Symbol Definitions
Weak
: Exposure to UVA/B rays is minimal and
least harmful, but some protection is still neces-
sary. Most people can stay in the sun during
peak hours (10 am–4 pm) up to an hour.
Medium
: Low risk of harm from exposure. Fair
skin might burn in less than 20 minutes. Use a
sunscreen with a minimum of Sun Protection
Factor (SPF) 15, cover exposed skin, and wear a
hat and sunglasses.
Strong
: High risk of harm. Fair skin may burn
in less than 10 minutes. Use minimum SPF 15
sunscreen cover exposed skin, wear a hat and
sunglasses, and seek shade when outside.
Very Strong
: UVA/B rays are most damaging at
this level. Fair skin may burn in less than 5 min-
utes. Avoid going outside between peak hours
(10 am–4 pm) if possible. If you are outside, try
to avoid direct sunlight, use minimum SPF 15,
cover exposed skin, wear a hat and sunglasses,
and seek shade.
Source: Adapted from Environmental Protection Agency
EPA 430-K-98-004, March ‘98
