Films can deliver varying degrees of light protection based mostly on the UV absorbers and pigments
used in either the base film of a multi-layer structure or that of the mono-layer film. Many brand
owners and engineers will default to the information contained in USP to determine a
requirement. A film with both a “food approved” UV absorber combined with an amber pigment will
typically meet USP and prevent the percentage of light transmission from exceeding 10% for
wavelengths between 290 and 450nm.