A comprehensive approach to evaluating and classifying sun‐protective clothing

Summary Background National standards for clothing designed to protect the wearer from the harmful effects of solar ultraviolet radiation (UVR) have been implemented in Australia/New Zealand, Europe and the U.S.A. Industry standards reflect the need to protect the skin by covering a considerable proportion of the potentially exposed body surface area (BSA) and by reducing UVR‐transmission through fabric (the Ultraviolet Protection Factor; UPF). Objectives This research aimed to develop a new index for rating sun‐protective clothing that incorporates the BSA coverage of the garment in addition to the UPF of the fabric. Methods A mannequin model was fixed to an optical bench and marked with horizontal lines at 1‐cm intervals. An algorithm (the Garment Protector Factor; GPF) was developed based on the number of lines visible on the clothed vs. unclothed mannequin and the UPF of the garment textile. This data was collected in 2015/16 and analysed in 2016. Results The GPF weights fabric UPF by BSA coverage above the minimum required by international sun‐protective clothing standards for upper‐body, lower‐body and full‐body garments. The GPF increases with BSA coverage of the garment and fabric UPF. Three nominal categories are proposed for the GPF: 0 ≤ GPF < 3 for garments that ‘meet’ minimum standards; 3 ≤ GPF < 6 for garments providing ‘good’ sun protection; and GPF ≥ 6 indicating ‘excellent’ protection. Conclusions Adoption of the proposed rating scheme should encourage manufacturers to design sun‐protective garments that exceed the minimum standard for BSA coverage, with positive implications for skin cancer prevention, consumer education and sun‐protection awareness. What's already known about this topic? National standards for clothing labelled as sun‐protective are based on the clothing fabric exceeding a minimum Ultraviolet Protection Factor (UPF). Standards vary on the minimum body surface area required to be covered. What does this study add? A new clothing classification system is introduced utilizing an easy‐to‐calculate metric that incorporates both the fabric UPF and protected body surface area. The new metric, termed the Garment Protection Factor (GPF), provides a mechanism for the fair assessment of apparel of different types and size categories aimed to encourage better sun‐protective clothing design for the prevention of skin cancer. Linked Article: Gefeller. et al. Br J Dermatol 2018; 178:835–836 Plain language summary available online