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Fabrics and clothing for protection against the sun
Also see Sun Protection Products for a list of companies selling fabrics and clothing.
When choosing clothing for sun protection, you want clothing to cover up as much skin as possible; thus high or turned up collars, long sleeves and long pants or skirts are a good choice. Next, you want fabrics to block or reflect as much light as possible. In general, heavier, tightly woven, dark fabrics protect better than light, loose, light fabrics. Finally, there are a couple different ways of measuring fabric sun protection:
SPF: the old fashioned Sun Protective Factor (SPF) rating which measures only UVB radiation and is used on sunscreens,
UPF, and the new ultraviolet protection factor-UPF rating which measures both UVB and UVA radiation blocked. (See Sunscreens for a deion of UVA and UVB light.)
SPF ratings of fabrics and clothing (Sun Protection Factor)
Clothing is generally a good UV blocker, although lighter fabrics that are desirable because they are cooler may not have as great a protective value as heavier fabrics such as denim, which is generally the most protective. The sun protection value of fabric is more a function of the hole size of the fabric mesh than the particular fabric type Typical summer shirt fabrics only have an SPF of 6.5. Some articles say that denim has an SPF value of 50 or more. Darker color fabrics provide greater protection from UV rays than do lighter color fabrics.
Common sense home fabric test:
A useful rule of thumb is to hold a shirt up to a strong light source such as a light bulb. If you can see images through it, it probably has an SPF value less than 15. If light gets through, but you can't really see through it, it probably has a SPF value somewhere between 15 and 50. If it completely blocks all light, it probably has an SPF value greater than 50 (e.g. heavy cotton denim).
Fabrics and clothing for protection against the sun
Also see Sun Protection Products for a list of companies selling fabrics and clothing.
When choosing clothing for sun protection, you want clothing to cover up as much skin as possible; thus high or turned up collars, long sleeves and long pants or skirts are a good choice. Next, you want fabrics to block or reflect as much light as possible. In general, heavier, tightly woven, dark fabrics protect better than light, loose, light fabrics. Finally, there are a couple different ways of measuring fabric sun protection:
SPF: the old fashioned Sun Protective Factor (SPF) rating which measures only UVB radiation and is used on sunscreens,
UPF, and the new ultraviolet protection factor-UPF rating which measures both UVB and UVA radiation blocked. (See Sunscreens for a deion of UVA and UVB light.)
SPF ratings of fabrics and clothing (Sun Protection Factor)
Clothing is generally a good UV blocker, although lighter fabrics that are desirable because they are cooler may not have as great a protective value as heavier fabrics such as denim, which is generally the most protective. The sun protection value of fabric is more a function of the hole size of the fabric mesh than the particular fabric type Typical summer shirt fabrics only have an SPF of 6.5. Some articles say that denim has an SPF value of 50 or more. Darker color fabrics provide greater protection from UV rays than do lighter color fabrics.
Common sense home fabric test:
A useful rule of thumb is to hold a shirt up to a strong light source such as a light bulb. If you can see images through it, it probably has an SPF value less than 15. If light gets through, but you can't really see through it, it probably has a SPF value somewhere between 15 and 50. If it completely blocks all light, it probably has an SPF value greater than 50 (e.g. heavy cotton denim).
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