This second edition of the ISO 24444:2019 standard, published in December 2019, cancels and replaces the first edition (ISO 24444:2010), which has been technically revised. As presented on the ISO webstore preview mode, the main changes compared to the previous edition are as follows:
- The definition of the minimal erythema response (MED) criteria has been revised.
- The choice of eligible test subjects is now based solely on individual typology angle (ITA°) with a requirement for the average ITA° for the test panel to be within the range 41° to 55°, with a minimum of three subjects within two of the three ITA° ranges.
- The ITA° is used to define the range of unprotected MED doses for the provisional or the test day unprotected MED determination (if no provisional MEDu determination is made).
- Three new reference standard sunscreens have been validated and added to the method to validate SPF test panels for products with SPF equal to 25 or higher (P5, P6 and P8).
- New test methods are provided to determine the uniformity of the beam of both large and small beam size solar simulators. A requirement for uniformity greater than or equal to 90 % has been added.
- Sunscreen application procedures have been described in greater detail.
- An informative Annex F has been added with photographic examples of erythema responses with guidelines for grading.
- The reporting tables in Annex G) and the requirements in Clause 11 have modified to provide more complete information on the results of the testing.
- The bibliography has been updated.