Originally Posted by PKI
It was my understanding that glass as a material blocks UV.
Quote from a Google search - There are 3 types of ultraviolet radiation, but only two reach the earth's surface. These are UVA and UVB. UVC is filtered out by the ozone layer. UVA mostly causes skin ageing and research has now shown that it is also likely to cause skin cancer. UVB causes redness and sunburn and is a major risk factor for all types of skin cancer. Most glass used for windows blocks UVB but not UVA. This means that although glass might reduce the risk of sunburn, it does not prevent long term damage from UVA.
Guess it does not block as much as I thought. Pat
Correct. The window specifically has to have particles in the glass to reflect UVA. I got expensive 3M Crystalline window tint put on all my car windows for that purpose.
I'll post my Airstream window UV transmittance numbers after I test them with a meter. Not looking forward to putting on more tint if it blocks little!