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Flying an Airplane for an Hour Exposes Pilots to as Much Radiation as a Tanning Bed

Airplane windshields allow UV radiation to enter the cockpit, giving pilots a dose similar to dangerous levels found in tanning beds.

The daily commute for airline pilots could be the equivalent of riding to work in a tanning bed, suggests a new study. Airplane windshields can block some ultraviolet (UV) radiation found in sunlight, but a significant amount passes directly into the cockpit. This puts the crew at risk of developing melanoma, which is the most serious form of skin cancer.

In the study, published in JAMA Dermatology, researchers from the University of California, San Francisco, compared the level of UV radiation in the cockpit of a general aviation turboprop airplane with the dose produced by a standard tanning bed.

Almost an Hour of Flying Equals 20 Minutes of Tanning
The researchers took measurements in a plane at several elevations in San Jose, California, and Las Vegas, Nevada. While the plane's windshield blocked most of the UV-B radiation, it allowed UV-A radiation, which is the same type produced by the tanning bed tested, to pass through.

"Pilots flying for 56.6 minutes at 30,000 feet receive the same amount of UV-A [cancer-causing] effective radiation as that from a 20-minute tanning bed session," the authors write in the paper.

Most commercial aircraft fly at this altitude, where the level of UV radiation is double that found at ground level. UV radiation reaching the cockpit can also increase when the plane flies over thick cloud cover or snow fields, which can reflect up to 85 percent of the UV radiation.

The greater UV-A radiation exposure in the cockpit results from the design of the airplane's windshield. Tests have shown that plastic and glass windshields can block most of the UV-B radiation. However, up to 54 percent of UV-A radiation is able to get through the windshields, with plastic blocking more of this type.

Strong Link Between UV Rays and Melanoma
The link between UV-A radiation and melanoma is well established. According to the American Academy of Dermatology, one in 50 Americans will develop melanoma in their lifetime. Excessive exposure to UV radiation is a preventable cause of melanoma. People who live closer to the equator, where the sun is more intense, and those who use tanning beds are at an increased risk.

Skin Cancer
In previous research, published in JAMA Dermatology, an analysis of 19 studies showed that pilots are twice as likely as the general population to develop melanoma and 42 percent more likely to die from it.

Additional research has found that this increased risk exists even when taking into account the pilots' other sun exposure, including their history of sunburns, use of tanning beds, and numbers of sunny vacations.

The new study, however, is the first one to directly test the level of UV radiation that pilots are exposed to in the cockpit. Because only one plane was tested, though, the researchers suggest future studies be conducted on more types of aircraft. This could establish safety guidelines that would limit UV exposure for pilots.

"We believe that better UV protection on aircraft windshields is necessary to offer cabin crew a hazard-free work environment," the authors write. "We strongly recommend the use of sunscreens and periodical skin checks for pilots and cabin crew."