Overview
SIST EN ISO 23698:2025 is an international standard developed by CEN and ISO, specifying a non-invasive test method for objectively measuring sunscreen efficacy. Utilizing diffuse reflectance spectroscopy (DRS), this standard outlines the procedure for determining sun protection factor (SPF), UVA protection factor (UVA-PF), and critical wavelength (CW) for sunscreen products. This method allows for reliable UV protection assessment of emulsions and single-phase sunscreen formulations without requiring biological responses, making it a significant advancement in the evaluation of cosmetic products designed for sun protection.
By enabling accurate measurement of absolute spectral absorbance characteristics on human skin, this standard supports claims about sunscreen product performance with greater efficiency and ethical integrity compared to traditional in vivo methods.
Key Topics
- Diffuse Reflectance Spectroscopy (DRS): An optical technique used to assess UV absorbance and transmission properties of sunscreen applied to the skin, without the need for invasive biological endpoints.
- Hybrid UV Absorbance Measurement: Combines in vitro UVB and in vivo UVA evaluations to provide a full spectral assessment of sunscreen effectiveness.
- SPF and UVA-PF Calculation: Specifies how to estimate both SPF and UVA-PF using hybrid spectral data, in correlation with traditional reference methods.
- Critical Wavelength (CW): Measures product effectiveness across the UV spectrum by calculating the wavelength below which 90% of the total area under the absorbance curve lies.
- Scope Limitations: The method applies to emulsions and single-phase products, with no validation for powder-based sunscreens.
Applications
SIST EN ISO 23698:2025 is essential for:
- Cosmetic Laboratories: Enables non-invasive, ethical evaluation of sunscreen efficacy, supporting safety and efficacy claims during product development.
- Quality Control: Provides objective and reproducible methods for manufacturers to validate the UV protection levels of creams, lotions, gels, and similar sunscreen formulations.
- Regulatory Compliance: Assists manufacturers in meeting regulatory requirements for product labelling, claims substantiation, and market access in regions adhering to CEN and ISO cosmetic standards.
- Research & Development: Facilitates the comparison of sunscreen performance against established metrics like SPF and UVA-PF, helping innovate more effective sun protection solutions without the need for test subject exposure to harmful UV radiation.
The hybrid methodology supports faster time-to-market and higher consumer confidence by avoiding ethical concerns associated with in vivo testing, reducing costs, and improving throughput in routine sunscreen testing.
Related Standards
For comprehensive sunscreen evaluation and compatibility within the international regulatory landscape, organizations should consider the following reference standards:
- ISO 24444: In vivo determination of sun protection factor (SPF)
- ISO 24442: In vivo UVA protection factor (UVA-PF) testing
- ISO 24443: In vitro determination of UVA protection
- ISO/IEC Directives Parts 1 & 2: Guidelines for international standardization processes
SIST EN ISO 23698:2025 aligns with these standards by providing an alternative, non-invasive efficacy assessment method, thereby ensuring interoperability and scientific rigor in sunscreen product evaluation.
Keywords: sunscreen efficacy, diffuse reflectance spectroscopy, SPF measurement, UVA protection factor, critical wavelength, cosmetic standards, non-invasive sunscreen testing, EN ISO 23698, UV absorption, sunscreen assessment, in vitro testing, in vivo testing alternatives.
