WELDING, CUTTING AND BRAZING
29 CFR 1910.252-254
Ursinus College, Collegeville, PA
____________________________________________________________________________________
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 1910.252, 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”, A3.0-1969.
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.
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WELDING, CUTTING AND BRAZING
29 CFR 1910.252-254
Ursinus College, Collegeville, PA
____________________________________________________________________________________
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 1910.252(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.
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WELDING, CUTTING AND BRAZING
29 CFR 1910.252-254
Ursinus College, Collegeville, PA
____________________________________________________________________________________
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-1-1962, or the “Safety Standard for Transformer-Type ArcWelding Machines”, ANSI C33.2-1956, 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.
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WELDING, CUTTING AND BRAZING
29 CFR 1910.252-254
Ursinus College, Collegeville, PA
____________________________________________________________________________________
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.
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WELDING, CUTTING AND BRAZING
29 CFR 1910.252-254
Ursinus College, Collegeville, PA
____________________________________________________________________________________
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,
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WELDING, CUTTING AND BRAZING
29 CFR 1910.252-254
Ursinus College, Collegeville, PA
____________________________________________________________________________________
(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
1910.133, 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 1910.252(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
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WELDING, CUTTING AND BRAZING
29 CFR 1910.252-254
Ursinus College, Collegeville, PA
____________________________________________________________________________________
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 1910.132. 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.
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WELDING, CUTTING AND BRAZING
29 CFR 1910.252-254
Ursinus College, Collegeville, PA
____________________________________________________________________________________
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
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WELDING, CUTTING AND BRAZING
29 CFR 1910.252-254
Ursinus College, Collegeville, PA
____________________________________________________________________________________
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 19190.1001-1048.
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:
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WELDING, CUTTING AND BRAZING
29 CFR 1910.252-254
Ursinus College, Collegeville, PA
____________________________________________________________________________________
(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 1910.252(f)(5) through (12) for each specific
material shall be followed.
3 March 2004
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WELDING, CUTTING AND BRAZING
29 CFR 1910.252-254
Ursinus College, Collegeville, PA
____________________________________________________________________________________
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
4-6” from arc or torch
6-8” from arc or torch
8-10” from arc or torch
10-12” from arc or torch
MINIMUM AIR FLOW*
150
275
425
600
DUCT DIAMETER**
3
3
4
5
* Cubic feet/minute
** Inches-Nearest half-inch duct diameter based on 4,000 feet per minute velocity in pipe
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