Many people believe that the fumes from welding are a ‘nuisance’ and at worst only a mild risk to health, except, perhaps, for in the case of some specific metals. They also believe that drinking milk before welding will prevent the risk of ill-health from this activity – but neither of these statements is true... In recent years there’s been a growing body of evidence that welding fume has very specific ill-effects. The enforcing authorities now consider fumes from welding to be a high risk to health and expect them to be properly controlled. There’s no single workplace exposure limit (WEL) for welding fume, but there are a range of exposure levels for metal fumes, as low as 0.05 mg/M3 for hexavalent chromium, and other hazardous by-products of welding. As with most industrial fumes, different people are affected in different ways; some won’t get ill, some may be ill but only for a short time, and others may get permanent illnesses. Welding related illnesses There are a range of different illnesses associated with welding, such as:
- Pneumonia - welders, young as well as old, are particularly prone to a lung infection that can lead to severe and sometimes fatal pneumonia.
- Occupational asthma - particularly where stainless steels are being welded.
- Cancer - welding fume is internationally classified as possibly carcinogenic to humans, and although it’s primarily associated with stainless steel welding, it’s not limited to stainless steel fume.
- Metal fume fever – flu-like symptoms that get worse over the working week, do not usually have any lasting ill effects, and will clear over the weekend.
- Irritation of throat and lungs - gases and fine particles in welding fume can cause dryness of the throat, tickling, coughing or a tight chest. Extreme exposure to ozone can cause pulmonary oedema (fluid on the lungs).
- Temporary reduced lung function - as with metal fume fever, the effects tend to get worse through the working week but gradually clear over the weekend or when on holiday away from work.
There’s no simple way of identifying who will be affected or when - the only way to avoid the risk is to prevent or control exposure. Recommendations for reducing risk Of course, the best possible control is to avoid welding altogether – so think about simple solutions such as cold-jointing techniques. There are numerous mechanical fasteners such as bolts and rivets etc, and adhesive technologies have also progressed in recent years. For example, bonded metal structures are used in place of more traditional welded structures on a number of new car models. If avoiding welding isn’t possible, could the work be redesigned? Could there be fewer welds for example, or could you use thinner gauge material? Thinner gauge material will generally need less weld passes and lower power requirements on the welding set – and less power = less fume. What about adopting a different welding technique? In some applications, a MIG brazed joint can have the same physical properties as a full penetration weld – and with the advantage of producing less fume. As many modern welding sets can be set to allow brazing operations, there would be no additional cost to cover. Ventilation and requirements Where fume can’t be eliminated, local exhaust ventilation (LEV) will almost always be required. The very few exceptions, assuming work pieces are always free from contaminants (dirt, grease, excessive oil etc) and surface coatings (plating, paints etc), could include:
- Welding and hot cutting outdoors
- Oxy/acetylene flame welding
- A few minutes every hour of manual arc welding (unless on stainless steels)
- A few minutes every hour of flame or plasma cutting
Unfortunately, it’s not always clear what’s required – there’s such a wide range of welding activity that there’s no simple guide to cover what’s needed for every specific situation. In addition to the issues already mentioned, employers also have to consider whether the fume from the particular work is always controlled, or whether personal protective equipment (PPE) is required as a back-up – and also whether health surveillance should be provided for workers. Advice on occupational health issues Peninsula’s health and safety clients can always turn to their BusinessSafe consultant or call our 24 Hour Advice Service 0844 272 2785 for help and guidance in assessing whether their arrangements are satisfactory, or to learn what more they could be doing. Where you need to establish the precise levels of fume to which individual employees are exposed, our occupational hygiene service can take measurements - and where occupational health surveillance is required, our Health Assured Team can help you set up and maintain a system should it be deemed necessary.