Prolonged sunlight exposure in swimming athletes can cause various changes in the skin; among them is sunburn. The use of sunscreen can reduce sunburn effectively. However, various types of physical activity that can trigger sweating, friction, washing with water, or sun exposure after sunscreen use can interfere with its effectiveness in the form of a decreased SPF level. The purpose of this study is to determine and compare the persistence of organic and inorganic sun protection factor 30 (SPF 30) sunscreens after 1.5 hours of swimming.

Inclusion Criteria:

• Female or male swimming athletes aged 18-40 years.
• Practice swimming at least 3 times a week with a duration of 1.5-2 hours per practice in the morning or afternoon.
• Willing to be the subject of research by signing the consent.
• Do not have skin diseases.
• Do not have a history of allergies to sunscreens.

Exclusion Criteria:

• Existence of skin lesion in the test area.
• In the treatment of phototherapy.
• Using drugs with photosensitivity side effects.
• History of skin malignancy, history of photosensitivity reactions or history of disease affected by UV rays.
• Exposure to direct sunlight to the test area 24 hours before the study and during the study period.
• Absence of erythema response 24 hours after the radiation test.
• Erythema occurs in the entire test area box 24 hours after the radiation test.