What is % UVR Block ?

What is % UVR Block ?

Summary

Percentage UVR block relates to the performance of the shade cloth that reflect or absorb incident Ultra Violet Radiation (UVR) within the 290nm to 400nm range of the spectrum.

What is % UVR Block ?
Percentage UVR block relates to the performance of the shade cloth that reflect or absorb incident Ultra Violet Radiation (UVR) within the 290nm to 400nm range of the spectrum. This includes UV-A radiation (315nm to 400nm) and UV-B radiation (280nm to 315nm). For example, Aquatic Blue shade cloth has a 94.2% UVR block which means that in laboratory test conditions ~94% of incident Ultra Violet Radiation (290nm to 400nm) is absorbed or reflected by the shade cloth.
Research worldwide has shown that mainly UV-B, andto a lesser extent UV-A, radiation is harmful to humans and often causessunburn.  Additionally, chronic exposure to UVR has shown a relationshipto increased rates of skin cancer.  Therefore, the percentage of UVR blockis an important factor when selecting shade cloth designed to protect people.
UVR Block varies between different brands and typesshade cloth. This heavily depends on the construction and more importantly thequality of the UV stabiliser in the material of the shade cloth.  Because the shade cloth actually absorbs someof the UVR, a shade cloth with less UV stabiliser may break-down, or fail insunlight faster than other fabrics.