Chapter 12 HOT WORK OPERATIONS. Purpose:

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1 Chapter 12 Hot Work Operations Chapter 12 HOT WORK OPERATIONS Purpose: To provide written procedures to prevent the outbreak of fire, fire alarm activations, and smoke and odor migration in buildings resulting from any temporary operation involving the use of open flames or which produces heat and / or sparks. This includes, but is not limited to: brazing, cutting, grinding, torch soldering, thawing pipes, torch applied roofing and welding. Definitions: Hot Work: Any operation producing flame, sparks or heat including cutting, welding, brazing, grinding, sawing, torch soldering, thawing frozen pipes, applying roof covering etc. Hot Work Permit: A special permit, which authorizes Hot Work activities at a specific location and time. The permit will be properly filled out, displayed on site and returned to the employee s supervisor when the hot work is complete. Permits contain a checklist to be completed prior to commencing hot work activities and also at the conclusion of the hot work. The Hot Work permit format may be specified by the customer or the company form set forth in the form s section of this manual. Fire Watch: A trained individual stationed in the hot work area who monitors the work area for the beginnings of potential, unwanted fires both during and after hot work. Individuals must be trained and familiar with the operation of portable fire extinguishers and methods to activate fire alarm systems. A fire watch will remain on site between 30 minutes after completion of cutting or welding operations to detect and extinguish possible smoldering fires. Personal Protective Equipment (PPE) Personal protective equipment for eyes, face, head, and extremities, respiratory protection and protective shields and barriers shall be used and maintained in a sanitary and reliable condition. 169

2 Hayward Electric Injury & Illness Prevention Program First Aid Equipment Appropriate first aid equipment shall be available at all times during the Hot Work operations. Ventilation Adequate ventilation (natural, mechanical, or respirator) must be provided for all welding, cutting, brazing, and related operations. Adequate ventilation depends upon the following factors: 1. Volume and configuration of space in which operation occur. 2. Number and types of operations generating contaminants. 3. Allowable levels of specific toxic or flammable contaminants being generated. 4. Location of the welder s and other person s breathing zones in relation to the contaminants or sources. Natural ventilation is acceptable for welding, cutting, and related processes where the necessary precautions have been taken to keep the welder s breathing zone away from the welding or brazing plume. Special Ventilation Concerns: Certain materials, sometimes contained in the consumables, base metals, coatings, or atmospheres of welding or cutting operations, have low or very low Occupational Exposure Limits (OEL) American Conference of Governmental Hygienists, Threshold Limit Value 1.0 mg m -3 or less. Among these materials are: Antimony Arsenic Nickel Beryllium Cadmium Chromium Cobalt Copper Lead Manganese Mercury Nickel Selenium Silver Vanadi 170

3 Chapter 12 Hot Work Operations Whenever these materials are encountered as designated constituents in welding, brazing, or cutting operations, special ventilation precautions shall be taken to assure the level of contaminants in the atmosphere is below respective OEL s or other recommended levels. The Material Safety Data Sheets (MSDS), for the materials listed above must be readily accessible to verify their presence. Hot Work Procedures: 1. Cutting and/or welding equipment will be examined to see that it is satisfactory operating condition. 2. Hot work should not be performed if the work can be avoided or performed in a safer manner. When practical, objects to be welded, cut or heated should be moved to a designated safe location, (i.e. maintenance shops). 3. If hot work must be performed, a Hot Work Permit must be completed. 4. All precautions on the Hot Work Permit must be met prior to any work commencing. The supervisor or the employee performing the hot work will complete the permit. 5. The Hot Work Permit is only good for the date specified on the permit. 6. A Hot Work Permit must be displayed at the work site during all hot work activities. 7. All occupants must be suitably protected against hazards generated by the work. i.e. heat, sparks, fumes, welding rays, etc. 8. Before hot work begins: a. Fully charged and operable fire extinguishers, appropriate for the type of fire shall be available at the work area. b. Flammable and ignitable materials and debris must be moved at least 35 feet from the hot work area or covered and protected from the hot work by fire resistant material. c. Cutting or welding on pipes or other metal in contact with combustible walls, partitions, ceilings, or roofs shall not be undertaken if the work is close enough to cause ignition by conduction. d. Where welding or cutting is done in close proximity to a sprinkler head, a wet rag shall be laid over the head then removed at the conclusion of the welding or cutting operation. Special precautions shall be taken to avoid accidental operation of automatic fire detection or suppression systems (e.g. sprinklers or halon systems). 171

4 Hayward Electric Injury & Illness Prevention Program e. Explosives, compressed gas cylinders or stored fuel must be moved at least 50 feet from the hot work area or covered and protected from the hot work by fire resistant material. f. Smoke and fire detectors in the immediate area of the hot work must be temporarily disabled until the hot work is completed. g. Adequate ventilation is being used (especially when cutting or welding materials with painted or metal coated surfaces). h. Building occupants have been protected or isolated from the hot work area. i. Cracks or holes in floors, walls, and ceilings (including ductwork) are properly covered or plugged. j. Drums, barrels and tanks have been cleaned and purged of flammables and toxics, all tank feeds are closed, and the tank vented. k. A Fire watch is implemented if conditions warrant. If no fire hazards or combustible exposures are present a fire watch is not required. l. Workers and Fire Watch personnel are trained in the use of fire extinguishing equipment and how to sound a fire alarm. 9. When hot work is complete: a. The work area and any potentially affected surrounding areas are inspected for fire, fire damage or the potential for fire for a minimum of 30 minutes following completion of the hot work. b. Smoke / fire alarms that were disabled because of hot work are reactivated. c. Hot work permit is closed out d. Completed permit is returned to worker s supervisor who then submits the completed permit to the appropriate client s personnel or Office. General Safety Rules for Welding, Cutting and Hot Work 1. No device or attachment facilitating or permitting mixture of air or oxygen with combustible gases prior to consumption, except at the burner or in a standard torch or blowpipe, shall be allowed unless approved for the purpose. 2. The user shall not transfer gases from one cylinder to another to mix gases in a cylinder. 3. Acetylene gas shall not be brought in contact with unalloyed copper except in blowpipe or torch. 4. Oxygen shall never be used from cylinders through torches or other devices equipped with shutoff valves, without reducing the pressure through a suitable regulator attached to the cylinder valve or manifold. 5. Fuel gas shall never be used from cylinders through torches or other devices equipped with shutoff valves, without reducing the pressure through a suitable regulator attached to the cylinder valve or manifold. Exception: low pressure containers of propane or MAPP gas. 172

5 Chapter 12 Hot Work Operations 6. Cylinders, valve regulators, hose and other apparatus and fittings, containing or using oxygen shall be kept free from oil and grease. Oxygen cylinders and apparatus and fittings shall not be handled with oily hands, gloves or greasy materials. 7. When moving compressed gas cylinders by crane, suitable cradles shall be used in order to reduce the possibility of dropping. Ordinary rope slings or electro-magnets shall not be used. 8. Oxygen and fuel gas cylinders shall be placed far enough away from the welding position that they will not be unduly heated by radiation from heated materials, by sparks or slag, or by misdirection of the torch flame. Hot Work in Confined Spaces Hot Work Operations performed within confined spaces must also comply with the company s Confined Space Permitting procedures. Training Supervisors assigned to supervise welding, cutting, brazing operations shall be trained in the safe operation of a Hot Work operation. The supervisor shall have knowledge of the equipment and the work area to properly supervise the operation. Employees assigned to welding, cutting, brazing operations shall be properly instructed and judged qualified to operate such equipment. Instruction should include the proper operation of the equipment being used, recognition of safety hazards associated with such operation and methods to avoid or minimize exposure to identified safety hazards. Employees assigned to fire watch duties shall be trained in the following: 1. Recognition of fire hazards in the work area. 2. Method to trigger a fire alarm (i.e., pull fire alarm box, call 911, shout fire, etc.) to warn other workers and to summon fire fighters. 3. Proper operation of fire fighting equipment associated with the hot work. All employees and supervisors shall review prior to starting the Hot Work the following topics: 1. The location and proper use of all fire fighting equipment. 2. The method(s) to trigger a fire alarm to warn workers in the immediate area and who specifically is assigned the duty to call for outside assistance (i.e., dial 911, etc.), if required. This person will normally also be assigned to lead fire fighters back to the Hot Work area. 3. The location of emergency exits. 4. The meeting location of employees outside the work area in the event that the area must be evacuated so that all employees can be accounted for. 173

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