UPF: It’s like Sunscreen SPF Ratings for your clothes

Hi There,

Did you know that you’re hit with over two times the UV radiation in the summer versus the winter? If you’re in the northern hemisphere, the sun’s rays are about to be at their strongest, and you should be prepared for that increase in UV radiation.

 Proper sun protection is critical for minimizing UV exposure and preventing premature aging, sunburns and risk of melanoma. As Mary Schmich once famously said: "Wear sunscreen." But there's another piece to the puzzle that's easy to overlook - your choice of clothing.

Today, I’ll shine a light on how they’re built to keep your skin safe all season long.

UV Light is part of the electromagnetic spectrum 

Electromagnetic waves are all around us. We see a certain range in the form of visible light (Red to Violet) with our own eyes, while low energy ranges like Infrared can be seen with a thermal camera, and the high energy range can sometimes be seen with an X-ray machine.  

The Ultraviolet (UV) range is very high energy light; where it isn’t visible to our eyes, prolonged exposure can cause our skin to burn and our DNA to mutate, leading to conditions like melanoma.

Light can bounce off and penetrate through materials differently

When light rays from the sun hit a fabric’s surface, they will either be absorbed, reflect or penetrate through. (Fun fact: the combination of light rays absorbed and reflected are what our eyes perceive as the fabric’s color!)

Different materials reflect UV light better than others

Fibers like polyester, nylon and wool are much more effective than cotton, linen and viscose at reflecting UV light due to their chemical structure (one of the many reasons we use these materials prominently across our product line).

Pace Poplin’s Primeflex polyester yarn (the same used in our Kinetic collection) is particularly good at blocking and absorbing UV rays, due to the structure of its carbon rings:

UPF is the rating of how well fabric reflects UV light
In the same way that SPF ("Skin Protection Factor") measures a sunscreen’s efficacy, UPF ("Ultraviolet Protection Factor") represents the proportion of UV rays that reflect vs penetrate a fabric.

A common white cotton t-shirt would typically score a 5 UPF rating (meaning 1/5 of rays permeate the fabric); by comparison, Pace Poplin achieves a 50+ UPF rating in testing: only 1/50 rays permeate the fabric, effectively reflecting 98% of UV light. (For context, UPF 15-24 Ratings are considered “Good,” 25-49 Ratings are considered “Very Good,” and 50+ Ratings are considered “Excellent.”)

Another fun fact: using a separate Japanese UV Cutting Standard (JIS ASNZ 4399), we’ve actually certified it to reflect above 99.9% of UV light - the highest rating classification for a fabric!

UV protection is critical, especially in the summer when the sun's rays are much stronger (due to our angle of inclination to the sun), and in dry environments where there's less humidity to refract and absorb the high energy UV wavelengths. Sunscreen will always be a no-brainer, but as you look for work and travel clothing this summer, be sure to look for that UPF rating!

Stay curious,

- Gihan