All welding arcs produce radiation, but as the energy ranges in the arcs are limited only certain wavelengths are generated. This radiation is divided into three categories Ultraviolet (UV), Visible Light and Infrared (IR). Of these three UV is the most likely to cause injury because its effects are not noticed by any of the senses at the time of exposure and so the effects only become apparent sometime later.

Arc welding and cutting processes produce all three forms of radiation UV, visible and IR, and present a greater hazard to the eyes than oxy-fuel gas flames which only produce visible and IR radiation.

Ultraviolet radiation is generated by arc welding, cutting and gouging processes but not by fuel gas processes. The most well known, and probable the most frequently suffered, effect from welding arcs is 'Arc eye' or 'welders flash' and this is caused by the effect of UV radiation on the outer eye.

Intense visible light may be generated by both electric arc and fuel gas processes. Prolonged exposure could lead to retinal burns, either photochemical or thermal, but it would be very difficult to work with such high levels of glare. In such situations the eye will naturally react to reduce exposure.

The intense heat of IR from both electric arc and fuel gas processes can cause retinal burns and cataracts.

The best protection for avoiding radiation damage to the eyes is to NEVER look at a welding arc without proper eye protection, however tempting that may be.

A wide range of filter glasses for welding helmets, screens and goggles are available for both gas and arc welding. One of the most common ways a welder can catch Arc Eye is by initiating the arc before having the welding helmet in place over the eyes.

Should a welder or other worker get a "flash", then arc eye drops can be applied by medical staff before going home and this will prevent the onset of arc eye, although the eyes may still feel a bit sore. Similarly, if arc eye does come on while still at work, it can be treated by on-site medical staff, or the patient can be taken to hospital or a medical centre.

Welders have a high incidence of eye injury due to foreign bodies, such as slag, spatter, sparks, dust and grit. Wire and chemicals can also present a hazard if mishandled.

Particles can enter the eye, if not protected, during de-slagging. As the slag is often removed while still hot, the injury can be compounded by adivitional corneal burns.

Spatter from the welding process can cause quite nasty injuries because of its temperature and velocity.

Debris from the grinding disks can get into the eye of the operator, and other workers at some distance from the actual grinding operation.

Chemicals used before and after welding such as degreasing and cleaning fluids, acetone, dye penetrant, acidic or caustic etching solutions, can be splashed into unprotected eyes, causing nasty injuries.

Many welders do not wear safety glasses or other form of eye protection when not actually welding, even when carrying out high-risk activities like de-slagging and it is this lack of protection which increases the number of incidence of this type of accident.

It is possible, when working in close proximity to other welders, that slag injury may be attributed to another welders activities, it is therefore a wise precaution to wear eye protection at all times in these circumstances.

In many cases, a foreign body in the eye can be seen on examination, and removed with care by a suitably qualified person. The eye can also be washed with sterile saline solution and this will often move the particle. If the eye is painful or the particle cannot be removed easily medical advice must be sought.

Any eye injury due to a foreign body should be examined and treated by suitably trained nurses, if they are present on site at the time of the accident.

Particulate fumes and gases can irritate or damage the eye. It is known that conjunctivitis may be caused by dust or fume associated with welding.

Every year there are reports in newspapers that contact lenses have been fused to welders eyes by the arc, causing nasty injuries.