Contribution to the radiation protection for sunglasses standards.

Literature establishes safe limits on the exposure of the eyes to ultraviolet radiation, for the range of 180-400 nm, including spectrally weighted and the total ultraviolet radiant exposure. Most standards for sunglasses protection only require ultraviolet protection in the spectral range of 280-380 nm to ensure the limits for effective spectrally weighted radiant exposure. Calculations of these limits were performed for 27 Brazilian state capitals, and they led to a change in the upper UVA limit to 400 nm on the 2013 review of the Brazilian standard. Moreover, because the sunlight irradiance in Brazil is quite high, integration over the 280- to 400-nm range yields an ultraviolet radiant exposure that is an average of 49% greater than that for the 280- to 380-nm range. These conclusions suggest revision on the standards.