Abstract: A protective mask includes a one-piece face piece molded of a transparent astomer. A visor in the face piece provides panoramic visibility and is resilient enough to deform under applied force to permit improved use of optical devices. Identical left and right cheek fittings permit installation of a canister on either side so that the same mask can be used by right-handed and left-handed wearers. The cheek fitting not occupied by a canister is sealed with a voicemitter which transmits the wearer's voice for use with a telephone and the like. Air deflectors inside the mask adjacent the left and right cheek fittings deflect de-fogging air along the inside surface of the visor when either left or right or both cheek fittings are used for attachment of a canister. A sealing adapter permits sealing arund earpiece shafts of eyeglasses.