5.5UV-Transmittance

The UV-transmittance of glazing is the fraction of the incident solar radiation transmitted by the glazing in the 300 nm to 380 nm range (UV-B range from 300 nm to 315 nm and UV-A range from 315 nm to 380 nm). The UV-transmittance $\tau_{UV}$ is calculated as follows:

where

$S_{\lambda}$ = relative spectral distribution of UV radiation;

$\tau (\lambda) =$ spectral transmittance of the glazing; and

$\Delta\lambda$ and the integration procedure are the same as 5.1.11.4 except that the data points shall be chosen at the wavelength given in Table 12.

This average extends over the defined UV-portion of the solar spectrum. It may not be correlated with solar radiation damage of materials and skin.