The EPA has devised general guidelines as far as what to do to protect oneself from overexposure to UV radiation. These are shown in the table below:
Exposure Category: Minimal
UV Index: 0, 1, 2
Protective Actions: Apply skin protection factor (SPF) 15 sun screen.
Exposure Category: Low
UV Index: 3, 4
Protective Actions: SPF 15 & protective clothing (hat).
Exposure Category: Moderate
UV Index: 5, 6
Protective Actions: SPF 15, protective clothing and UV-A&B sun glasses.
Exposure Category: High
UV Index: 7, 8, 9
Protective Actions: SPF 15, protective clothing, UV-A&B sun glasses, and attempt to avoided the sun between 10am and 4pm.
Exposure Category: Very High
UV Index: 10+
Protective Actions: SPF 15, protective clothing, UV-A&B sun glasses and attempt to avoid the sun.