Sun protection

[Paul the Headblader]

Hello.
I know there are much topics about protection against the sun, but I want you to know my case in detail.
I've first shaved my head in october, so I didn't really get to meet the sun while I was bald ( harsh winter in Romania).
I never used any protection against the sun. I barely used a hat or something during the last summer.
So, about sunscreen lotions..do they really protect? Even if I'm not wearing a hat/beanie or so? ( in RO there's like 100 - 113 F degrees).
If I'm not supposed to wear a hat if I use the sunscreen lotion, like how long does it last? Can I go out a day long ( not necesarily to stay in the sun all day long) without worrying about it?
Thanks.
Please complete the list if I've forgotten something.
I guess I'll owe you one more time

[BaldHDbiker]

Sunscreens really do work. You need to reapply every couple of hours especially with the temps you will experience. You'll be sweating and it'll run  off.

[Laser Man]

Sunscreens work, but you still have to be careful.  Two people can wear the same sunscreen and burn at different times because of their sensitivity to the sun is different.   Also, no sunscreen is really sweat and waterproof, so you have to reapply them regularly.

[Paul the Headblader]

thank you guys.
one more question: when should I apply it? I mean, it depends on the temperatures?
Like: when it's hotter than 68 F, or so?

[Baldstu]

Suggest you lookat the weather and check the sun intensity , you can get burned in a cloudy sky , wind is worse .but ifin doubt use a screen , remember to rub it in well , it looks really naff if you av white cream on your noggin

[Paul the Headblader]

Suggest you lookat the weather and check the sun intensity , you can get burned in a cloudy sky , wind is worse .but ifin doubt use a screen , remember to rub it in well , it looks really naff if you av white cream on your noggin

thanks!

[D.A.L.U.I.]

one more question: when should I apply it? I mean, it depends on the temperatures?
Like: when it's hotter than 68 F, or so?

The temperature has absolutely nothing to do with sunscreen, nothing at all.  It's the sun, you can get burned in freezing weather, and hazy days can be more dangerous than full sun.  It's more dangerous when you can't feel the heat on your scalp. 

[Laser Man]

one more question: when should I apply it? I mean, it depends on the temperatures?
Like: when it's hotter than 68 F, or so?

The temperature has absolutely nothing to do with sunscreen, nothing at all.  It's the sun, you can get burned in freezing weather, and hazy days can be more dangerous than full sun.  It's more dangerous when you can't feel the heat on your scalp. 

Absolutely true.  One of the worst sunburns I got was on a mild early April day with a little breeze.  Was outside walking around all day and by mid afternoon had a bad burn.

[Paul the Headblader]

Thank you guys!