Updated: Mar 8, 2020
1. Sun Damage to Skin
Going out in the sun without enough sun protection will increase your risk of sun damage also known as photo damage.
There are two forms of sun damage:
1) Chronic photo damage, which causes facial appearance change, such as the fine and coarse wrinkles.
2) Acute sun damage begins as sunburn – painful, long-lasting and very harmful to the skin’s overall health.
2. Understanding UV Radiation
Most skin cancers are caused by excess exposure to ultraviolet (UV) radiation from the sun.
In New Zealand, UV radiation levels are particularly high from September to April. It is important to be Sun Smart during these times.
The sun sends out different types of radiation:
sunlight (you can see and feel as heat)
infrared radiation (you can feel as heat)
UV radiation (you can’t see or feel)
Caution needs to be taken in cool and cloudy weather throughout the season.
When it’s cool it means there’s less infrared radiation but not necessarily less UV radiation. You can still get sunburn on cool and cloudy days known as windburn.
Types of UV radiation
UV radiation is invisible and a longer wavelength than visible light. It’s considered by wavelength into UVB, UVC, and UBA being the longest.
· UVA penetrates the skin most deeply, it causes tanning, skin ageing and DNA (cell) damage.
· UVB stimulates vitamin D production in the skin. It also causes damage to superficial epidermal layer of the skin causing sunburn. It is the major cause of Non Melanoma Skin Cancers (NMSCs). UVB does not pass through glass.
· UVC doesn’t typically penetrate past the epidermis. Ozone in the atmosphere absorbs all the UVC from the sun, however workers may be exposed to UVC in laboratories or when arc welding for example.
3. Penetration of UV radiation into skin:
Here is a good example of a 69-year-old man who drove a delivery truck for 28 years. You can see it shows damaged skin on the left side of his face, versus the right side.