Hand burns surface area: A rule of thumb.

•Original research study with potential for immediate clinical use in triage, referral, research, and comparison of acute burns of the hands.•The estimation of the total body surface area of the hand (volar, dorsal, radial and ulnar surfaces) as 80 thumbprints.•The use of the thumbprint as 1/30th of 1% total body surface area (0.0333%).•A diagram of the number of thumbprints on each surface of the hand, generated from participants who were health professionals familiar with burns.