Originally Posted by arch
The windscreen has to allow 75% ambient light through, the front side (pass&driver) have to allow 70% through.
At least I think it's that way around, luckily there is little reminder in our "tint man" kit.
Surprisingly, I've never gone to one of these tint shops that actually possessed a calibrated light meter, so how they sell "legal tints" is beyond me.
Tinting is a film which is tested at the factory - so providing it is not applied to pre-tinted glass it is consistent for light penetration.
These can be tested in factory conditions.
Not like the average policemans "assessment"
JJ