It’s too sunny! Will my sun umbrella “break”? This “factor” is the key →

Sun umbrellas are indispensable in summer. However, an umbrella with a UPF (Ultraviolet Protection Factor) value is not necessarily a sun umbrella and may not be able to effectively protect against the sun at all.

The larger the UPF value, the better the sun protection effect, but when buying a sun umbrella, you don't necessarily have to look for a "super large" UPF value.

Don’t be confused, just understand the standards!

What kind of ultraviolet rays does a sun umbrella protect against?

According to different bands, ultraviolet rays are mainly divided into three categories: UVA , UVB and UVC .

UVC is intercepted and absorbed by the ozone layer, and only UVA and UVB remain that can reach us.

UVB can damage the surface of human skin and cause sunburn.

UVA can damage the human dermis and cause tanning.

To protect against the sun, you need to protect against both UVA and UVB rays.

How to judge the protective effect of sun umbrellas?

The protective effect of a sun umbrella against UVA and UVB depends on the ultraviolet protection factor - UPF .

The higher the UPF value, the more UV rays are blocked and the better the protection.

For example, a UPF value of 40 means that 1/40 of the UV rays can pass through, and 1-1/40=39/40=97.5% of the UV rays are blocked;

A UPF value of 50 means that 1/50 of the ultraviolet rays can pass through, and 1-1/50=49/50=98% of the ultraviolet rays are blocked.

In addition to UPF, you sometimes also see T (UVA) AV. The lower the value, the lower the UVA transmittance and the better the protection effect .

What kind of sun umbrella is a real "anti-ultraviolet product"?

GB/T23147-2018 "Sunny Umbrella" and GB/T18830-2009 "Evaluation of UV Protection Performance of Textiles" stipulate that when UPF>40 and T (UVA)AV<5%, it can be called "UV protection product".

Those "sun umbrellas" with a nominal UPF>30 are not UV protection products at all!

UPF value marked as "very large" may not be compliant!

Since the larger the UPF value, the better the protection, then when buying it, just make sure the UPF is as high as possible, preferably several thousand?

Of course not! According to the standard, there are only two ways to label the UPF value of UV protection products: UPF40+ and UPF50+ (T (UVA) AV does not need to be labeled). When UPF>50, the sun protection effect does not differ much, and even higher values ​​can only be labeled as UPF50+.

Therefore, other UPF labeling methods (such as UPF2000) for UV protection products other than "UPF40+" and "UPF50+" are likely to be misleading and are actually non-compliant. Don't be "fooled" by the huge numbers when purchasing!