Most of us probably know by now the importance of using sunscreen. But many of us are also confused about how to choose a sunscreen that gives you the right protection. Read on to learn more about sunscreen ratings and how to choose a suitable one for your skin.
Ultraviolet radiation from the sun
The sun emits ultraviolet radiation in three bands, namely UVA (315-400 nm), UVB (280-315 nm) and UVC (100-280 nm). The ozone layer prevents almost all UVC rays and up to 90% of UVB rays from reaching the earth’s surface. Thus 94% of UV radiation reaching the earth’s surface consists of UVA rays and only 6% consists of UVB rays.
Choosing and using a sunscreen is important for protecting us from the sun’s dangerous UV rays. When we select a sunscreen, we need to assess its sun protection factor, or SPF rating, which measures a sunscreen’s ability to filter UVB rays, and its PA rating for UVA protection.
What is SPF?
A sunscreen’s SPF, or “sun protection factor,” refers to its protection against the sun’s UV rays. It measures the time it would take for a person to start getting red if he or she was not wearing sunscreen.
In general, it takes about 10 to 20 minutes without sunscreen for a person’s skin to start burning. An SPF 15 product would prevent skin from burning for 15 times longer – which means for about 150 to 300 minutes, or about 2.5 to five hours. However, that doesn’t mean full protection against the sun for that five hours. We need to reapply sunscreen every two to four hours, as sunscreen can rub off or get washed off in the water.
It is also commonly misunderstood that “SPF 30” is twice as good as “SPF 15”. However, this representation is not accurate. A sunscreen with an SPF 15 blocks about 93 percent of the sun’s dangerous rays. SPF 30 products block about 97 percent of such rays, and SPF 50 sunscreen shields against about 98 percent of rays, and so forth.
Protection Grade of UVA Rays
Have you ever noticed PA+++ rating in the sunscreens mentioned along with the SPF level?
PA refers to the Protection Grade against UVA rays. This Japanese measurement ranking is based on the Persistent Pigment Darkening (PPD) reaction reading at 2 to 4 hours of sun exposure. The protective grade of sunscreen is often labelled as PA+, PA++, PA+++; with the more plus sign, the more protection from UVA rays.
In the United States and European Union, the term Broad-Spectrum Protection is on the label to indicate that the product has passed testing to show it protects from both UVA and UVB damage.
A good sunscreen to consider would be Radium’s Self Defence SPF 50+/PA+++ Sun Protection Lotion. With the following sunscreen active ingredients, it provides broad spectrum protection from UVA and UVB rays that can age and burn your skin.
|Physical Sunscreen||Chemical Sunscreen||Protect Against|
|Titanium Dioxide||Ethylhexyl Methoxycinnamate||UVB|
|Isoamyl p-Methoxycinnamate||UVAII + UVB|
|Bis-Ethylhexyloxyphenol Methoxyphenyl Triazine||UVA + UVB|
|Diethylamino Hydroxybenzoyl Hexyl Benzoate||UVA|
It glides on very easily with a light touch without leaving behind a whitish cast or feeling greasy.
It also has this light, sweet scent derived from the botanical extracts of Centella Asiatica, Chamomile, Licorice and Rosemary. Also, using it feels like an extra moisturizer to one’s skin, because it is paraben free and formulated with Niacinamide and Hyaluronic Acid to soothe and hydrate the skin at the same time.
So, what sunscreen should I buy?
The US Skin Cancer Foundation recommends a water-resistant, broad-spectrum sunscreen with an SPF of 30 or higher for any extended outdoor activity. Sunscreens with SPF higher than 50 do not offer significant greater protection from UVB rays. We recommend a SPF50 sunscreen with PA+++ for overall protection from UVA and UVB.
Regardless of the SPF, though, it’s important to apply 2 tablespoons (a shot glass worth) to the exposed areas of the face and body, with a 20- cents sized dollop to the face alone. This should be carried out at least half an hour before venturing outside and reapplying it every two hours or immediately after swimming or sweating.
However, sunscreen is just one essential part of a sun protection strategy that should also include seeking shelter in shaded areas, covering up with long- sleeved clothing, including wide-brimmed hats and UV-blocking sunglasses, and taking oral sunblock.