Introduction
The common “arc eyes” is related to photokeratitis or ultraviolet keratitis which is a painful eye condition caused by exposure of insufficiently protected eyes to ultraviolet (UV) rays. Exposure may result from either natural (for example, intense sunlight) or artificial (for example, electric arc welding, photographer’s flood lamps, sun lamp in tanning salon, halogen desk lamp) sources. An arc eye is not usually noticed until 3 to 12 hours after exposure. Symptoms include increased tearing and a feeling of pain, likened to having sand in the eyes. If the eye is not treated, an infection could occur.
What are the common signs and symptoms of arc eyes?
- Red eyes
- Intense pain
- Watery eyes
- Sensation of “sand in the eye”
- Abnormal sensitivity to light
- Constricted pupils
- Eyelid twitching
How do arc eyes occur?
Any intense exposure to UV light can lead to photokeratitis or arc eyes. Welders who have failed to use adequate eye protection such as an appropriate welding helmet or welding goggles are known to develop arc eyes. However, people who are in close proximity but are not actively involved in welding are also known to develop arc eyes. Essentially, intense exposure due to the radiation causes thermal injury to superficial eye tissues.
Long hours in the sun expose the unprotected eyes to dangerous UVA and UVB rays and can actually cause sunburned eyes. Natural sources of UV radiation include bright sunlight reflected from snow or ice or, less commonly, from sea or sand. Fresh snow reflects about eighty percent of the UV radiation compared to a dry sandy beach (fifteen percent), or sea foam (twenty-five percent). This is especially a problem in Polar Regions and at high altitudes. With approximately every three-hundred metres of elevation above sea level, the intensity of UV rays increases by four percent. If you have spent several hours in the sun and your eyes are watering, itchy, sensitive to light, dry and gritty, it is likely that you have sunburned eyes. People spending many hours on the decks of cruise ships or sunbathing elsewhere, are prone to this. It can also occur when using tanning beds without proper eyewear or even skiing.
What can you do before seeing the eye care professional?
- Stay indoors and wear sunglasses to help with your increased light sensitivity
- Keep the eyes moist with preservative-free artificial tears
- Use over-the-counter (OTC) pain relievers to help with the pain and follow the recommended dosage
- Discontinue wearing contact lenses
- Do not rub the eyes
Treatment by an Eye Care Professional


The Eye Care Professional instills a topical anaesthetic to allow the eye to be examined and a painless dye called fluorescein is put onto the eye to aid the examination. The stain temporarily makes the eye look yellow but goes away after a few minutes. A special blue light is then used to evaluate the stained eye to determine if corneal damage is present. A damaged cornea, coupled with a history of ultraviolet light exposure, confirms the diagnosis of radiation eye burn or
arc eyes.
Cool, wet compresses over the eyes and artificial tears may alleviate local symptoms. A mild steroidal eye-drop and non-steroidal anti-inflammatory tablets are widely used to lessen inflammation and eye pain. Healing is usually rapid (one to four days). In addition, the patient is advised to remove contact lenses, not rub the eyes, and wear sunglasses until the symptoms improve.
Photokeratitis can be prevented by wearing sunglasses for all outdoor activities. In the case of welding, a visor that transmits only five-ten percent of visible light and absorbs almost all UV rays. Additionally, these glasses should have large lenses and side shields to avoid incidental light exposure. Sunglasses should always be worn, even when the sky is overcast, as UV rays can pass through clouds.