Overview
EN ISO 16217:2021 - Cosmetics: Sun protection test methods - Water immersion procedure for determining water resistance (ISO 16217:2020) is a CEN-adopted European version of the ISO standard that defines an in vivo water immersion procedure to determine the water resistance of sunscreen products. It applies to topical products and any component intended to absorb, reflect or scatter UV radiation and formulated to resist removal by water. The standard is intended to be read in conjunction with ISO 24444 (in vivo determination of SPF).
Key topics and requirements
- Scope: Specifies an in vivo water immersion challenge inserted into the ISO 24444 SPF test sequence for products designed to be water‑resistant.
- Test sequence: Sunscreen application → dry‑down (per ISO 24444) → water immersion in a simulated swim device → drying → UV exposure and SPF measurement using ISO 24444 procedures.
- Test subjects: Human volunteers enrolled per ISO 24444 criteria; minimum 10 subjects for water resistance studies. Informed written consent specific to water immersion testing is required.
- SPF metrics defined:
- Individual water resistance SPF (SPFiwr): SPF measured on each subject after immersion.
- Post‑water immersion SPF: Arithmetic mean of valid individual water resistance SPF values (expressed to one decimal by truncation).
- Water resistance SPF (SPFwr): Group mean of SPFiwr values.
- Apparatus and annexes: Includes normative annexes covering a simulated swim test device design (Annex A), standardized water requirements (Annex B), a standard reference sunscreen (Annex C), and product positioning on subjects (Annex D).
- Validation and statistics: Clauses address procedural validation, calculation methods, and statistical criteria for reporting water resistance SPF (see Clause 8).
Applications
- Claim substantiation: Provide robust, standardized evidence for “water‑resistant” or “very water‑resistant” sunscreen claims.
- Product development: Compare formulations and optimize water‑resistant properties during R&D.
- Quality control and regulatory compliance: Support labeling and compliance with national/regional cosmetic regulations and industry best practices.
- Independent test laboratories: Standardizes in vivo protocols to produce reproducible, comparable results across labs.
Who should use this standard
- Cosmetic manufacturers and formulators targeting water‑resistant sunscreen claims
- Contract testing laboratories and clinical testing facilities
- Regulatory affairs and compliance teams verifying labeling claims
- Product development and quality assurance teams assessing SPF performance after water exposure
Related standards
- ISO 24444:2019 - Cosmetics - Sun protection test methods - In vivo determination of the sun protection factor (mandatory companion standard for SPF measurement)
Keywords: EN ISO 16217:2021, ISO 16217:2020, water resistance, sunscreen testing, water immersion procedure, sun protection test methods, SPF, ISO 24444, simulated swim test device.
