New ISO Methods to Measure SPF of Sun Products

In December 2024, the International Organisation for Standardisation (ISO) published two new methods for measuring the Sun Protection Factor (SPF) of cosmetic products. One is the Double Plate in vitro Method (DPM), the other is the Hybrid Diffuse Reflectance Spectroscopy (HDRS).

This webinar explains the technicalities of these new ISO methods to measure the SPF of cosmetic products.

This session will cover the below topics.

The presentations from this webinar are available at the above links for each session. The written Q&A from this webinar can be downloaded at this link.

Measuring the SPF of Sun Protection Products

The UK and EU Cosmetics Regulations do not prescribe specific testing methods to measure the Sun Protection Factor (SPF) of sunscreen products. However, the EU Commission Recommendation on sun products, which also applies in the UK, provides a list of recommended test methods to measure the SPF of sun protection products. These are test methods published by the International Organisation for Standardisation (ISO). The Recommendation states that preference should be given to in vitro testing methods delivering equivalent results, as in vivo methods raise ethical concerns. CTPA encourages members to follow this position.

Furthermore, Cosmetics Europe Recommendation No.26 on the use of alternative methods to the in vivo SPF testing method, ISO 24444.2019, recommends that preference should now be given to the new non-invasive reference methods, ISO 23675.2024 (double plate method) and ISO 23698.2024 (HDRS method). The CE recommendation clarifies that sunscreens already tested using the in vivo method are not expected to undergo retesting with the new alternative methods. However, if retesting is conducted, the recommendation offers guidance on how to address possible outcomes of the results.