All about Sun Protection Ratings

UPF stands "for Ultraviolet Protection Factor."

UPF is a measure of total ultraviolet radiation (UV) blocked, both UVA and UVB. Exposure to UV rays can cause not only sunburn, but also lasting skin damage, such as premature skin aging and skin cancer. Additionally, UV rays can also cause eye disorders, such as cataracts.

Testing

While sunscreen is a trusted precaution against sun-related illness, sun protective apparel offers an even more effective shield from harmful UV rays. Because some apparel is better at blocking more of these UV rays than others, a rating system was established (see history below) so that conscious consumers can more easily make purchases based on the amount of sun protection a garment provides.

For a garment to achieve a UPF rating, it must undergo a series of tests based on the standards set forth by the American Association of Textile Chemists and Colorists (AATCC) and the American Society for Testing and Materials (ASTM). Within these tests, each garment is tested for its initial UV protection and then for the UV protection it offers after two years of consumer use (to achieve this evaluation, the garment is laundered 40 times and exposed to 100 fading units of UV radiation to simulate the wear and use of over a two-year period). The latter test determines the UPF rating for the product.

UPF rated garments often display a hangtag with the designated rating for that garment. The following chart offers an explanation of what these ratings mean:

Excellent

• UPF Range: 40 - 50+
• UPF Values Allowed on Labels: 40, 45, 50, 50+
• Approximate % UV Blocked: 97.5% - 98.0%

Very Good

• UPF Range: 25 - 39
• UPF Values Allowed on Labels: 25, 30, and 35
• Approximate % UV Blocked: 96.0% - 97.45

Good

• UPF Range: 15-24
• UPF Values Allowed on Labels: 15 and 20
• Approximate % UV Blocked: 93.3% - 95.8%

History

In 1996, the Australian Radiation Agency developed a UPF rating system to proactively reduce the astounding percentage of Australians who were being diagnosed with skin cancer and other sun-related illnesses each year. This UPF rating system was then adopted and enhanced for the US by the American Association of Textiles, Chemists, and Colorists (AATCC; 2000) and ASTM International (ASTM; 2003) organizations. These Standards are the most stringent UV protection standards for fabrics in the world.