For frostbite, at what water temperature should rewarming be performed in the field when safe to do so?

• A. Boiling water.
• B. Hot water around 60°C.
• C. Cold tap water.
• D. Warm water around 40°C (not hot).

Answer: (D)

Frostbite rewarming in the field should be a controlled, gentle process that brings the frozen tissue back to near-normal temperature without causing burns. The best approach is to immerse the affected area in warm water around 40°C (not hot) and maintain that temperature for about 15 to 30 minutes, or until the tissue becomes pliable, sensations return, and color improves. This temperature is warm enough to reverse ice crystal formation and restore blood flow, but not so hot that it damages tissue.

Using hotter water—around 60°C or boiling—can cause burns and further tissue injury. Cold tap water will not provide enough heat to reverse frostbite effectively and can lead to longer healing times. So, the goal is a comfortable, warm bath—not hot—to safely thaw the tissue. After rewarming, protect and insulate the area, avoid rubbing, remove constrictive items, and seek medical care if needed, especially for severe frostbite or if refreezing risk remains.