how long does sunscreen last?

Question

i was just wondering how long sunscreen protects your skin from the UVA and UVB rays before it starts wearing off. 2 hours? 3 hours? (im using spf 50. i have freckles and therefore i want to know.)

i leave the house at 6:40 everyday. but i dont put sunscreen before going out since im indoors most of the time. i do sit in a room with windows though. i put on the spf 50 sunscreen at 11 am everyday and i go home at 3 or 3:30. shud i apply it more often to prevent my freckles increasing? and if so, at what time?

also, shud i use facial scrub and exfoliate to reduce my freckles? and how many times per week? (im only 15 tho.)

Answer 1

it says on the bottle quite clearly. i.e SPF 30 = will last 30 mins of (constant, harsh) sun, SPF 15 = will only last 15 mins. And this is without water - unless u get a waterproof 'screen - it will come right off in water..

Answer 2

Um, ok, it's interesting what people will answer without any real knowledge about the topic. The SPF number on a sunscreen label tells you only how long you can stay in the sun without burning. It does not tell you the quality or amount of sun protection you are getting. An SPF of 25 means that you can stay in the sun approximately nine hours without burning while the SPF 50 allows for about 18 hours in the sun without burning. But how many places in the world have 18 hours of sunlight every day? So the extra protection is actually meaningless. In terms of how much sunlight (Ultra Violet—UV rays) gets through to the skin, both SPF 25 and SPF 50 protect nearly identically. An SPF 50 is not better than an SPF 25. If anything, it misleads lots of people into thinking they are getting stronger protection when all they are getting is unnecessary longer protection. According to the Academy of Dermatology, the sunscreen you use must be at least an SPF 15.

Answer 3

Hey, I think you're an Indian, just like me, ain't you? I'm 17 n' we've got similar routines, I can see!
Well, these days India is experiencing harsher and harsher sun-rays and the sunscreens available in the market aren't that trustworthy. If you should, use Lakme, otherwise, cover your face with a scarf; most of us girls here do it.
I find it hard to find time to apply sunscreen but a scarf in my moped's glove compartment is always handy and effective too.
As of your freckles, you need to exfoliate, that's true. I too have a few, but since I exfoliate and use a face mask alternately every week, they're under control. Since we're teens we should restrict ourselves to this only and not try any of those skin-clarity cremes.

Answer 4

Using sunscreen or exfoliating won't reduce your freckles. The bottle that you're using should say approximately how long it will stay on, and if you're just inside all day and not touching your face much, i'm sure it will probably last that long. seems a little over the top to wear sunscreen inside, but hey, to each his own.

Answer 5

This Site Might Help You.

RE:
how long does sunscreen last?
i was just wondering how long sunscreen protects your skin from the UVA and UVB rays before it starts wearing off. 2 hours? 3 hours? (im using spf 50. i have freckles and therefore i want to know.)

Answer 6

http://www.bananaboat.com/sun/spfguide.aspx

Here's a link to the banana boat web site. Personally I'm very skeptical of this chart since it doesn't take into account the intensity of the exposure but I feel it's a good start.

You really can't simply reapply the sun screen and stay in the sun indefinitely. Your skin will still feel the effects of the sun and eventually you will get burnt. Hats and other clothes that cover the skin work real well.

Exfoliating is good for the skin but wont remove freckles. Instead just appreciate the skin you have.

Answer 7

1

Answer 8

It depends on brand

Answer 9

i read that the sunblock last for 4 hours.

Answer 10

as long as the bottle it came in says it will last