UVA vs UVB Rays: What is the Difference?
What’s the difference UVA vs UVB rays? It’s an important question that doesn’t always get the attention that it deserves. So to get to the bottom of it, let’s define exactly what these rays mean.
The level of sunlight that reaches the earth’s surface is composed of two primary types of rays, both of which are harmful to the skin: Long Wave Ultraviolet A (UVA) and Short Wave Ultraviolet B (UVB). Unlike UVB rays, UVA rays penetrate deep into the skin’s thickest layer otherwise known as the dermis. However, both UVA and UVB rays can pose potential issues with unprotected exposure.
To further underscore the difference between UVA vs UVB rays, below we explain what each of these types mean and how you can minimize their effects.
What is UVB?
As the primary culprit of sunburn and skin reddening, UVB rays are responsible for damaging the more superficial epidermal layers of the skin. UVB rays contribute to the development of skin cancer and photoaging (wrinkling). And contrary to popular belief, UVB rays do not significantly penetrate glass.
The intensity of UVB varies by location, season, and time of day. Between 10 AM and 4 PM from April to October are the most potent levels of which UVB hits the U.S. However, UVB rays can still burn and damage skin year-round. This is particularly common at high altitudes or against reflective conditions such as snow and ice. Against these conditions, UVB can reflect up to 80 percent of the rays. As a result, they can make contact with skin twice.
What is UVA?
Unlike UVB rays, UVA are present with relatively equal intensity throughout all daylight hours during the year. They can also penetrate glass and clouds. UVA rays make up 95 percent of the UV radiation that reaches the our planet’s surface. Although these rays are less intense compared to UVB, UVA rays are 30 to 50 times more prevalent.
UVA penetrates the skin more deeply than UVB and are considered to play a major role in skin aging and photoaging. Until recently, most scientists were under the belief that UVA rays did not cause significant damage in areas of the epidermis (the outermost layer of the skin.). However, over the years studies have shown that UVA rays damage skin cells in the basal layer of the epidermis, where most skin cancers occur. As a result, UVA exposure can contribute to and may even initiate the occurrence of skin cancers.
Minimizing the Deleterious Effects of UVA & UVB Rays
For active lifestyles, avoiding sun exposure in its entirety is not always an option. However, you can minimize the deleterious effects of UVA and UVB by following these guidelines:
- Seek shade whenever possible, especially between the peak hours of the sun (10 AM and 4 PM.)
- Do not let your skin burn. When the skin turns pink, take this as a sign that your skin is starting to burn.
- Avoid artificial tanning, such as UV tanning booths.
- Cover up with clothing, including a brimmed hat and polarized sunglasses.
- Apply a broad spectrum sunscreen with at least a SPF of 15 before going outdoors. For extended outdoor activity, use a water-resistant sunscreen with an SPF of 30 or higher (such as SolRx’ Zinc Sunscreen Stick for Face.)
- Keep newborns and young children out of the sun. Sunscreens should be used on babies over the age of six months.
- Take time every month to examine your skin from head-to-toe.
At SolRx, the best line of defense against both UVA and UVB rays is a broad spectrum sunscreen. We’ve formulated many different products that provide this protection under some of the most extreme conditions, including 8 hours of water immersion and high-altitude, snowy conditions. See what’s in store and shop SolRx sunscreens to ensure you’re protected against both UVA and UVB.
Image by Hazar Shok