The size of a burn can be quickly estimated by using the "rule of nines." This method divides the body's surface area into percentages.

• The front and back of the head and neck equal 9% of the body's surface area.
• The front and back of each arm and hand equal 9% of the body's surface area.
• The chest equals 9% and the stomach equals 9% of the body's surface area.
• The upper back equals 9% and the lower back equals 9% of the body's surface area.
• The front and back of each leg and foot equal 18% of the body's surface area.
• The genital area equals 1% of the body's surface area.