Breadcrumb
- Home
- Search Health Topics
- Ultraviolet Rays From The Sun
Ultraviolet Rays From the Sun
Topic Contents
Overview
The sunlight that reaches the earth has ultraviolet A and ultraviolet B (UVA and UVB) rays. These ultraviolet rays are the main causes of damage to the skin from the sun. UVA and UVB rays affect the skin's sensitivity to sun exposure in different ways.
UVA
- Can pass through window glass
- Is not affected by a change in altitude or weather
- Is present all day and every day of the year
- Penetrates deep into skin layers
- Is 20 times more abundant than UVB rays
- Causes long-term skin damage
UVB
- Cannot pass through window glass
- Causes sunburn
- Causes tanning
- Helps the body make vitamin D
- Is more intense:
- During the middle of the day
- In the summer
- At high altitudes and near the equator
- Can cause skin cancer and cataracts
Most sunburn and skin cancer can be prevented. Use the following tips to protect your skin.
Avoid exposure to the sun
- Try to spend less time in the sun from 11 in the morning to 3 in the afternoon. Find shade if you need to be outdoors.
- Wear clothing that blocks the sun. This can be a wide-brimmed hat that covers your neck, ears, eyes, and scalp. It can also include loose-fitting, light-coloured, tightly-woven clothes that cover your arms and legs.
- Wear sunglasses that block UV rays.
Use sunscreen
- Always wear sunscreen on exposed skin. Make sure to use a broad-spectrum sunscreen that has a sun protection factor (SPF) of 30 or higher. Use it every day, even when it is cloudy.
- Apply sunscreen at least 30 minutes before you go out in the sun. Put on more every 2 to 3 hours while you are in the sun and after you sweat a lot or swim.
- Take extra care to protect your skin when you're near water, at higher elevations, or in tropical climates.
- Use a broad-spectrum lip balm or cream that has SPF of 30 to protect your lips from getting sunburned.
Related Information
Credits
Adaptation Date: 9/19/2023
Adapted By: HealthLink BC
Adaptation Reviewed By: HealthLink BC
Adaptation Date: 9/19/2023
Adapted By: HealthLink BC
Adaptation Reviewed By: HealthLink BC
This information does not replace the advice of a doctor. Healthwise, Incorporated disclaims any warranty or liability for your use of this information. Your use of this information means that you agree to the Terms of Use and Privacy Policy. Learn how we develop our content.
Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated.
HealthLinkBC Files
HealthLinkBC Files are easy-to-understand fact sheets on a range of public health and safety topics including disease prevention and immunizations.
Find Services and Resources
If you are looking for health services in your community, you can use the HealthLinkBC Directory to find hospitals, clinics, and other resources.