In the first two Sweep-the-Sun columns in summer 2022, we looked at the revised ISO 24444:2019 Gold standard and at the alternative methods [1, 2]. So it’s time to take another look at the progress made.
The Consortium ALT-SPF conducted the largest interlaboratory-test to date about a year ago, but the reports on the test methods involved have not yet been published [3]. Pro Memoria, the following methods were characterized against the gold standard (Table 1)…