Overview
EN ISO 24442:2022 (Corrected version 2024-10) - "Cosmetics - Sun protection test methods - In vivo determination of sunscreen UVA protection" - is a CEN-endorsed international standard that specifies an in vivo method to determine the UVA protection factor (UVAPF) of sunscreen products. It applies to cosmetic products containing components that absorb, reflect or scatter ultraviolet (UV) rays and intended for contact with human skin. The standard provides a quantitative basis for evaluating sunscreen performance against UVA radiation from solar ultraviolet rays.
Key topics and technical requirements
The standard defines procedural and technical elements required for reliable in vivo UVA testing:
- Test subjects: selection criteria, skin colour typing, age restrictions, ethics/consent and limits on repeat participation.
- Apparatus and UV source: requirements for UV solar simulators, beam uniformity, spectral quality and radiometric/spectroradiometric monitoring.
- Reference materials: use of reference sunscreen formulations and standard controls for calibration and comparison.
- Test procedure: site preparation, product application (amount, mode of delivery, uniformity), drying time, exposure sub-sites and incremental UV dosing.
- Response assessment: methods for measuring minimal persistent pigment darkening doses (MPPDD), grading scales, timing of assessments and rejection/test-failure criteria.
- Calculation and statistics: computation of individual and product UVAPF, statistical criteria for validation and reporting requirements.
- Quality assurance: maintenance and monitoring of the solar simulator output and data validation procedures.
Applications and practical value
EN ISO 24442 is used to:
- Quantify UVA protection claims on sunscreen labels.
- Support product development by comparing UVA performance across formulations and delivery systems.
- Provide objective evidence for regulatory compliance, marketing claims and safety/risk assessments.
- Calibrate and validate laboratory UV solar simulators and test procedures.
Practical benefits include reproducible comparison of products, standardized reporting formats, and alignment with regulatory expectations for sun protection cosmetics.
Who should use this standard
- Cosmetic formulators and R&D teams developing sunscreen products.
- Independent testing laboratories and clinical research organizations conducting in vivo sun protection tests.
- Regulatory affairs professionals verifying product claims and compliance.
- Quality assurance teams responsible for test method validation and equipment calibration.
Related standards
- Works alongside other sun protection standards (for example, in vivo SPF testing methods) to provide a complete assessment of UVB and UVA protection. Users often pair EN ISO 24442 with SPF test standards for comprehensive sun protection evaluation.
Keywords: EN ISO 24442:2022, UVAPF, UVA protection, in vivo determination, sunscreen testing, sun protection test methods, cosmetic sunscreen, UV solar simulator.