Sun Protection Sample PFA Test

Protheragen-ING's Sun Protection Sample PFA Test assesses a product's ability to protect against UVA (ultraviolet radiation A) rays, while the corresponding SPF test evaluates its protective effect against UVB (ultraviolet radiation B) rays.

Understanding of UVA and UVB

Although both UVB and UVA rays originate from sunlight, they vary in terms of wavelength, penetration depth, and the harm they inflict on the skin.

Fig. 1 Differences between UVB (Ultraviolet Radiation B) and UVA (Ultraviolet Radiation A) rays.

• UVB rays have shorter wavelengths and reach only the skin's epidermis. They can cause short-term problems such as sunburn, tanning, and erythema, as well as long-term damage such as DNA cell damage.
• UVA rays possess longer wavelengths, penetrating the skin's dermis layer. They induce short-term effects such as melanin deposition, skin darkening, and the formation of spots. UVA rays can also damage cell DNA, and collagen, accelerate skin aging, and potentially lead to severe conditions such as skin cancer.

Sunscreen Test Standards

In the United States, the FDA mandates that the PFA (persistent pigment darkening in response to UVA) value of sunscreen must be at least 1/3 of the SPF (sun protection factor) value to be labeled as "broad-spectrum", signifying its ability to shield against both UVA and UVB rays.

The ISO 24443:2012 Cosmetics standard is an international guideline outlining methods for assessing the UVA protection capacity of sunscreen products.

Sunscreen is applied to the subject's skin, and the minimum ultraviolet radiation dose or the shortest radiation time required to induce slight skin darkening is observed 2 to 4 hours after exposure. By calculating the ratio of the MPPD (Minimum Persistent Pigment Darkening) needed for skin protected by sunscreen cosmetics to that required for unprotected skin, the UVA protection effectiveness is determined.

Cosmetics Europe (European Trade Association for the cosmetics and personal care industry) has introduced guidelines proposing the COLIPA method, which utilizes PMMA (polymethyl methacrylate), an acrylic material known for its high transparency. While the COLIPA method offers stability, simplicity, and safety, it may not always correlate perfectly with human outcomes. Combining testing methods can provide a more comprehensive evaluation of product efficacy.

Services Process

Demand Analysis

Our experts conduct an initial assessment to understand the specific testing requirements to provide guidance on which method is best with the product's intended use and regional regulations.

For global markets, we ensure compliance with relevant international standards, such as ISO 24443 and COLIPA guidelines.

Testing Execution

Our skilled professionals perform the selected tests, ensuring accurate and reliable results.

Data Analysis and Reporting

A comprehensive analysis report is generated, which includes detailed test results and interpretations.

Follow-up Support

Protheragen-ING remains available for any additional questions or assistance that clients may require.

Additional Test Items

In addition to the above tests, Protheragen-ING offers a qualitative and quantitative analysis of various common sunscreen ingredients. These ingredients include avobenzone, octinoxate, octisalate, octocrylene, zinc oxide, titanium dioxide, and more.

If you have specific sunscreen ingredients or services in mind that are not listed here, please don't hesitate to contact us. We will arrange for our professionals to provide tailored strategies to meet your specific needs.