1. All Ursinus personnel who weld, cut or braze shall be familiar with the requirements of this section.

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1 It is the policy of Ursinus College that all welding, cutting, and brazing operations comply with the applicable safety, health, and fire regulations and codes as stated in the Occupational Safety and Health Act (OSHA), the National Fire Codes published by the National Fire Protection Association (NFPA), this section and other applicable sections of this handbook. GENERAL REQUIREMENTS: 1. All Ursinus personnel who weld, cut or braze shall be familiar with the requirements of this section. 2. This section covers the general safety requirements for welding, cutting, and brazing operations. The governing regulation, 29 CFR , and NFPA 51B should be consulted for more detailed information. DEFINITIONS: 1. Welder and Welding Operator: Any operator of electric or gas welding and cutting equipment. 2. Approved: A rating indicating that an item has been listed or approved by a nationally recognized testing laboratory, such as Factory Mutual Engineering Corp. or Underwriters laboratories, Inc. 3. All other welding terms used in accordance with American Welding Society, Terms and Definitions, A COMPRESSED GAS CYLINDERS: 1. General: Mixtures of fuel gases and air or oxygen may be explosive and shall be guarded against unintentional sources of ignition. Only approved apparatus such as torches, regulators or pressure-reducing valves, acetylene generators, and manifolds shall be used. a. Compressed gas cylinders shall (1) Be kept away from excessive heat, (2) Not be stored where they might be damaged or knocked over by passing or falling objects, (3) Be stored at least 35 feet away from highly combustible materials, and (4) Be provided with a suitable chain or other device to secure cylinders from falling over. b. Cylinders shall be capped whenever they are not in use or connected for use. (Exception: Cylinders not designed for caps are not required to be capped.) c. Acetylene cylinders shall be stored and used in a vertical, valve-end-up position only. d. Oxygen cylinders in storage shall be separated from fuel-gas cylinders or combustible materials (especially oil or grease by at least 20 feet or by a noncombustible barrier at least 5 feet high having a fire-resistant rating of at least one-half hour. 1

2 e. Cylinders, empty or full, shall never be uses as rollers or supports. f. Fuel-gas shall never be used through torches or other devices equipped with shutoff valves unless the pressure is reduced through a suitable regulator attached to the cylinder valve or manifold. g. Cylinder valves shall always be opened slowly. h. Acetylene cylinder valves shall not be opened more than one and one-half turns of the spindle and, preferably, no more than three-fourths of a turn. i. Where a special wrench is required, it shall be left in position on the stem of the valve while the cylinder is in use so that the fuel-gas flow can be quickly turned off in case of emergency. In the case of manifolded or coupled cylinders, at least one wrench shall always be available for immediate use. j. Safety devices must not be altered. k. Manifold systems shall meet all the requirements of 29 CRF (a)(3)(1). HOSE AND HOSE CONNECTIONS: 1. Hose for Oxy-Fuel Gas Service: Hose for oxy-fuel gas service shall comply with the Specification for Rubber Welding Hose, 1958, Compressed Gas Association and Rubber Manufacturers Association. a. When parallel lengths of oxygen and acetylene hose are taped together for convenience and to prevent tangling, not more than 4 inches of each 12 inches shall be covered by tape. b. Hose connections shall comply with the Standard Hose Connection Specifications, 1957, Compressed Gas Association. c. Hose connections shall be clamped or otherwise securely fastened so that the connections are able to withstand, without leakage, twice the pressure to which they are normally subjected in service, but in no case to less than 300 pounds per square inch. Oil-free air or an oil-free inert gas shall be used for the test. d. Hose showing leaks, burns, worn places, or other defects rendering it unfit for service shall be repaired or replaced. 2. Pressure-Reducing Regulators: a. Pressure-reducing regulators shall be used only for the gas and pressures for which they are intended. The regulator inlet connections shall comply with Regulator Connection Standards, 1958, Compressed Gas Association. 2

3 b. When regulators or parts of regulators, including gauges, need repair, the regulator shall be returned to the manufacturer for repair. c. Gauges on oxygen regulators shall be marked USE NO OIL. d. Union nuts and connections on regulators shall be inspected before use to detect faulty seats that might cause leakage of gas when the regulators are attached to the cylinder valves. The use of plastic joint tape is recommended. 3. Regulator Safety: All regulators and hose shall be checked daily for damage or worn parts. Anti-flashback valves shall be used between the hoses and regulators. 4. Operations and Safety Rules: Workers in charge of the oxygen or fuel-gas supply equipment, including generators, and oxygen or fuel-gas distribution piping systems shall be instructed and judged competent by their supervisor before being left in charge. Rules and instructions covering the operation and maintenance of this equipment shall be readily available. Basic safety rules for safe oxy-acetylene welding (Exhibit WC-1) shall be posted in all welding shop or stationary welding operations. ARC WELDING AND CUTTING EQUIPMENT: 1. Equipment: Only approved arc welding equipment shall be used. Apparatus must comply with the Requirements for Electric Arc-Welding Apparatus, National Electrical Manufacturers Association (NEMA) EW , or the Safety Standard for Transformer-Type Arc- Welding Machines, ANSI C , Underwriter s Laboratories. a. On all types of arc welding machines, the control apparatus shall be enclosed except for the operating wheels, levers, or handles. b. Input power terminals, tap change devices, and live metal parts connected to input circuits shall be completely enclosed and accessible only by means of tools. c. Terminals for welding leads should be protected from accidental electrical contact by personnel or by metal objects such as vehicles and crane hooks by: (1) Dead-front receptacles for plug connections, (2) Recessed openings with non-removable hinged covers, and (3) Heavy insulating sleeving or taping or other equivalent electrical and mechanical protection. 3

4 d. When a welding lead terminal intended to be used exclusively for connection to work is connected to the grounded enclosure, it is necessary to use a connector at least two American Wire Gauge (AWG) sizes smaller than the grounding conductor and the terminal shall be marked to indicate that it is grounded. e. No connection for portable control devices, such as push buttons to be carried by the operator, shall be connected to an a.c. circuit higher than 120 volts. Exposed metal parts of portable control devices operating on circuits above 50 volts shall be grounded by a grounding conductor in the control cable. f. Auto transformers or a.c. reactors shall not be used to draw welding current directly from any a.c. power source having a voltage exceeding 80 volts. g. All ground connections shall be checked to determine that they are mechanically strong and electrically adequate for the required current. 2. Operations and Maintenance: a. Before operations begin, all connections to the machine shall be checked to make certain that they are properly made. The work lead shall be firmly attached to the work and magnetic work clamps shall be freed from adherent metal particles of splatter on contact surfaces. Coiled welding cable shall be spread out before use to avoid serious overheating and damage to insulation. b. Grounding of the welding machine frame shall be checked before each use. Special attention shall be given to safety ground connections of portable machines. c. There shall be no leaks of cooling water, shielding gas, or engine fuel. d. Proper switching equipment for shutting down the machine shall be provided. e. Printed rules and instructions covering operation of equipment supplied by the manufacturers shall be strictly followed. f. When not in use, electrode holders shall be placed so that they cannot make electrical contact with persons, conducting objects, fuel, or compressed gas tanks. g. Cables with splices within 10 feet of the holder shall not be used. The welder shall not coil or loop welding electrode cable around parts of his/her body. h. The operator shall report any equipment defect or safety hazard to the supervisor and the use of the equipment shall be discontinued until its safety has been assured. Repairs shall be made only be qualified personnel. 4

5 i. Machines that have become wet shall be thoroughly dried and tested before being used. j. Workers designated to operate arc-welding equipment shall have been properly instructed and qualified to operate such equipment. This training shall be documented by the supervisor and maintained on file for the duration of the worker s employment. FIRE PREVENTION AND PROTECTION: 1. Fire Hazards: Welding and cutting shall not be performed unless combustible objects within 35 feet of the work area are removed. Immovable combustibles shall be protected with flameproof covers. 2. Floor and Wall Openings: Wherever there are floor or wall openings or cracks that cannot be closed, precautions shall be taken to ensure that combustible materials in adjacent areas are not exposed to sparks. 3. Fire Extinguishing Equipment: Suitable fire extinguishing equipment shall be readily available. Such equipment may include pails of water, buckets of sand, water hose, or portable extinguisher, depending upon the nature and quantity of the combustible material exposed. 4. Inspection of New Work Areas: Before cutting or welding is permitted in other than established welding and cutting shop areas, the supervisor shall inspect the area. In granting authorization to proceed, the supervisor shall designate precautions to be followed via a form Permit for Welding, Cutting, and Burning (Exhibit 2). 5. Fire Watch: a. Anytime welding or cutting operations are performed in a location where a fire might develop, a fire watch shall be provided. b. Fire watchers shall (1) Be trained in the use of fire extinguishing equipment, 5

6 (2) Be familiar with procedures for sounding a fire alarm, and (3) Watch for fires in all exposed areas and try to extinguish them only when obviously within the capacity of the equipment available, or otherwise sound the alarm. c. A fire watch shall be maintained for at least one half hour after completion of welding or cutting operations to detect and extinguish possible smoldering fires. PERSONAL PROTECTION: 1. Eye Protection: a. Helmets with face shields shall be used during all arc welding or arc cutting operations, excluding submerged arc welding. Helpers or attendants shall be provided with proper eye protection. b. Goggles or other suitable eye protection shall be used during all gas welding or oxygen cutting operations. Spectacles without side shields, with suitable filter lenses, are permitted for use during gas welding operations on light work, for torch brazing, or for inspection. c. All operators and attendants of resistance welding or resistance brazing equipment shall use transparent face shields or goggles to protect their faces or eyes, as required. d. Eye protection, in the form of suitable goggles as described in 29 CFR , shall be provided where needed for other brazing operations. e. All helmets with face shields, goggles, and glasses used as personal protective equipment shall meet the requirements of 29 CFR (e)(2)(ii). 2. Protection from Arc Welding Rays: a. Where the work permits, the welder should be enclosed in an individual booth painted with a finish of low reflectivity, such as zinc oxide (an important factor for absorbing ultraviolet radiations) and lamp black, or enclosed with noncombustible screens similarly painted. Booths and screens shall permit circulation of air at floor level. Workers or other persons adjacent to the welding areas shall be protected from the rays by noncombustible or flameproof screens or shields or they must wear appropriate goggles 6

7 b. Where the work does not permit the welder to work in an enclosed booth, portable screens to prevent passage of ultraviolet light shall be used. 3. Protective Clothing: a. Employees exposed to the hazards created by welding, cutting, or brazing operations shall be protected by personal protective equipment in accordance with the requirements of 29 CFR Appropriate protective clothing required for any welding operation will vary with the size, nature, and location of the work to be performed. Clothing should be free of oil and grease. Woolen clothing is recommended over cotton or synthetic materials. b. Flame-resistant gauntlets, gloves, and aprons made of leather or other flameresistant material to withstand radiated heat and sparks must be used. Gloves shall be worn when cleaning and brushing surfaces to be welded and also when wire brushing weld metal. c. For heavy work, fire-resistant leggings, high boots, or similar protection must be used. WELDING IN CONFINED SPACES: 1. Applications: Confined space is a relatively small or restricted space such as a tank, boiler, pressure vessel, or small compartment of a ship. (For full confined-space entry and working procedures, see Permit-Allowed Confined Space section of the Physical Plant Safety Manual.) 2. Ventilation: Adequate ventilation is a prerequisite to work in confined spaces. For ventilation requirements see Ventilation and Permit-Allowed Confined Spaces sections of the Physical Plant Safety Manual, as well as the end of this section. 3. Gas Cylinders and Welding Machines: When welding or cutting is being performed in confined spaces, the gas cylinders and welding machines shall be left on the outside. Before operations begin, heavy portable equipment mounted on wheels shall be securely blocked to prevent accidental movement. 7

8 4. Small Opening Entry: a. Where a welder must enter a confined space through a manhole or other small opening, means shall be provided for quickly removing the welder in case of emergency. b. When safety belts and lifelines are used for this purpose they shall be attached to the body in such a way that the welder s body cannot be jammed in a small exit opening. c. A trained and qualified attendant with a preplanned rescue procedure shall be stationed outside to observe the welder at all times and to initiate rescue operation s if necessary. See Permit-Allowed Confined Space section for specific qualifications for attendants. 5. Suspension of Welding Operations: a. When arc welding is suspended for 30 minutes or longer, all electrodes shall be removed from the holders and the holders carefully located so that accidental contact cannot occur, and the machine shall be disconnected from the power source. b. Whenever the torch is not to be used for 30 minutes or longer, the torch valves shall be closed and the fuel-gas and oxygen supply to the torch shut off outside the confined area. Where practicable, the torch and the hose shall also be removed from the confined space. c. After welding operations are completed, the welder shall mark the hot metal provide some means of warning other workers. HEALTH PROTECTION AND VENTILATION: 1. Contamination Exposure: The following factors in arc and gas welding govern the amount of contamination to which welders may be exposed: a. Dimensions of spaces in which welding is to be done (with special regard to height of ceiling), b. Number of welders and 8

9 c. Possible evolution of hazardous fumes, gases, or dust based on the metals involved. 2. Welding Screens: When welding must be performed in a spaced entirely screened on all sides, the screens shall be arranged so that no serious restriction of ventilation exists. It is desirable to have the screens mounted about 2 feet above the floor, unless the work is performed at a level so low that the screen must be extended nearer to the floor to protect nearby workers from the glare of welding. 3. Ventilation: a. Allowable concentrations: Exhaust or ventilating systems shall be arranged to keep the amount of toxic fumes, gases, or dusts below the maximum allowable concentration as specified in 29 CFR 1910 or the American Conference of Governmental Industrial Hygienists (ACGIH) threshold limit values for each material, whichever is more stringent. For further information, consult the MSDS for the particular material or 29 CFR b. Mechanical ventilation: (1) Mechanical ventilation shall be provided when welding or cutting is done on metals not covered in paragraph (3) below, and when the operation is performed in: (a) A space of less than 10,000 cubic feet per welder, (b) A room having a ceiling height of less than 16 feet, or (c) Confined spaces or where the welding space contains partitions, balconies, or other structural barriers that significantly obstruct crossventilation. (2) Mechanical ventilation shall be at the minimum rate of 2,000 cubic feet per minute per welder, except where local exhaust hoods, and booths (as per paragraph (3) below or supplied-air respirators approved by the National Institute of Occupational Safety and Health/Mine Safety and Health Administration (NIOSH/MSHA) for such purposes are provided. (3) Mechanical local exhaust ventilation shall be by means of either of the following: 9

10 (a) Hoods: Freely movable hoods intended to be placed by the welder as near as feasible to the work being welded. Hoods shall be provided with an exhaust rate of 100 linear feet per minute in the welding zone. Ventilation rates required to accomplish this control velocity using a 3-inch wide flanged suction opening are shown in Exhibit WC-3. (b) Fixed enclosure: A fixed enclosure with a top and not less than two sides that shall provide a minimum exhaust rate of at least 100 linear feet per minute. c. Ventilation in confined spaces: (1) All welding and cutting operations in confined spaces shall be adequately ventilated to prevent the accumulation of toxic materials or possible oxygen deficiency. This applies not only to the welding space but also to the immediate vicinity. All replacement air shall be clean and respirable. (2) When it is impossible to provide such ventilation, supplied-air respirators or hose masks approved by NIOSH/MSHA for this purpose shall be used. (3) In areas immediately hazardous to life, supplied-air respirators, hose masks with blowers, or self-contained breathing equipment shall be used. The breathing equipment must be approved by NIOSH/MSHA. (4) Where welding operations are performed in confined spaces and where welders and helpers are provided with supplied-air respirators, hose masks with blowers, or self-contained breathing equipment approved by NIOSH/MSHA, a trained and qualified worker also equipped with such equipment shall be stationed on the outside of such confined spaces to ensure the safety of those working within. (5) Oxygen must never be used for ventilation. d. Other Compounds: For welding or cutting operations involving fluorine compounds, zinc, lead, beryllium, cadmium, mercury, cleaning compounds, or stainless steel, the requirements found in 29 CFR (f)(5) through (12) for each specific material shall be followed. 3 March

11 EXHIBIT WC-1 10 BASIC RULES FOR OXYACETYLENE WELDING 1. Blow out cylinder valve before connecting the regulator. 2. Release the adjusting crew on the regulator before opening the cylinder valve. 3. Stand to one side of regulator before opening the cylinder valve. 4. Open cylinder valve slowly. 5. Do not use compressed acetylene in a free state at pressures more than 15 psi. 6. Purge acetylene and oxygen passages individually before lighting the torch. 7. Light the acetylene before opening the oxygen on the torch. 8. Never use oil or grease on regulators, tips, etc. in contact with oxygen. 9. Do not use oxygen as a substitute for air. 10. Keep work areas clear of combustible materials at all times. EXHIBIT WC 2 PERMIT FOR WELDING, CUTTING AND BURNING BUILDING ROOM NUMBER NATURE OF WORK EQUIPMENT OPERATOR PREWORK INSPECTION BY DATE OF WORK STARTING TIME FINISH TIME SURPERVISOR PERMIT ISSUED BY DATE ISSUED EXHIBIT WC-3 WELDING ZONE MINIMUM AIR FLOW* DUCT DIAMETER** 4-6 from arc or torch 6-8 from arc or torch 8-10 from arc or torch from arc or torch * Cubic feet/minute ** Inches-Nearest half-inch duct diameter based on 4,000 feet per minute velocity in pipe 11