100
This is what a nurse teaches patient about decreasing risk of sun damage to the skin....
wear sun protective clothes, SPF 15 or more, Avoid sun exposure between 10 and 3; water/snow /high altitudes
Water-resistant sunscreen NOT water-proof
Use hats, umbrellas/parasols, etc.
Avoid PABA sunscreens
Drugs that cause photosensitivity: see table 24-2