Determination if a product is water resistant or very water resistant.
21 C.F.R. § 352.76
in effectEffective: 2024-07-01The general testing procedures in § 352.72 shall be used as part of the following tests, except where modified in this section. An indoor fresh water pool, whirlpool, and/or jacuzzi maintained at 23 to 32 °C shall be used in these testing procedures. Fresh water is clean drinking water that meets the standards in 40 CFR part 141. The pool and air temperature and the relative humidity shall be recorded.
(a) Procedure for testing the water resistance of a sunscreen product. For sunscreen products making the claim of “water resistant,” the label SPF shall be the label SPF value determined after 40 minutes of water immersion using the following procedure for the water resistance test:
(1) Apply sunscreen product (followed by the waiting period after application of the sunscreen product indicated on the product labeling).
(2) 20 minutes moderate activity in water.
(3) 20-minute rest period (do not towel test sites).
(4) 20 minutes moderate activity in water.
(5) Conclude water test (air dry test sites without toweling).
(6) Begin solar simulator exposure to test site areas as described in § 352.73.
(b) Procedure for testing a very water resistant sunscreen product. For sunscreen products making the claim of “very water resistant,” the label SPF shall be the label SPF value determined after 80 minutes of water immersion using the following procedure for the very water resistant test:
(1) Apply sunscreen product (followed by the waiting period after application of the sunscreen product indicated on the product labeling).
(2) 20 minutes moderate activity in water.
(3) 20-minute rest period (do not towel test sites).
(4) 20 minutes moderate activity in water.
(5) 20-minute rest period (do not towel test sites).
(6) 20 minutes moderate activity in water.
(7) 20-minute rest period (do not towel test sites).
(8) 20 minutes moderate activity in water.
(9) Conclude water test (air dry test sites without toweling).
(10) Begin solar simulator exposure to test site areas as described in § 352.73.
Source: eCFRURL: https://www.ecfr.gov/api/versioner/v1/full/2024-07-01/title-21.xmlFetched: 7/26/2026