Add to ORKG"A sizing program for oral-nasal oxygen masks, based on total face length and lip length, has been developed through a reanalysis of the 1950 USAF Anthropometric Survey head and face data. Face forms, based on this sizing program, have been constructed for use in the preparation of such masks. The MC-1 Oxygen Mask, an oral-nasal, pressure-demand type mask, has been fabricated in accordance with this sizing system and through the use of these face forms. In the fit-tests, one-hundred-forty-nine of one-hundred-fifty subjects fit-tested were satisfactorily fitted in their indicated sizes. This report includes a discussion of the theoretical and practical aspects of the sizing procedure. Design limits and related statistical material and sugges...