Before assessing and treating a casualty's burn, what should be done first?

Stopping the source of the burn is the first and most critical step before moving on to assessment and treatment. This is essential for ensuring the safety of both the casualty and the responder. If the source of the burn, such as flame, heat, electricity, or chemicals, is not eliminated, the burn could worsen, potentially leading to more severe injuries.

For example, in the case of a chemical burn, allowing the chemical to remain on the skin can continue to cause damage even after the initial exposure. In addition to preventing further injury, stopping the source is vital for stabilizing the situation before any medical intervention takes place. Once the source is secured, proper assessment and treatment, including pain relief and cooling the burn, can be effectively addressed.