UPF clothing testing explained

2 min read

The responsible Australian Government Agency for UPF clothing testing is the Australian Radiation Protection and Nuclear Safety Agency (also known as ARPANSA).

ARPANSA have been conducting UPF clothing testing since 1990.

The ARPANSA UPF clothing testing is performed according to Australian Standard AS/NZS4399.The ARPANSA testing service is also NATA accredited. NATA independently governs laboratory testing in Australia.

The ARPANSA test involves measuring the transmission of ultraviolet (UV) light which passes through the test fabric. This test is undertaken using a calibrated ultraviolet transmission analyser on at least four fabric samples.

The AS/NZS4399 standard stipulates that UVA and UVB radiation passing through the test fabric is reported as transmittance. The transmittance scale is from 0 to 1. Transmittance is then converted to transmission by multiplying the result by 100 to give a percentage.

UVA and UVB radiation is measured in the region of 290 to 315 nanometre and 315 to 400 nanometre wavelength respectively.

The UPF result for each fabric sample is calculated.

The individual UPF values for each fabric sample are then averaged to determine the mean UPF.

The standard deviation and standard error is calculated.

The standard deviation indicates how much variation in UPF rating there is across the surface of the material. The standard error is the standard deviation adjusted for the number of fabric samples analysed.

The standard error is then subtracted from the mean UPF.

This UPF value is rounded down to the nearest multiple of five to determine the reported UPF clothing rating. One effect of this is that sample fabrics need to achieve a calculated UPF value of 55 or higher to achieve a UPF of 50+.

The rated UPF range is from 15 to 50 and 50+. UPF 50+ is the maximum UPF rating achievable.

The UPF rating also determines the protection category assigned to the material.

The protection category descriptions are good protection (which includes UPF ratings of 15 and 20), very good protection (which includes UPF ratings of 25, 30 and 35) and excellent protection (which includes UPF ratings of 40, 45, 50 and 50+).

Solbari Sun Protection offers an award-winning range of UPF 50+ sun protective clothing, broad brim sun hats, UV arm sleeves and sun umbrellas.

You can find out more about Solbari's certified UPF50+ sun protective range by clicking the links below:
Women UPF50+
Men UPF50+
Sun hats UPF50+
Accessories UPF50+

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