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Health and safety in welding


Frequently asked questions

In most countries there is extensive legislation assigning responsibilities to employers to take reasonable care of the health and safety at work of their employees (e.g. in the UK the primary legislation is the Health and Safety at Work Act 1974).

See also Requirements for Health & Safety information and training

Welding is associated with several hazards to health and safety, and the employer needs to be able to ask informed questions:

The workshop environment

The employer needs to ensure that the lighting conditions are adequate for the work undertaken - giving extra lighting where necessary. Welders stand for long periods of time, since they must keep a very steady hand position, and this means that they can become quite cold if the workshop is not sufficiently well heated. Conversely in hot weather, the environment can become unbearably hot, and the welder has not got the option of removing clothing. Both overheating and underheating can cause fall in comfort, efficiency and productivity.

Housekeeping is extremely important to avoid slips, trips and falls, damage to equipment and fire.

Electrical safety

Clearly, the employer needs to establish the level of competence of the electrician who is given the task of wiring the installation, and the type of maintenance which the installation and the equipment will subsequently need. In the UK there is a requirement for periodic electrical checks to be done on power sources. The design of welding power sources themselves has gone through a number of changes, and for each, there are different standards of safety. The employer must ensure that his installation is correctly matched to the type he is using - for instance double insulated power sources should not be used with a separate earth lead to the workpiece.


Welding vapourises metals, and anything which is resting on the surface. This gives rise to fume, which is condensed fine particulate material. The fume is mostly oxides of the metals, including any alloying elements, but it also contains gases produced in the arc, such as ozone or oxides of nitrogen, and decomposition products from any paint or coating which was on the metal surface. The nature and quantity of this fume depends critically upon the welding process, the materials and the welding parameters. Some is harmful to health, for instance stainless steel fume contains chromium, and welding galvanised steel produces zinc fume.

Effects can vary from a bout of 'metal fume fever' to longer term, more serious problems if suitable fume removal is not carried out. There is guidance literature which may be consulted regarding the safe levels for each constituent, and the employer needs to be aware that for some fume constituents, there may be no safe level, and a statutory exposure limit may be imposed. Nickel, cobalt and stainless steel welding fume are the subject of statutory limits in the UK. Highly efficient exhaust apparatus is available. Some health surveillance may be necessary.


Welding environments are frequently noisy as other operations such as grinding, etc. may also be taking place. Some operations, such a de-slagging may take the noise up to such a level where it will damage workers hearing. In such cases this would mean that hearing protection is almost certainly required if the noise cannot be controlled by other means. Some health surveillance may also be necessary. To protect UK workers new noise exposure limits became law during 2006 that represented a significant lowering of statutory noise action levels from 85 dB(A) and 90dB(A) to 80 dB(A) and 85 dB(A) respectively.

Optical radiation

The welding process produces a large quantity of visible light, ultraviolet and infrared. Exposure to the radiation from an arc causes burns to the skin, and damage to the eyes. For this reason, welders need to wear clothing to protect their bodies and arms, regardless of the weather conditions. They also need efficient eye protection, which is usually supplied in the form of a protective shield. The precise choice of the shade of glass filter in these shields depends on the type of welding operation, since they vary in their light output.

Welders assistants also need protective clothing and eye protection. Passers-by should be protected by placing opaque or properly filtered screens around the work area.

Burns and mechanical hazards

Welders need good quality gloves, preferably leather gauntlets, safety boots or shoes and good quality cap and overalls. A leather apron may also be needed. Welding produces quantities of molten droplets of metal which are scattered in all directions. It is essential that the welder wears clothing which will not burn or melt, and which is stout enough to provide adequate protection.

In a workshop environment, suitable safety footwear is essential.

Gas bottles

Gas bottles need to be stored to conform with the regulations, and the welders need to be aware of the safety rules - such as the use of the correct regulator, tethering the cylinder so that it does not fall, keeping the outlets free from contamination such as oil or grease.

Welding in difficult situations - outdoors, confined spaces etc.

There are many work situations which add to the hazards of welding. Each must be assessed carefully, since there may be added hazards such as falls or asphyxiation. This is particularly true of work in confined spaces, where there is a very real risk of death, and the employer should make a critical assessment of the work to be done, and how it may be carried out safely. There may be statutory requirements in these situations. Guidance literature is available in most countries.


  1. The Health & Safety at Work Act 1974.
  2. Control of Substances Hazardous to Health Regulations 2002. LS Approved Code of Practice and Guidance.
  3. HSE publication EH 40/00 Occupational Exposure Limits (updated annually).
  4. HSE publication HSG139 The safe use of compressed gasses in welding, flame cutting and allied processes.
  5. HSE publication L25 Personal protective equipment at work (Guidance on the 1992 regulations).
  6. The Electrical Equipment Safety Regulations 1994.
  7. The Electricity at Work Regulations 1989.
  8. Confined Space Regulations 1997 - L101 Approved Code of Practice.
  9. Control of Noise at Work Regulations 2005 - L108 Approved Code of Practice

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