ISO 16217:2020

It is entitled “Cosmetics — Sun protection test methods — Water immersion procedure for determining water resistance.”
This document specifies a procedure of water immersion for the in vivo determination of the water resistance of sunscreen products.
It is applicable to products intended to be placed in contact with human skin including any component able to absorb, reflect or scatter UV rays and which, in addition, are designed to be less readily removed from the skin by water and/or during water immersion. It is intended to be read in conjunction with ISO 24444.

ISO 18861:2020

This second standard is entitled “Cosmetics — Sun protection test methods — Percentage of water resistance.”
describes the procedure for water resistant percentage calculation, based on water immersion procedure described in ISO 16217, which is the ratio between before and after bath SPF.
The SPF measurement procedure is that described by ISO 24444.

Both standards are on sale on the ISO website at a price of 58 Swiss francs.

For further information
• See the ISO 16217:2020 Standard
• See the ISO 18861:2020 Standard