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Article: Understanding the PA Rating System for sunscreen

Woman applying Brush On Block to face

Understanding the PA Rating System for sunscreen

Brush On Block is proud to announce that all of our Mineral Powder Sunscreens and all three shades of our Protective Lip Oil are rated PA+++. But what does that mean?

When you shop for sunscreen, the SPF, or Sun Protection Factor, is probably the first thing you look for. Doctors recommend that everyone wear at least an SPF 30 every day and recommend that the container say Broad Spectrum on the front. This is because SPF, while very important, needs to be backed up by some assurance that you are being protected from both UVA and UVB rays.

UVB rays, the ones that cause sunburn, and can lead to skin cancers, are the ones you worry most about when you are out enjoying a day at the beach or by the pool. They are strongest in the summer. The SPF number on your sunscreen refers to the extent to which the product protects your skin from those UVB rays. In the US, only when the words Broad Spectrum are present on the front of the product, do you have any assurance that the product also protects you from UVA rays.

UVA rays penetrate deeper into the skin, and while they cause skin tanning (or darkening), which some people seek, they also cause signs of photoaging like dark spots and wrinkles, and like UVB can lead to skin cancer. (Note to those that like to tan. There is no such thing as safe tanning, darkened skin is damaged skin. The only safe “tan” comes from a bottle.)

Broad Spectrum sunscreen protects you from both UVA and UVB rays, and products must meet FDA testing requirements to bear these words on the label. But as a consumer, it can be difficult to figure out exactly how much UVA protection your product provides.

Enter the PA system. Developed in Japan, and widely in Asia, the PA system was developed to accurately measure the UVA protection of sunscreens. To determine a PA rating, which goes from PA+ to PA++++, sunscreens are tested to determine a PPD, or Persistent Pigment Darkening factor. Then that factor is converted to the PA grading system, which is easy to understand.

The PA symbols on some sunscreens mean

            PA+        provides some UVA protection

            PA++      provides moderate UVA protection

            PA+++    provides high UVA protection

            PA++++  provides extremely high UVA protection

The PA rating system allows you to see how much UVA protection your sunscreen provides, so that you can best judge your coverage.

As always, it bears mentioning that no matter what the SPF or PA rating of your product, ALL sunscreens must be reapplied every 2 hours when in the sun. If your sunscreen does not say either “Water Resistant 40 Minutes” or “Water Resistant 80 Minutes,” you should assume that it is not water resistant. And when a number of minutes are given, you should reapply after that amount of time if you have been in and out of the water. Towel drying or wiping means that sunscreen should be immediately reapplied.

The PA Rating System is another tool in your arsenal to help you select the best products to protect your skin. Find the combination of UVA, UVB and Water Resistance, but always keep in mind that the BEST sunscreen is the one that you will wear!