You mean all clothing doesn't block out the sun?
July 18, 2018 1:14 PM Subscribe
What is the deal with UPF clothing? I expect that when I'm wearing a regular, normal shirt that I won't get sunburned through it. Yet now I'm seeing there's special clothing that says "SPF 50" and stuff on it. What's that mean? Isn't a regular t-shirt just about SPF infinity?
Best answer: Clothes have no SPF - their sun protection is measured by UPF.
When it comes to sun protection, I trust australians:
In 1990, after discussions with the Cancer Council Victoria (CCV) regarding how much ultraviolet radiation (UVR) protection was provided by clothing, the CCV purchased a number of items of summer beach wear and sent them for testing to the Australian Radiation Laboratory (later renamed ARPANSA, the Australian Radiation Protection and Nuclear Safety Agency). The test results were surprising, with only a few of the garments achieving a Protection Factor (PF) against UVR greater than 15. This was somewhat comparable to a sun protection factor (SPF) of 15 on sunscreen (at that time the maximum SPF in the Australian sun- screen standards).
Solar UVR levels in parts of Australia often reach extreme UV Index levels in summer,1,2 and the clothing ideally should have had PFs of at least 40-50 for adequate all-day protection of people with fair skin. The low PF levels found on the tested garments inspired a testing program to seek fabrics and materials providing proper sun protection that could be wholeheartedly recommended to the general public, outdoor workers, and schoolchildren in summer.
basically not all fabrics are the same, they are woven of different materials and in different densities in such a way that some allow more UV rays through than others.
Looks like synthetics are better than cotton - "a thin white cotton T-shirt, which has a UPF of about 5, allowing 1/5th of the sun’s UVR to pass through—even more when wet."
https://www.skincancer.org/publications/the-melanoma-letter/summer-2012-vol-30-no-2/clothing
posted by Exceptional_Hubris at 1:20 PM on July 18, 2018 [14 favorites]
When it comes to sun protection, I trust australians:
In 1990, after discussions with the Cancer Council Victoria (CCV) regarding how much ultraviolet radiation (UVR) protection was provided by clothing, the CCV purchased a number of items of summer beach wear and sent them for testing to the Australian Radiation Laboratory (later renamed ARPANSA, the Australian Radiation Protection and Nuclear Safety Agency). The test results were surprising, with only a few of the garments achieving a Protection Factor (PF) against UVR greater than 15. This was somewhat comparable to a sun protection factor (SPF) of 15 on sunscreen (at that time the maximum SPF in the Australian sun- screen standards).
Solar UVR levels in parts of Australia often reach extreme UV Index levels in summer,1,2 and the clothing ideally should have had PFs of at least 40-50 for adequate all-day protection of people with fair skin. The low PF levels found on the tested garments inspired a testing program to seek fabrics and materials providing proper sun protection that could be wholeheartedly recommended to the general public, outdoor workers, and schoolchildren in summer.
basically not all fabrics are the same, they are woven of different materials and in different densities in such a way that some allow more UV rays through than others.
Looks like synthetics are better than cotton - "a thin white cotton T-shirt, which has a UPF of about 5, allowing 1/5th of the sun’s UVR to pass through—even more when wet."
https://www.skincancer.org/publications/the-melanoma-letter/summer-2012-vol-30-no-2/clothing
posted by Exceptional_Hubris at 1:20 PM on July 18, 2018 [14 favorites]
The rule of thumb I have in my head from somewhere is that a regular cotton jersey-knit t-shirt has an SPF of about 15. This seems corroborated by the best answer to this StackExchange question: a white t-shirt has an SPF of about 4, and a blue t-shirt has an SPF of about 18.
posted by The Minotaur at 1:20 PM on July 18, 2018 [1 favorite]
posted by The Minotaur at 1:20 PM on July 18, 2018 [1 favorite]
Best answer: While clothes can protect you from the sun, different weaves, fabrics, colors, all have an effect on how much uv rays pass through to your skin (i.e. a silk fabric you can see through will protect you less than a heavy denim, for example).
"UPF clothing" is clothing that's been tested to see how much UV rays can pass through it and how much protection it can offer - that isn't to say your non-rated clothing won't be able to protect you, but this is an easy marker to have an assurance for specific sun protection.
posted by Karaage at 1:21 PM on July 18, 2018 [4 favorites]
"UPF clothing" is clothing that's been tested to see how much UV rays can pass through it and how much protection it can offer - that isn't to say your non-rated clothing won't be able to protect you, but this is an easy marker to have an assurance for specific sun protection.
posted by Karaage at 1:21 PM on July 18, 2018 [4 favorites]
Hi yes, I've been sunburned through clothes. It was a really light breathable shirt, you know, the weight of material you'd wear when it's fucking hot out. It was several hours outdoors though. (The only safe thing is to never go outside.)
posted by phunniemee at 1:21 PM on July 18, 2018 [5 favorites]
posted by phunniemee at 1:21 PM on July 18, 2018 [5 favorites]
From my limited knowledge of the subject from working for a clothing manufacturer (with a strong outdoor focus) If you are a wearer of men's clothing this is less of an issue and probably something you've not noticed in your life as the weave and weight of most men's clothes blocks a fair amount of sunlight. (when dry) Women's clothes however can routinely let through a lot of light and therefore allow sunburns. Children's clothing as well.
So UPF started being something to advertise on clothes. Once you're putting it on your women's and kids outdoor wear than it's weird not to include on the menswear line as well.
Another reason people tend not to notice is, people tend not to be in direct strong sun for as long while wearing clothes as when swimming, sunning etc. We made a lot of gear for mountain biking and had to be sure our cloth sourcing could block a lot of sun because people would get large faint sunburns otherwise.
posted by French Fry at 1:26 PM on July 18, 2018 [2 favorites]
So UPF started being something to advertise on clothes. Once you're putting it on your women's and kids outdoor wear than it's weird not to include on the menswear line as well.
Another reason people tend not to notice is, people tend not to be in direct strong sun for as long while wearing clothes as when swimming, sunning etc. We made a lot of gear for mountain biking and had to be sure our cloth sourcing could block a lot of sun because people would get large faint sunburns otherwise.
posted by French Fry at 1:26 PM on July 18, 2018 [2 favorites]
As a member of the human subtype "People Who Glow In The Dark," I have absolutely sunburned through a regular T-shirt! Before UPF on clothes became common, my go-to was a tightly-woven linen shirt, as they block most sun but are still pretty breathable.
I've never really had a problem with my legs, but I totally can get sunburned on my shoulders and upper back in a regular T-shirt.
posted by Eyebrows McGee at 1:33 PM on July 18, 2018
I've never really had a problem with my legs, but I totally can get sunburned on my shoulders and upper back in a regular T-shirt.
posted by Eyebrows McGee at 1:33 PM on July 18, 2018
Australian here - yep, getting sunburned through clothing is a thing. Damn UV rays.
posted by kitten magic at 1:33 PM on July 18, 2018
posted by kitten magic at 1:33 PM on July 18, 2018
You can totally burn through your clothes in Texas.
posted by I'm Not Even Supposed To Be Here Today! at 1:36 PM on July 18, 2018
posted by I'm Not Even Supposed To Be Here Today! at 1:36 PM on July 18, 2018
Some people also need to limit cumulative exposure due to pre-existing risk factors or conditions, and getting a tan/burn isn't necessarily a good indicator of damage.
posted by GenderNullPointerException at 1:39 PM on July 18, 2018 [4 favorites]
posted by GenderNullPointerException at 1:39 PM on July 18, 2018 [4 favorites]
If you remember the news several years ago about night vision camcorders seeing through some seemingly opaque clothes in the near infrared band, clothes UV transparency also varies widely, so to be certain of what you are getting - buy something rated, otherwise you can't know.
posted by TheAdamist at 1:43 PM on July 18, 2018
posted by TheAdamist at 1:43 PM on July 18, 2018
It's worth noting that most people can spend about 15 minutes even in the brightest sun without any ill effects (it might even be good for you), and that UV protection factor is a multiple. So you could be out there for almost 4 hours (.25 hours * 15 = 3.75 hours) and only get as much exposure as you would in 15 minutes with no protection. So a typical person might need a factor of 30 to protect themselves from all-day sun, which is higher than your typical t-shirt would provide.
posted by wnissen at 2:21 PM on July 18, 2018 [2 favorites]
posted by wnissen at 2:21 PM on July 18, 2018 [2 favorites]
Chemicals and dyes that are effective at absorbing UV light can be added to enhance UPF.
posted by Iris Gambol at 2:33 PM on July 18, 2018 [1 favorite]
posted by Iris Gambol at 2:33 PM on July 18, 2018 [1 favorite]
I buy brand name UPF clothes that have zinc and other metals woven into the threads that make up the cloth; wear them most days all day (I’m in Florida) and am usually only burned on my face from the albedo rfkection if the sand or asphalt. Have to take vitamin d to make up the lack but I get ill, not just tan or burnt from direct sun exposure.
posted by tilde at 3:08 PM on July 18, 2018 [2 favorites]
posted by tilde at 3:08 PM on July 18, 2018 [2 favorites]
A medication I takes makes me super UV sensitive (like I'll easily burn thru a car window and a long sleeve cotton dress shirt; I have to put a sun screen on when travelling west in full sun for even a moderate time). The UPF 50 stuff I buy is way more breathable than a heavy weight tight weave shirt would be. When it's 37 degrees out (in the shade) this becomes important.
posted by Mitheral at 9:34 PM on July 18, 2018 [1 favorite]
posted by Mitheral at 9:34 PM on July 18, 2018 [1 favorite]
Can people please share links to the UPF clothing they find effective? I am searching for a UPF shirt that is the summertime equivalent of a plaid flannel 90s shirt, and a hat that is very breathable but protects my ears and neck.
posted by rebent at 10:11 AM on July 19, 2018
posted by rebent at 10:11 AM on July 19, 2018
The UPF 50 stuff I buy is way more breathable
Yes I’m in a cotton hoodie and pants and shirt all day that’s just like tee shirt material.
I generally buy coolibar brand off of their site or on eBay.
I went on vacation to the north east heatwave and was hot, sweating through their long sleeved shirts and pants and hoodies layered but didn’t burn (some clothing when you sweat through you burn through)
posted by tilde at 12:21 PM on July 19, 2018
Response by poster: Update: I seem to have gotten a sunburn on my forehead while wearing a UPF 50 baseball cap in Florida on Sunday. So now I have a little more firsthand experience of this. Thank you!
posted by chrchr at 12:33 PM on January 16, 2019
posted by chrchr at 12:33 PM on January 16, 2019
Yup. Reflected up at you from the ground. Albedo is a sneaky brat.
posted by tilde at 3:05 PM on January 17, 2019
posted by tilde at 3:05 PM on January 17, 2019
This thread is closed to new comments.
posted by greermahoney at 1:16 PM on July 18, 2018 [2 favorites]