What is a UV t-shirt?
Legally, in Europe, to call a t-shirt "UV t-shirt", its sun protection index must be higher than UPF40. At KER SUN, we prefer UV t-shirts with a UPF50+ index to guarantee optimal protection.
Please note: UPF50+ certification is the highest certification we are allowed to state in the European Union.
Thanks to its weave and composition, UV t-shirts block UV rays. It is one of the most effective forms of protection against sun damage.
What does UPF stand for?
The ultraviolet protection factor "UPF" indicates the amount of UV rays (UVB and UVA) that a fabric blocks. For example, a UPF50+ fabric blocks more than 98% of the sun's rays, significantly reducing your risk of exposure.
To evaluate the UPF level of a fabric, it must be tested to a standard. The most common standards are the European standard (EN13758-1), the Australian and New Zealand standard (AS/NZA 4399/2017) and the American standard (AATCC 183). All three are very similar in their calculation methods.
Is a rashguard a UV t-shirt?
A rashguard is a sport shirt, mostly used for aquatic activities, made of a blend of spandex and nylon or spandex and polyester. The term rashguard refers to the fact that the swimming shirt has the ability to protect from skin rashes caused by abrasion, or from sunburn. However, if a rashguard is not certified with a UPF index, then we cannot know its true level of sun protection and there is no guarantee of a truly effective sun protection.
For a rashguard to be considered a "UV-T-shirt", it must be tested and certified at least UPF40 in European Union.
To conclude, the term "Rashguard" does not necessarily mean "UV-T-shirt".
Is a UV T-shirt suitable for use in water?
A UV t-shirt is not necessarily designed to go in the water. There are also ready-to-wear UV t-shirts to protect you in your daily life, but also sports UV t-shirts to accompany you in your sporting activities.
The latter can be made of natural or artificial fibres (cotton, viscose, lyocell...) and their UV performance will therefore decrease in the water.
Rashguard are designed to go in the water and offer optimal sun protection even when wet.