Current through all regulations passed and filed through September 16, 2024
(B) Definitions.
(1) "Fire-resistive construction" means a
method of construction which prevents or retards the passage of hot gases or
flames as defined by the fire-resistance rating.
(2) "Fire-resistance rating" means the
measured time in hours or fractions thereof that the material or construction
will withstand fire exposure, as determined by fire tests conducted in
conformity to recognized standards.
(C) Responsibility.
(1) The employer shall verbally and through
demonstration instruct the employee in the safe operation and maintenance of
cutting and welding equipment.
(2)
It shall be the duty of the employee to operate such equipment in accordance
with such instructions.
(D) Maximum pressure.
Under no condition shall acetylene be generated, piped (except
in approved cylinder manifolds), or utilized at a pressure in excess of fifteen
pounds per square inch gauge pressure.
(E) Gas welding and cutting.
(1) Equipment.
Only approved equipment, such as torches, regulators, or
pressure-reducing valves, acetylene generators, manifolds, cylinders, and
containers shall be used.
(2) Cylinders and containers.
(a) Marking.
Compressed gas cylinders shall be legibly marked, for the
purpose of identifying the content, with either the chemical or the trade name
of the gas. Such marking shall be by means of stenciling, stamping, or
labeling, and shall not be readily removed.
(b) Storage.
(i) Oxygen cylinders in storage shall be
separated from fuel-gas cylinders or combustible materials (especially oil or
grease), a minimum distance of twenty feet or by a noncombustible barrier no
less than five feet high, having a fire-resistance rating of no less than
one-half hour.
(ii) Cylinders, when
not in use, shall be protected from any heat-radiating objects or open flame
which could cause the cylinder to rupture or could cause the fusible plug to
melt.
(c) Valve
protection caps.
(i) All cylinders with a
water weight capacity of over thirty pounds shall be equipped with means of
connecting a valve protection cap or with a collar or recess to protect the
valve.
(ii) Employees shall be
responsible for using valve protection caps when cylinders are moved from place
to place or put in storage.
(iii)
Where carriers are provided for moving cylinders which are connected for use,
capping shall not be required but employees shall be responsible for seeing
that cylinder valves are closed and pressure is released from regulators,
hoses, and torches.
(d)
Regulator protection.
Welders and cutters shall be instructed to close valves on
oxygen and acetylene cylinders and bleed off hose pressure at the end of each
workshift, to prevent malfunction of the regulators.
(e) Transporting cylinders by crane or
derrick.
When cylinders are hoisted, they shall be secured on a cradle,
slingboard, or pallet. They shall not be hoisted or transported by means of
magnets or choker slings.
(f) Facilities for securely fastening
cylinders; responsibility.
The employer shall provide facilities for securely fastening
cylinders of compressed gas in an upright position.
(3) Hose and hose connections.
(a) Hose.
(i) Identification.
The color red shall be used for acetylene and other fuel-gas
hose. The color green shall be used for oxygen hose. The color black shall be
used for inert-gas and air hose.
(ii) Hose in which flashback has occurred.
Any length of hose in which a flashback has occurred and burned
in the hose shall be taken out of service.
(iii) Single hose with more than one gas
passage.
The use of a single hose having more than one gas passage, in
which a wall failure would permit the flow of one gas into the other gas
passage, is prohibited.
(iv) Hoses taped together - limitation.
When parallel lengths of oxygen and acetylene hoses are taped
together for convenience and to prevent tangling, no more than four inches out
of twelve inches shall be covered by tape.
(v) Damaged or defective hose.
Hose showing leaks, burns, worn places, or other defects
rendering it unfit for service shall have the damaged portion removed.
(b) Hose connections
and couplings.
(i) Hose connections for oxygen
and fuel-gas shall be distinguished from each other. Hose connections shall be
clamped or otherwise securely fastened in a manner that will withstand, without
leakage, twice the pressure to which they are normally subjected in service,
but in no case less than three hundred pounds per square inch.
(ii) Hose couplings shall be of the type that
cannot be unlocked or disconnected by means of a straight pull without rotary
motion.
(c) Pressure
reducing regulators.
Oxygen and fuel-gas pressure regulators, including their
related gauges, shall be in proper working order while in use.
(F) Arc
welding and cutting.
(1) Manual electrode
holders.
(a) Only manual electrode holders
which are specifically designed for arc welding and cutting, and are of a
capacity capable of safely handling the maximum rated current required by the
electrodes, shall be used.
(b) Any
current-carrying parts passing through the portion of the holder which the arc
welder or cutter grips in his hand, and the outer surfaces of the jaws of the
holder, shall be fully insulated against the maximum voltage encountered to
ground.
(2) Welding
cables and connectors.
(a) All arc welding
and cutting cables shall be of the completely insulated, flexible type, capable
of handling the maximum current requirements of the work in progress, taking
into account the duty cycle under which the arc welding or cutting unit is
working.
(b) Cables with splices
within ten feet of the holder shall not be used except that cables with
standard insulated connectors or with splices whose insulating quality is equal
to that of the cables are permitted.
(c) When it becomes necessary to connect or
splice lengths of cable one to another, substantial insulated connectors of a
capacity at least equivalent to that of the cable shall be used. If connections
are effected by means of cable lugs, they shall be securely fastened together
to give good electrical contact, and the exposed metal parts of the lugs shall
be completely insulated.
(d) Cables
in need of repair shall not be used.
(3) Ground returns and machine grounding.
(a) A ground return cable shall have a safe
current-carrying capacity equal to or exceeding the specified maximum output
capacity of the arc welding or cutting unit which it services. When a single
ground return cable services more than one unit, the safe current-carrying
capacity shall equal or exceed the total specified maximum output capacities of
all the units which it services.
(b) Pipelines containing gases or flammable
liquids or conduits containing electrical circuits, shall not be used as a
ground return.
(c) When a structure
or pipeline is employed as a ground return circuit, it shall be determined that
the required electrical contact exists at all joints. The generation of an arc,
sparks, or heat at any point shall cause rejection of the structures as a
ground circuit.
(d) When a
structure or pipeline is continuously employed as a ground return circuit, all
joints shall be bonded, and periodic inspections shall be conducted to ensure
that no condition of electrolysis or fire hazard exists by virtue of such
use.
(e) The frames of all arc
welding and cutting machines shall be grounded either through a third wire in
the cable containing the circuit conductor or through a separate wire which is
grounded at the source of the current. Grounding circuits, other than by means
of the structure, shall be checked to ensure that the circuit between the
ground and the grounded power conductor has resistance low enough to permit
sufficient current to flow to cause the fuse or circuit breaker to interrupt
the current.
(f) All ground
connections shall be inspected to ensure that they are mechanically secure and
electrically adequate for the required current.
(4) Operating instructions.
Employers shall instruct employees in the safe means of arc
welding and cutting as follows:
(a)
When electrode holders are to be left unattended, the electrodes shall be
removed and the holders shall be so placed or protected that they cannot make
electrical contact with employees or conducting objects.
(b) Hot electrode holders shall not be dipped
in water.
(c) When the arc welder
or cutter has occasion to leave work or to stop work for any appreciable length
of time, or when the arc welding or cutting unit is to be moved, the power
supply switch to the equipment shall be opened.
(5) Shielding.
Arc welding and cutting operations shall be shielded by
noncombustible or flameproof screens which will protect employees working in
the vicinity from the direct rays of the arc.
(6) Overcurrent protection.
All welding machines shall be protected by an overcurrent
device.
(7) Disconnecting
means.
(a) A disconnecting means shall be
provided in the supply for each alternating-current transformer and
direct-current rectifier arc welder which is not equipped with a disconnect
mounted as an integral part of the welder.
(b) The disconnecting means shall be a switch
or circuit breaker, and its rating shall be no less than that necessary to
accommodate overcurrent protection.
(G) Welding or cutting of containers.
No welding, cutting, or work utilizing a torch shall be
performed on used drums, barrels, tanks, or other containers until they have
been cleaned and purged of materials which when subjected to heat might produce
flammable or toxic vapors.
(H) Eye and ear protection.
See rule
4123:1-3-03 of the Administrative Code, "Personal
protective equipment".
(I)
Protection from sparks or falling objects.
(1)
Cutting or welding shall be permitted only in areas that are or have been made
fire safe.
(2) Screens or shields
shall be provided for the protection of employees or combustible materials
exposed to falling objects or sparks.
