It doesn't have it's own value but should be treated the exact same way you treat your skin in the sun. The sunlight can damage it so make sure to wear a hat to protect it and your skin.
There are number of cosmetics products for removing suntan . SPF is the sun protecting factor more the SPF value more effective is the cream. Generally sun protecting factor value ranges from 20 to 30.
spf stands for sun protection factor
Jojoba oil has an SPF of 4.
It has an SPF of 15 (I know because I have it)
An SPF of about 30
Neutrogena makes a spf 30 lipgloss.
Yes, Neutrogena makes it, it is called " Spectrum+ Advanced sunblock lotion SPF 100+." As matter of fact, I have seen SPF 110!!!
It was probably SPF 30 because that blocks 96.7% of UVB rays. SPF 50 blocks 98% so you aren't really getting that much more protection than the SPF 30. Neutrogena has a SPF 100 but it really isn't necessary because as I said, SPF 30 is already blocking a significant amount, and SPF 50 doesn't even make that much more of a difference. Just for your information, SPF 100 blocks 99% of UVB rays so it REALLY doesn't do much more than SPF 50.
Currently Beach Bum Tanning Lotions do not contain SPF's. SPF's protect you skin from harmful rays.
"The Sun Protection Factor (SPF) displayed on the sunscreen label ranges from 2 to as high as 50 and refers to the product's ability to screen or block out the sun's harmful rays. For example, if you use a sunscreen with an SPF 15, you can be in the sun 15 times longer that you can without sunscreen before burning. Consumers need to be aware that SPF protection does not increase proportionally with an increased SPF number. While an SPF of 2 will absorb 50% of ultraviolet radiation, an SPF of 15 absorbs 93% and an SPF of 34 absorbs 97%." from http://www.melanomafoundation.org/prevention/facts.htm
The best way to protect your hair from the sun is by wearing a hat or by applying a leave in conditioner as a barrier between the sun and your hair. Although there are shampoos which claim to contain SPF, they are not completely effective being that the shampoo simply rinses out in the shower!
No. SPF 30 lets in 1/30 of burning UV rays, while SPF 50 lets in 1/50. Adding the two together is pointless and would not result in high levels of skin protection.