Ultraviolet radiation penetrating vehicle glass: a field based comparativestudy

The solar UV transmitted through automobile glass was measured in the field in two cars using a spectroradiometer. The two cars were identical except that one of the cars had all of the windows (except the windshield) tinted. The measured spectral erythemal UV on a horizontal plane with the windows fully closed was reduced in the tinted car by a factor of 42 when compared with the erythemal UV measured in the untinted car. The ambient UVA irradia nces at various locations within four different makes of car and a tractor were also measured with a broad band UVA handheld meter. The average normal ized daily UVA exposure (measured with a broad band UVA meter) was 1.3 time s higher in a large family sedan when compared with that in a small hatchba ck and the UVA exposure in a car with tinted windows was 3.8 times less tha n in a similar untinted car.