ILO Regulations about welding and cutting
Welding equipment – all types
- Welding and cutting operations shall be prohibited in proximity to places where combustible materials are stored, and in proximity to materials and plant where explosive or flammable dust, gasses or vapours are likely to be present or given off, except with special precautions.
- Arc welding and cutting operation that are carried out in places where other persons are working or passing shall be enclosed by means of suitable stationary or mobile screens.
- Wall and screens of both permanent and temporary protective enclosures for arc welding and cutting operations shall be so painted as to absorb harmful rays and prevent reflection.
- Suitable incombustible table or work-benches shall be provided for support of small or moderates-sized work during welding and cutting operations such as operations should not be undertaken on work resting directly on concentrate floors.
- Welding or cutting operations on containers filled with explosive or flammable substance shall be prohibited except in certain particulars cases where all appropriate safety precautions have been taken and subject to any conditions imposed by the competent authority, in particular for-
- The repairs by the electric welding process of water sealed gas holders, where such gas holders contains natural gas, liquefied petroleum gas (LPG) or similar flammable gas, other than acetylene, at more than the atmospheric pressure.
- Urgent repairs in the open air of gas mains, where such gas main contains natural gas, liquefied petroleum gas or similar flammable gas, other than acetylene, at more than atmospheric pressure.
– Welding or cutting operation on any container that has held explosive or flammable substances or in which flammable gases may have been generated shall only be undertaken after-
- The container has been thoroughly cleaned by steam or other effective means and found by air test to be completely free from combustible gases or vapours or.
- The air in the containers has been replaced by an inert gas.
Gas welding and cutting equipment
- Except when in use cylinders containing combustible gases shall not be kept in rooms where welding or cutting work is being done, and oxygen cylinder shall be kept separated from all other cylinder.
- Acetylene cylinder, when in use shall be kept in such a position that the head is higher than the base (foot).
- Liquefied gas cylinders shall be kept in an upright position
- Gas cylinder should not be allowed to fall over and shall not be dropped or subjected to violent shocks.
- Cylinders in use shall be held in position by straps, collars or chains to prevent them from falling over.
- The devices for holding the cylinders shall be such that the cylinders can be quickly removed in case of fire.
- Suitable designed equipment shall be used for transporting gas cylinders in industrial establishment.
- Protective caps on gas cylinders valves shall be in position when the cylinders are being moved or are not in used.
- Gas cylinders shall be kept at a safe distance from all operations which produce flames, sparks or molten metal or cause excessive heating of the cylinders.
- Oxygen cylinder shall not be handles with oiled hands or gloves, and grease or oil shall not be used as a lubricant on the valves, fitting, gauges or the regulating equipment.
- Acetylene and oxygen pipelines from generators or manifolds shall be painted with distinctive colours for identification.
- Welding or cutting burner shall not be hung from regulators or other equipment on the gas cylinders in the case of a prolonged stoppage of work they shall not be laid down until gasses have been completely shut off.
Arc welding & cutting machines
- Motor generators, rectifier, or transformers in arc welding or cutting machines and all current carrying parts, shall be protected against accidental contact with un insulated lives parts.
- Ventilation slots in transformers enclosure shall be so designed that no live parts is accessible through any slot.
- Frame of arc welding machines shall be effectively grounded.
Hand operated arc welding equipments
- Cable connector used in arc welding circuits shall be carefully insulated on the supply side.
- The outer surface of electrode holders including the jaw so far possible shall be fully insulated.
- Electrode holders should be provide with dices or shield, to protect the hands of the operators from the heat of the arcs.
Resistance welding machines
- In resistance welding machines, all current carrying parts accepts the welding contacts shall be completely enclosed.
- Resistance welding machines shall be equipped with line disconnecting switches, located at or near the machine.
- Power lead terminals shall be securely attached with screws and bolts, and plugs shall not be used except for control circuits.