Rational determination of real‐life <scp>UV</scp> exposure across latitudes: An extended Diffey‐based model integrating behavioural factors

By converting ambient irradiance into effective received dose, this model provides a realistic framework for daily UV exposure. It complements Diffey's approach rather than replacing it, supports rational discussion on SPF and UVA-PF adequacy without prescribing individual recommendations and offers a quantitative basis for realistic product design, regulatory discussion and consumer guidance.