A disposable comfort sheet has a waterproof layer and an absorbent layer, with adhesive strips applied to the waterproof layer along side edges. The sheet is adapted for use with a patient transfer device having upper and lower counter-rotating belts, and protects the upper belt against contamination. The patient transfer device may have registration marks for installation of the sheet, and indicator marks can be printed at predetermined locations on the waterproof layer for alignment with the registration marks. The sheet may include various means for indicating prior use by a patient, such as an ink pattern made of a heat-sensitive or moisture-sensitive ink. The sheet may further include a peel-away layer releasably bonded to the absorbent layer, with additional longitudinal adhesive strips applied to the side edges of the peel-away layer. The peel-away layer protects the lower belt against contamination from the sheet after a patient is delivered.