Immediately rinse a burn with cool running water for 20 minutes; avoid applying toothpaste or soy sauce

Rinsing a burn with cool running water for at least 20 minutes within 3 hours of injury reduces the likelihood of needing skin grafts to roughly 60% of the rate for those who do not perform this step. Use cool water, not ice water, as ice application can worsen the damage. If clothing sticks to the wound, do not pull it off forcefully; after rinsing, cover the area with a clean cloth and head to the hospital. Never apply toothpaste, soy sauce, sesame oil, or flour to the burn. Even if you remember to rinse later, doing so within 3 hours still provides benefit.

No cost involved. It requires 20 minutes of time.

An Australian study followed 2,495 children with burns. For kids who rinsed the burn with cool running water for 20 minutes within 3 hours of injury, the relative risk of needing a skin graft was 0.6. The 95% confidence interval for this value is 0.4–0.8, meaning the likelihood of needing a graft is roughly 60% lower than for those who did not rinse. Results from 7 combined studies also confirm that 20 minutes of cool running water irrigation within 3 hours of injury significantly lowers the chance of needing skin grafts or surgical wound treatment.

Use cool water, not ice water, as ice application can worsen burn damage. If clothing sticks to the wound, do not pull it off forcefully; after rinsing, cover the area with a clean cloth and seek medical care. Avoid applying toothpaste, soy sauce, sesame oil, or flour to the burn, as these substances can interfere with doctors’ assessment of injury severity and increase infection risk. Rinsing within 3 hours of injury remains beneficial even if done later than initially intended.

Griffin BR, Frear CC, Babl F, Oakley E, Kimble RM (2020). Cool Running Water First Aid Decreases Skin Grafting Requirements in Pediatric Burns: A Cohort Study of Two Thousand Four Hundred Ninety-five Children. Annals of Emergency Medicine, 75(1), 75-85. https://doi.org/10.1016/j.annemergmed.2019.06.028；Griffin B, Cabilan CJ, Ayoub B, et al. (2022). The effect of 20 minutes of cool running water first aid within three hours of thermal burn injury on patient outcomes: A systematic review and meta-analysis. Australasian Emergency Care, 25(4), 367-376. https://doi.org/10.1016/j.auec.2022.05.004；International Federation of Red Cross and Red Crescent Societies (2025). International First Aid, Resuscitation and Education Guidelines 2025，第 289 页：「Do not use ice-cold water」「Do not apply ice, as this may aggravate the injury」. https://www.ifrc.org/sites/default/files/2026-03/IFRC%20International%20First%20Aid,%20Resuscitation%20and%20Education%20Guidelines%202025.pdf；NHS. Burns and scalds：「do not remove anything that is stuck to the affected area」「do not put any creams, oils or butter on burns or scalds」. https://www.nhs.uk/conditions/burns-and-scalds/treatment/