Sunscreens Flashcards
1
Q
What is SPF
A
lab measure of sunscreen efficacy and is defined as amount of UB radiation required to produce a sunburn on protected skin relative to that of unprotected skin
2
Q
What is the critical wavelength
A
it measures the breadth of UV-A absorbance by a sunscreen and must be used in combination w/ the SPF value to provide a complete assessment of UV protection
3
Q
what is substantivity?
A
a sunscreen’s ability to remain effective under adverse conditions such as exposure to water and sweat
4
Q
what is stability?
A
important for long-lasting protection w/ continuous exposure to UV light in particular to prevent photodegradation