17-1366

ultraviolet protection factor [FUVP]

measurement of the protective quality of a fabric sample against solar ultraviolet radiation, determined by in-vitro testing

Unit: 1

NOTE 1 For in-vitro testing the erythemal irradiance measured by a detector with the fabric sample-under-test in place is compared to the erythemal irradiance measured with no fabric present, where the light source is typically a solar simulator. This is expressed in the following equation:

        

where

ser(λ) is the erythema spectral weighting function;

Eλ is the spectral irradiance;

τ(λ) is the measured spectral transmittance of the item;

Δλ is the bandwidth;

λ is the wavelength.

NOTE 2 The ultraviolet hazard spectral weighting function, s(λ), has been substituted for ser(λ) in special instances. If so used, the ultraviolet protection factor, FUVP, must be noted as FUVP [s(λ)-weighted].

Abbreviation: "UPF"

Theme by Danetsoft and Danang Probo Sayekti inspired by Maksimer