A closer look at UV rays
Did you know that there are 3 types of ultraviolet (UV) rays?
Ultraviolet A rays (UVA)
UVA rays make up most of the sun’s natural light. They can penetrate deep into the skin and cause wrinkles and premature aging of the skin.
Ultraviolet B rays (UVB)
UVB rays are the main cause of sunburn. They are nearly 1,000 times stronger than UVA rays.
Ultraviolet C rays (short-wave radiation)
These rays never reach the earth’s surface because the atmosphere filters them out.
Fast facts about UV rays
- UV rays can get through clouds, fog and haze.
- Water, sand, concrete and especially snow reflect the sun’s rays – and make them even stronger.
- We’re exposed to more UV rays as the protective layer of ozone around the earth becomes thinner.
- The main source of UV radiation is the sun, but indoor tanning beds and sun lamps are also sources.
The UV Index is used to measure the strength of UV rays that reach the earth’s surface. In Canada between April and September, the UV Index can be 3 or more from 11 a.m. to 3 p.m., even when it’s cloudy. On these days, you need to be extra careful to protect your skin. Here’s how to find your UV Index.