When a palm is used as a measuring scale in estimating the burnt area, it is equal to

Rule of palms: The surface area of a patient's palm (including fingers) is roughly 1% of TBSA. Palmar surface can be used to estimate small burns (< 15% TBSA) or very large burns (> 85%, when unburnt skin is counted). Ref - Srb's manual of surgery 5th edition , burns