Effective protection against UV rays requires broad-spectrum sunscreen and depends on the clothing worn. However, garments vary in their protective capacity. Which clothing should you favour to protect yourself from sun exposure? Read our guidance below.
T-shirt, swimwear, sweatshirt... How to choose clothing to protect against UV radiation?
Summary
Published on June 25, 2025, by Pauline, Chemical Engineer — 6 min of reading
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UV-protective clothing: allies in sun protection.
When considering sun protection, sunscreens often come to mind first. However, they represent one aspect of an effective regimen. UV-protective clothing provides a direct physical barrier against solar radiation and represents a growing strategy. It is useful when exposure is intense or prolonged, such as during a summer cycle ride or a mountain hike, where UV intensity rises by about 10% with every 1,000 metres of altitude gain. Wearing a garment designed to filter solar radiation is advisable for covering areas difficult to protect with sunscreen, such as the upper back and shoulders.
A UV-protective garment is a textile whose structure, composition or applied treatments block part of the ultraviolet rays before they reach the skin.
The performance of these garments is expressed by the UPF index (Ultraviolet Protection Factor), the textile equivalent of SPF (Sun Protection Factor) used for sunscreens. To claim UV protection under the international standard AS/NZS 4399, a garment must have a UPF of at least 15. Some fabrics exceed UPF 50. Certain items maintain protection after repeated washes, ensuring performance over many summers.
| UPF rating from 0 to 15 | UPF index from 15 to 24 | UPF index of 25–39 | UPF rating of 40 or higher |
|---|---|---|---|
| This garment does not provide UV protection. | The garment provides moderate protection and filters between 93% and 95% of UV rays. | The garment provides good protection and filters between 96% and 97.4% of UV rays. | The garment offers high protection and filters 97%–98% of UV radiation. |
The protection levels guaranteed by UPF ratings.
Good to know UPF accounts for both UVB and UVA rays, while SPF only considers erythemal UV (85 per cent UVB and 15 per cent UVA-II).
Certain populations at higher risk during sun exposure benefit from UV-protective clothing. The infants and young children, whose skin is delicate and who must avoid any direct sun exposure, people with fair skin, those with photosensitising conditions or a history or predisposition to cancer, have an increased need for photoprotection.
Schematic representation of UV rays penetrating (a) unprotected skin and (b) skin protected by UV-protective clothing.
Source: Butola B. S. et al. UV-protective clothing. Advanced Functional Textiles and Polymers (2019).
Which factors influence the sun protection of clothing?
Not all garments offer the same solar protection. When a garment bears a UV-protective label and its UPF is indicated, its ability to shield skin from the sun is clear. The same does not apply to everyday clothing, which is not labelled UV-protective but can block solar radiation. Before concluding that none of the items in your wardrobe protect against the sun, consider the following factors.
Weave density.
A fabric protects through its structure: the tighter the weave, the fewer UV rays pass through. Conversely, a lightweight garment with a loose weave, such as certain fine cotton summer shirts, allows UV rays to pass. A simple test is to hold the fabric up to the light: if you can see through it, UV rays pass through. Textiles such as polyester, wool, denim, or some heavyweight cotton weaves offer higher sun protection. For example, a dark blue pair of jeans can reach a UPF above 50 and shield the skin, while a fine white cotton t-shirt has a UPF of 7 to 10.
The colour of the garment.
Depending on its colour, a fabric does not offer the same UV protection. Dark hues, omitted in summer, absorb more UV rays than light shades such as white or yellow, which transmit more light. If you plan to spend extended time in the sun, choose a black T-shirt rather than a white one.
Tissue composition.
The fibres used and the applied treatments shape a garment’s UV performance. For example, undyed cotton contains lignins, molecules that absorb some UV. Satin silks use their reflective surface to deflect part of the sun’s rays. When the fabrics undergo factory treatment with UV absorbers, often optical agents, they acquire sun protection properties.
Humidity and garment wear.
Even a highly protective fabric can lose effectiveness under certain conditions. When wet, garments transmit more light. For example, a white T-shirt that normally provides a UPF of 7 sees its UPF rating drop to 3 when wet. Besides moisture, natural wear from fabric relaxation over time and repeated washes also reduces the UPF. When a garment is stretched, its fibres move apart and some invisible gaps to the naked eye but permeable to UV are created.
Sources
DIFFEY B. L. Sun protection with clothing. British Journal of Dermatology (2001).
DAS B. UV radiation protective clothing. The Open Textile Journal (2010).
HUANG Y. & al. Construction of anti-ultraviolet “shielding clothes” on poly(p-phenylene benzobisoxazole) fibers: metal organic framework-mediated absorption strategy. ACS Applied Materials & Interfaces (2018).
BUTOLA B. S. & al. UV protective clothing. Advanced Functional Textiles and Polymers (2019).
