Arc-eye, or welder's flash, is an inflammation of the cornea, caused by ultraviolet radiation from the arc during welding. The sufferer is usually unaware that they have been significantly exposed until several hours later.
The symptoms of arc-eye typically appear several hours after exposure, when the eyes become red, watering and painful, often with a gritty feeling. They may become sensitive to light.
The symptoms can be relieved by special eye drops. It is advisable to seek medical advice, since there may also be a foreign body or bodies in the eye. The effects of arc eye are only temporary and the symptoms generally clear up within a day or so.
It is difficult to predict when arc-eye will occur, since it depends on the intensity of the radiation and the duration of exposure. The intensity of the radiation is strongly dependent on the distance from the arc.
It is recommended that personnel should not be exposed to the arc without adequate protection in the form of screening or personal eye protection at a distance less than 10 metres.
The damaging radiation is not visible, so it is essential to choose the right scale of filter for the radiation. Many factors are involved in selecting the scale number of a protective filter which is suitable for welding and related techniques. In Europe, BS EN 169 should be consulted when making this selection. In the US, refer to ANSI/AWS F2.2 lens scale selector.