Ocular exposure to occupational non-ionising radiation in professional pilots

Adrian Carl Chorley
2015
Research evidence supports the link between long term exposure to ultraviolet (UV) and the blue light hazard with ocular damage including cataract and macular degeneration. Population studies to determine the prevalence of these conditions in pilots are inconclusive. It is known that UV and blue light intensities increase with altitude. The aim of this research was to investigate whether professional pilots are adequately protected from UV and short wavelength light during flight. Informed by
more » ... ight. Informed by the results of 22 semi-structured interviews, a questionnaire exploring the eye protection habits of professional pilots was developed and completed by 2,967 participants. The results showed a wide variation in pilot use of sunglasses, uncovered barriers preventing sunglass use and showed a high level of dissatisfaction regarding standard aircraft sun protection systems. In flight irradiance measurements were captured during 6 airline and 4 helicopter flights. No measurable UVB was found. UVA exposure was highly reliant on the transmission properties of the aircraft windshield. Further ground measurements on 15 aircraft showed the majority had windshields which transmit significant levels of UVA into the cockpit. This can cause the ocular dose for the unprotected eye to exceed international recommended exposure limits within ½ hour of flight. Older aircraft generally had superior UVA blocking windshields. Although calculated retinal exposure to blue light hazard during flight fell well within international recommended limits, the mean radiance was 4.1 times higher at altitude. The effect of this over a flying career remains uncertain. Filter transmittance measurements were taken from 34 pilot sunglasses and 20 new sunglasses typically used by pilots. All sunglasses filters measured offered sufficient protection from UVA in flight and ensured an attenuation of the blue light hazard to levels equivalent to those at ground level without protection. A series of practical recommendations are made to pilot [...]
doi:10.18744/pub.001962 fatcat:adwt7c45j5etppglpt2pkr5gsm