THE GREATEST RISK FOR OCULAR UV EXPOSURE IS BETWEEN 10:00 A.M. AND 2:00 P.M?
FALSE, indeed! Yes—it is accurate to suggest that direct, overhead sunlight may be extremely harmful to unprotected skin (e.g., the scalp, ears and shoulders). However, the eyes are vulnerable to the most severe UV and high-energy visible light (HEV) exposure in the morning between 8:00 a.m. and 10:00 a.m., and then again in the late afternoon between 3:00 p.m. and 6:00 p.m.
What’s the explanation? Here are several likely theories:
~When the sun is closer to the horizon, harmful UV and HEV rays are more directly in-line with the eyes.
~Many people don’t always wear sunglasses in the early morning or late afternoon, when ocular exposure is at its highest potential.
~People also are less likely to wear brimmed hats or other protective clothing that may shield the eyes during the earliest and latest times of day.
Even when wearing conventional UV-protective sunwear, anti-reflective coatings may actually increase radiation exposure from the back surface of the lens.
Bottom line—EVERYONE should wear sunglasses and protective clothing when outside during all daylight hours. But, there is a slightly heightened risk in the morning and afternoon.