Facepiece 4
Facepiece 4 : That portion of a respirator that covers the wearer's nose and mouth in a half-mask facepiece, or the nose, mouth, and eyes in a full facepiece. It is designed to make a gas-tight or dust-tight fit with the face and includes the headbands, exhalation valves, and connections for airpurifying device, or respirable gas source, or both