Abstinence from being on the water where the most UV radiation exposure occurs
When the sun is low in the sky : 8-10:00 a.m. and 2-4:00 p.m.
UV radiation is reflected ...water up to 100%...sand up to 25%
More than 40% of UV exposure occurs when you are not in direct sunlight
UV exposure is cumulative and its damage is often irreversible
Inside vision like a well lit office is 500 lux
Outside vision the noon sun emits up to 100,000 lux..that is over 200X
So also protect your eyes