Sun Protective Clothing

New standards for sun protective fabrics in the United States were unveiled in January 2001. The United States now has the most stringent UV-protective clothing standards in the world! The new units for UV protection are called UPF (Ultraviolet Protection Factor). UPF is like the sun protective factor SPF used on sunscreen lotion bottles and fabrics today, in that both UPF and SPF measure sunburn protection. One difference between UPF ratings and SPF ratings is that UPF measures both UVB and UVA radiation blocked. SPF is a measurement of UVB radiation only. The new UPF fabric rating also requires that fabrics claiming to be sun protective must be prepared in the following ways before testing:

  1. Undergo 40 simulated launderings
  2. Be exposed to 100 fading units of simulated sunlight
    (equivalent to 2 years light exposure)
  3. And, if intended for swim wear, exposure to chlorinated water

The following is a comparison between the UPF and SPF ratings:

Classification Category Rating % UV Blocked
Very Good UV Protection
UPF 25, 30, 35 96.0% - 97.4%
Very Good UV Protection SPF 25, 30 96.0% - 97.4%
Excellent UV Protection UPF 40, 45, 50+ 97.5% - 98.0%
Excellent UV Protection SPF 30+ 97.5+%

Currently the new standards are voluntary, but could become mandatory in the future. In the next couple years, consumers should expect to see both UPF and SPF ratings used on clothing as the transition is made.