to the pole will still be energized. 8. When cutting service wires, remember CUT ONLY ONE WIRE AT A TIME! Position the cut conductors so that the ends do not touch other conductors. Move cutting tool approximately six inches from the first cut and cut a second conductor. Position the second cut conductor so that the ends will not touch any other conductor. Revised 2/1/09 7

8 IV. ELECTRIC LINES LYING ON THE GROUND 1. At times the firefighter may be called to the scene of electric conductors lying on the ground. Such wires should always be considered energized. These wires may be high voltage or low voltage, therefore, NO attempt to move them should be made. 2. The first thing is to clear the area of people and make sure they are kept clear of the fallen wires. It should be noted that an electric wire lying on the ground may move about, (much the same as an unattended fire hose with the water turned on), because of the current flow being interrupted by automatic re-closing of substation breakers. Hence, make sure people are kept WELL CLEAR of fallen wires. 3. After insuring that people are being kept well clear of the wires, notify MLGW. Revised 2/1/09 8

9 V. SUPPRESSING CLASS C FIRES / SWITCH GEARS 1. Fires in energized electrical equipment occur quite frequently, but once the equipment is de-energized they can be handled with relative ease. The primary danger of electrical fires is the failure of emergency personnel to recognize shock hazards. Once the power has been shut off, these fires may self-extinguish. If they continue to burn, they will fall into either Class A or Class B fires. 2. Nonconductive extinguishing agents, such as carbon dioxide and halogenated agents (Halon) are preferred for use on fires involving energized electrical equipment. 3. Using water on energized equipment is discouraged unless absolutely necessary because of the inherent shock hazard. If water must be applied, it should be done from fog streams and at a distance. 4. Fires in transformers can present a serious health and environmental risk due to coolant liquids that contain PCB s (polychlorinated biphenyls). These liquids are flammable because of their oil base and are also extremely carcinogenic (cancer causing). Fires in transformers at ground level should be extinguished carefully with a dry chemical extinguisher, (Dry Powder). Above Ground Switch Gear (Transformer) Remember, USE DRY POWDER ONLY!!! Revised 2/1/09 9

10 VI. CONTROLLING FIRES IN ELECTRIC SUBSTATIONS 1. When fire officers determine that a fire is located in an electric substation, the officer should request MLGW to respond to the scene. 2. Under no circumstances should firefighting personnel enter an electric substation unless the area has been deemed safe by an employee of MLGW 3. If equipment is on fire: a) Set up Lightwater Operations. b) Request Haz-Mat team to respond. c) Extinguish fire using extreme caution as large amounts of mineral oil used to cool this equipment may become involved. The mineral oil used may have already reached its flash point! Revised 2/1/09 10