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Name: Unknown
Status: other
Age: 50s
Location: N/A
Country: N/A
Date: 1999-2001

Can a person get a tan while wearing a t-shirt or sitting in the shade? In other words, does the sun have an effect on the skin, while either of these two conditions exist?

Thankyou all for your help!!

It all depends on the amount of exposure to UV. If you are getting direct or indirect UV it will stimulate a response by melanocytes to produce more melanin.



One does not get a tan if he or she in the shade where the sunlight is blocked, for example, by the roof of a house. In order to get a tan, one needs to be exposed to direct sunlight. What toasts the body (also called tanning) is the ultraviolet (UV) part of sunlight radiation. This is not the visible part of sun's radiation. One can get a tan with a cloud cover overhead because UV radiation can get through some obstacles (clouds in this case). Clothing generally blocks UV radiation, that is why one wears a hat under the sun to protect head and face against radiation. I am not sure but guess that it may be possible to design clothing that let at least some UV get through.


Having received many sunburns, I feel qualified to answer your questions. Nowadays "they" try to tell us that clothing does not protect us from all the sun's damaging rays, and that it is thus necessary to wear sunscreen even under clothing. Well, I have been sunburned even through SPF 30 sunscreen many times, but never, not once have I been sunburned through clothing. So a T-shirt probably provides adequate sun protection, unless it is really threadbare. Of course, a T-shirt will do nothing for exposed arms.

It IS quite possible to get a sunburn while sitting in the shade or on a cloudy day. Like blue light, ultraviolet scatters off the atmosphere, and can reach you even if you are in the shade. Basically, if you can see the blue sky, UV can reach you.

The actual protection you get from a sunscreen depends on the concentration of its chemical that absorbs UV, how effectively it absorbs UV, how thick a layer of the stuff you have on your skin, and how easily it washes, wears, or sweats off. The sunscreens with higher SPF factors either have higher concentrations of UV-absorbing chemicals, or they have more effective UV-absorbers. There is no theoretical maximum value for SPF of a sunscreen.

Richard E. Barrans Jr., Ph.D.
Assistant Director
PG Research Foundation, Darien, Illinois

I can add on thing to the above; UV rays can reflect off of water and other reflective surfaces and as a kid, I got a terrific sunburn once and I was not exposed to direct sunlight for most of the outting. I have light skin and I'm a redhead. This topic has always been a problem for me.


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