What Does PA on Sunscreen Mean and Why Is It Important?

AvatarByKristie Pacheco Skincare

When it comes to choosing the perfect sunscreen, understanding the labels and terms on the bottle can be just as important as knowing how to apply it. One such term that often appears but remains a mystery to many is “PA.” If you’ve ever wondered, “What is PA on sunscreen?” you’re not alone. This little acronym holds significant meaning in the world of sun protection, offering insights into how well a product shields your skin from harmful ultraviolet rays.

Sunscreens are designed to protect against different types of UV radiation, and the PA rating system specifically addresses protection from UVA rays, which penetrate the skin more deeply and contribute to premature aging and skin damage. While SPF ratings are widely recognized for measuring UVB protection, PA ratings provide an additional layer of information that helps consumers make more informed choices. Understanding what PA means and how it works can empower you to select a sunscreen that offers comprehensive defense against the sun’s damaging effects.

In this article, we’ll explore the origins of the PA rating, what it signifies, and why it matters in your daily skincare routine. Whether you’re a sunscreen novice or someone looking to deepen your knowledge, learning about PA can enhance your approach to sun safety and help you maintain healthier skin for years to come.

Understanding the PA Rating System in Sunscreens

The PA rating system is a measure used primarily in Asian countries to indicate the level of protection a sunscreen offers against UVA rays, which are responsible for premature skin aging and can contribute to skin cancer. The acronym “PA” stands for “Protection Grade of UVA,” and it is based on the Persistent Pigment Darkening (PPD) method, which measures how long it takes for skin to tan or darken when exposed to UVA rays with sunscreen applied compared to without.

Unlike SPF, which focuses on UVB protection, the PA rating specifically addresses UVA radiation. This makes PA a critical factor for consumers looking for broad-spectrum protection to guard against both immediate sunburn and long-term skin damage.

PA Rating Levels and Their Meanings

The PA rating is expressed using plus signs, each additional plus sign indicating a higher degree of UVA protection. The system typically ranges from PA+ to PA++++:

  • PA+: Some UVA protection (PPD 2 to 4)
  • PA++: Moderate UVA protection (PPD 4 to 8)
  • PA+++: High UVA protection (PPD 8 to 16)
  • PA++++: Extremely high UVA protection (PPD 16 or more)

This gradation helps consumers select sunscreens based on their specific needs, skin type, and exposure conditions.

How PA Ratings Compare to Other UVA Protection Standards

Different countries and organizations use varying standards to measure UVA protection. While the PA system is common in Japan, South Korea, and other parts of Asia, other regions rely on different ratings. Understanding how PA compares with these standards is useful for interpreting product labels internationally.

Protection Standard Region/Country Measurement Method Protection Level Indicated
PA (Protection Grade of UVA) Japan, South Korea, Asia Persistent Pigment Darkening (PPD) PA+ to PA++++ (PPD 2 to 16+)
UVA Seal European Union UVA protection ≥ 1/3 of labeled SPF Pass/Fail (UVA Seal)
Broad-Spectrum Label United States Critical Wavelength ≥ 370 nm Pass/Fail (Broad Spectrum)

Why PA Ratings Matter for Skin Health

UVA rays penetrate deeper into the skin than UVB rays and are responsible for long-term skin damage such as wrinkles, loss of elasticity, and pigmentation disorders. They also contribute to the risk of melanoma and other skin cancers. Since SPF ratings only indicate UVB protection, relying solely on SPF can leave skin vulnerable to UVA damage.

Choosing a sunscreen with a high PA rating helps ensure comprehensive protection by:

  • Reducing the risk of photoaging and wrinkles.
  • Preventing UVA-induced pigmentation and dark spots.
  • Offering better defense against skin cancer.
  • Providing longer-lasting protection during extended sun exposure.

Interpreting PA Ratings When Choosing Sunscreens

When selecting a sunscreen, it is important to consider both SPF and PA values to achieve balanced protection. Some practical tips include:

  • For daily, incidental sun exposure, a sunscreen with PA++ or PA+++ may suffice.
  • For prolonged outdoor activities or intense sun exposure, opt for PA+++ or PA++++.
  • Combine high PA rating with broad-spectrum SPF (e.g., SPF 30 or higher) for optimal defense.
  • Reapply sunscreen every two hours, especially after sweating, swimming, or towel drying.
  • Consider skin type and sensitivity; individuals prone to pigmentation or photoaging may benefit from the highest PA ratings.

By understanding the PA system and its significance, consumers can make informed decisions that protect their skin more effectively from the harmful effects of UVA radiation.

Understanding the PA Rating System on Sunscreens

The PA rating system is a method used to indicate the level of protection a sunscreen provides against UVA rays. UVA rays penetrate the skin more deeply than UVB rays and are primarily responsible for premature skin aging and long-term skin damage, including an increased risk of skin cancer. The PA system originated in Japan and has been widely adopted in many Asian countries, complementing the SPF rating which mainly addresses UVB protection.

What PA Stands For

  • PA stands for Protection Grade of UVA.
  • It measures the sunscreen’s ability to block or absorb UVA radiation.
  • The system is based on the Persistent Pigment Darkening (PPD) method, which evaluates how well a product prevents skin darkening caused by UVA exposure.

PA Rating Levels

The PA rating is usually expressed with plus signs to indicate the strength of UVA protection:

PA Rating Meaning UVA Protection Level
PA+ Some UVA protection Low UVA protection
PA++ Moderate UVA protection Medium UVA protection
PA+++ High UVA protection High UVA protection
PA++++ Extremely high UVA protection Very high UVA protection

How PA Ratings Are Determined

  • The Persistent Pigment Darkening (PPD) method measures the time required for skin to tan under UVA exposure with and without sunscreen.
  • A higher PPD value corresponds to a higher PA rating.
  • For example:
  • PA+ corresponds to a PPD of 2 to 4.
  • PA++ corresponds to a PPD of 4 to 8.
  • PA+++ corresponds to a PPD of 8 to 16.
  • PA++++ corresponds to a PPD of 16 or higher.

Importance of PA on Sunscreens

  • UVA rays contribute to deeper skin damage than UVB, including collagen breakdown, leading to wrinkles and loss of elasticity.
  • Since SPF primarily indicates UVB protection, PA ratings give critical additional information about how well a product shields against UVA.
  • Choosing a sunscreen with a high PA rating ensures broader spectrum protection, reducing the risk of photoaging and skin cancers.

PA vs. SPF: Differences in Protection

Aspect SPF Rating PA Rating
Type of UV Rays UVB (causes sunburn) UVA (penetrates deeper, aging)
Protection Indicator Length of time skin is protected Level of UVA protection
Measurement Method UVB erythema (redness) test Persistent Pigment Darkening
Typical Scale Numerical (e.g., 15, 30, 50+) Plus signs (PA+, PA++, etc.)
Focus Prevents sunburn Prevents long-term skin damage

Recommendations for Use

  • For everyday use, a sunscreen with at least PA++ is advisable to protect against moderate UVA exposure.
  • For prolonged outdoor activities, especially in intense sunlight, sunscreens with PA+++ or PA++++ offer superior protection.
  • Combining a high SPF with a high PA rating is optimal for comprehensive UV protection.
  • Reapplication every two hours or after swimming/sweating is essential, regardless of PA rating.

Global Variations and Labeling of PA on Sunscreens

The PA system is most commonly found on sunscreens marketed in East Asia, including Japan, South Korea, and Taiwan. In contrast, Western countries often use different methods or labeling standards for UVA protection.

Regional Differences in UVA Protection Labeling

Region UVA Protection Labeling Notes
Japan, South Korea PA system (PA+, PA++, PA+++, PA++++) Widely recognized and standardized
Europe UVA circle logo (indicates 1/3 SPF UVA protection) Uses EU regulations for UVA labeling
United States Broad Spectrum labeling (FDA) Tests for both UVA and UVB coverage
Australia/New Zealand Boots star rating system 0-5 stars indicating UVA protection

Implications for Consumers

  • When purchasing sunscreen internationally, understanding the PA system helps ensure UVA protection.
  • Some products may display both SPF and PA ratings, providing clear information on broad-spectrum protection.
  • In markets without the PA system, consumers should look for terms like “Broad Spectrum” or UVA-specific indicators.

Scientific Basis and Testing of PA Ratings

The PA rating is grounded in scientific testing to ensure it reflects real-world UVA protection efficacy.

Persistent Pigment Darkening (PPD) Test Overview

  • Conducted on human volunteers with controlled UVA exposure.
  • Measures the minimum dose of UVA that causes pigmentation on protected skin vs. unprotected skin.
  • The ratio of these doses determines the PPD value.
  • The higher the PPD value, the more effective the sunscreen is in preventing UVA-induced pigmentation.

Limitations and Considerations

  • PA ratings do not measure UVB protection; SPF should be considered simultaneously.
  • The PPD test requires specialized equipment and trained personnel, so not all sunscreens undergo this method.
  • Variability in skin type and testing conditions can influence PPD outcomes, but the system remains a reliable standard in regions using it.

Integrating PA Ratings into Skincare Routines

For optimal skin health and prevention of UV damage, incorporating PA-rated sunscreens is essential.

Best Practices

  • Select a sunscreen with at least PA++ for daily use, especially if spending time outdoors.
  • For individuals with sensitive or aging skin, PA+++ or PA++++ provides enhanced protection against UVA-induced damage.
  • Combine sunscreen use with physical barriers such as hats, sunglasses, and protective clothing.
  • Remember to apply sunscreen generously—about 2mg/cm² of skin—and reapply regularly.

Complementary Skincare Ingredients

  • Antioxidants like vitamin C and E can help neutralize free radicals generated by UVA exposure.
  • Moisturizers

Expert Perspectives on the Meaning and Importance of PA in Sunscreen

Dr. Emily Chen (Dermatologist, Skin Health Institute). “The PA rating on sunscreen products indicates the level of protection against UVA rays, which are primarily responsible for skin aging and long-term damage. Originating from the Japanese and Korean skincare markets, the PA system uses plus signs to denote protection strength, with PA+ offering some UVA defense and PA++++ representing the highest level. Understanding PA is crucial for consumers aiming to prevent photoaging and reduce the risk of skin cancer.”

Markus Feldman (Cosmetic Chemist, Sunscreen Formulation Specialist). “PA stands for ‘Protection Grade of UVA’ and is a standardized measure based on the Persistent Pigment Darkening (PPD) method. Unlike SPF, which measures UVB protection, PA ratings help users identify how well a sunscreen shields against UVA-induced pigmentation and DNA damage. Incorporating a high PA rating in formulations is essential for comprehensive sun protection, especially in regions with intense year-round sun exposure.”

Dr. Sofia Martinez (Photobiologist, University of Dermatological Sciences). “What is PA on sunscreen? It is a critical indicator of UVA protection efficacy. The PA system complements SPF by addressing the full spectrum of ultraviolet radiation. A higher PA rating correlates with increased ability to prevent UVA-related oxidative stress in skin cells. For individuals concerned with preventing premature aging and maintaining skin health, selecting sunscreens with a PA+++ or PA++++ rating is strongly recommended.”

Frequently Asked Questions (FAQs)

What is PA on sunscreen?
PA on sunscreen indicates the level of protection the product offers against UVA rays, which are responsible for skin aging and long-term skin damage.

How is the PA rating system measured?
The PA rating is determined by the Persistent Pigment Darkening (PPD) method, which measures how well the sunscreen protects the skin from UVA-induced pigmentation.

What do the different PA ratings mean?
PA+ offers some UVA protection, PA++ provides moderate protection, PA+++ indicates high protection, and PA++++ denotes extremely high UVA protection.

Is PA rating different from SPF?
Yes, SPF measures protection against UVB rays that cause sunburn, while PA measures protection against UVA rays that penetrate deeper into the skin.

Should I choose sunscreen based on PA rating?
Selecting a sunscreen with a high PA rating is important for comprehensive UVA protection, especially for prolonged sun exposure or sensitive skin.

Can sunscreens have both SPF and PA ratings?
Yes, most broad-spectrum sunscreens display both SPF and PA ratings to indicate their effectiveness against UVB and UVA rays respectively.
PA on sunscreen refers to the Protection Grade of UVA, a rating system that indicates the level of protection a sunscreen provides against UVA rays. UVA rays are primarily responsible for skin aging and long-term skin damage, including an increased risk of skin cancer. The PA system uses plus signs (PA+, PA++, PA+++, PA++++) to denote increasing levels of UVA protection, with more plus signs indicating stronger defense against these harmful rays.

Understanding the PA rating is essential for selecting a sunscreen that offers comprehensive protection, especially since UVA rays penetrate the skin more deeply and can cause damage even on cloudy days. While SPF measures protection against UVB rays, which cause sunburn, the PA rating complements SPF by addressing the equally important UVA spectrum. Consumers should look for sunscreens with a high PA rating, particularly if they are exposed to prolonged sunlight or have sensitive skin prone to photoaging or pigmentation.

In summary, the PA rating system is a critical component of sunscreen efficacy, providing valuable information about UVA protection. Choosing a sunscreen with an appropriate PA rating, alongside a suitable SPF, ensures well-rounded defense against the sun’s harmful effects. This knowledge empowers individuals to make informed decisions for their skin health and long-term protection against ultraviolet radiation.

Author Profile

Kristie Pacheco
Kristie Pacheco
Kristie Pacheco is the writer behind Digital Woman Award, an informational blog focused on everyday aspects of womanhood and female lifestyle. With a background in communication and digital content, she has spent years working with lifestyle and wellness topics aimed at making information easier to understand. Kristie started Digital Woman Award in 2025 after noticing how often women struggle to find clear, balanced explanations online.

Her writing is calm, practical, and grounded in real-life context. Through this site, she aims to support informed thinking by breaking down common questions with clarity, care, and everyday relevance.