We took your questions to the UPF testing lab at ARPANSA

We took your questions to the UPF testing lab at ARPANSA

7 min read
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Image: Screenshot taken from ARPANSA promotional video

Lydia TjongLydia Tjong is the Assistant Director of Ultraviolet Radiation Services at ARPANSA. We asked her your frequently asked questions about UPF testing and UPF rated clothing.


What is ARPANSA?

The Australian Radiation Protection and Nuclear Safety Agency, or ARPANSA for short, is the Australian Government's primary authority on radiation protection and nuclear safety. ARPANSA protects people and the environment from the harmful effects of radiation, including ultraviolet (UV) radiation, through research, the services they provide, and regulation of Commonwealth entities that use radiation.  

What is UPF? Why does it matter? 

UPF stands for Ultraviolet Protection Factor, which is a measure of the level of sun protection provided by clothing materials, such as fabrics, garments, and hats. It matters since over-exposure to UV radiation can cause sunburn, skin damage, and skin cancer. We cannot feel or see UV radiation. For example, UV levels can be high even on cloudy days and when the air temperature is not very high. Therefore, it is important to protect our skin with clothing materials of known UPF.  

Is there any difference between UPF testing to the Australian standard vs. other standards, such as in the USA? 

When UPF testing is done to the Australian standard, it means that the effects of the harsh Australian sun have been taken into account. Australia experiences some of the highest levels of solar UV radiation in the world. One reason is Australia's close proximity to the equator. Other factors such as the earth’s elliptical orbit and atmospheric conditions contribute to higher levels of UV radiation in the Southern Hemisphere than the Northern Hemisphere in their summer seasons. This means that UPF testing to the Australian Standard is more conservative than testing to other standards. 

Why is UPF lab testing better than holding my garment up to a light source to determine the fabric's sun safety? 

Many factors affect the UPF, including material composition, weight, tightness of the weave, color, stretch, moisture content, and finishing treatment. Holding a clothing material up to a light source helps to show how much light passes through, but this isn’t an ideal way to determine how protective a material is against the sun, because the human eye sees visible light but not UV. This is the reason why laboratory testing is needed.  

What goes into the testing process? 

Clothing materials are cut up to get a number of samples. Each sample is exposed to a UV radiation lamp that simulates the sun’s intensity around noon. The amount of UV passing through is then measured by a detector. The raw measurement data are used to calculate the UPF, taking into account the biological effects on human skin. For example, high-energy UV is more dangerous than low-energy UV, so when calculating the UPF, more weighting is placed on the high-energy UV.  

Can the UPF vary between colors?  

Most of our clothing is dyed attractive or functional colors. Many dyes absorb UV radiation, which helps reduce sun exposure. Darker colors tend to absorb more UV than lighter colors, including whites and pastels, but bright colors such as red can also substantially absorb UV rays. So yes, UPF can vary depending on the color of the material. 

What if my light and darker colored garments are both rated UPF50+? Will they protect the same? 

Garments that are rated UPF50+ provide all-day sun protection for people with the fairest of skin types, regardless of the garment colors. You should choose garments with UPF50+ if you are planning to be outdoors most of the day. 

How long does UPF protection typically last in a garment? 

UPF testing is performed on clothing materials that are in new condition. How the UPF varies with use depends on a number of factors, such as the material, finishing treatment, and adherence to care instructions. To give an example, the UPF rating of many cotton-based materials can improve over the “new condition” rating after they have been washed at least once. Shrinkage in these fabrics closes small gaps between the fibres and allows less UV radiation to pass through. However, old, threadbare or faded garments may have a lower UPF rating.  

Should I be wearing sunscreen underneath my UPF 50+ clothing? 

For UPF50+ garments, if the skin is completely covered by it, there is no need to apply sunscreen. Application of sunscreen would be of personal preference only. For garments with UPF30 or lower, there is a recommendation to apply sunscreen underneath. Bear in mind that the UPF of the garment may be reduced if the material is wet, stretched, or from the effects of normal wear or exposure to chemicals. 

All Solbari fabrics are tested and rated by ARPANSA. You can discover Solbari's sun protective range by clicking the links below:

Women UPF 50+
Men UPF 50+
Sun hats UPF 50+
Accessories UPF 50+ 
SPF 50+ Sunscreen

This blog is for information purposes only, always consult your medical professional for expert advice.

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