Estimating the Size of a Burn

Estimating the Size of a Burn

British Columbia Specific Information

Burns can be serious injuries. If you have a serious burn injury, call 9-1-1 right away. For more information, or if you are not sure if you should contact a health care provider, call 8-1-1.

According to the World Health Organization, a burn is considered serious if it:

  • covers more than 15% of the body surface of an adult;
  • covers more than 10% of the body surface of a child;
  • involves someone who is very young, elderly, in poor health, or who has a pre-existing medical condition such as diabetes;
  • is a third degree burn;
  • occurs on your face, hands, feet or genitals;
  • encircles your leg or arm; or
  • is associated with trauma.

 

Smoke inhalation is also a serious injury and requires medical attention right away. For more information, see the World Health Organization handout on the Management of Burns.

Topic Overview

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

Estimating burn size in adults

See a picture of the "rule of nines" for adults.

  • 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 groin area equals 1% of the body's surface area.

Estimating burn size in babies and young children

See a picture of the "rule of nines" for babies and young children.

  • The front and back of the head and neck are 21% of the body's surface area.
  • The front and back of each arm and hand are 10% of the body's surface area.
  • The chest and stomach are 13% of the body's surface area.
  • The back is 13% of the body's surface area.
  • The buttocks are 5% of the body's surface area.
  • The front and back of each leg and foot are 13.5% of the body's surface area.
  • The groin area is 1% of the body's surface area.

The "rule of palm" is another way to estimate the size of a burn. The palm of the person who is burned (not fingers or wrist area) is about 1% of the body. Use the person's palm to measure the body surface area burned.

It can be hard to estimate the size of a burn. If you think a burn is a certain size but you are unsure, it is best to discuss the size of the burn with your doctor.

Credits

Current as of:
July 1, 2021

Author: Healthwise Staff
Medical Review:
William H. Blahd Jr. MD, FACEP - Emergency Medicine
Adam Husney MD - Family Medicine
Kathleen Romito MD - Family Medicine
Martin J. Gabica MD - Family Medicine