Abstract: A breathing apparatus configured to be worn on the face of a person is disclosed. The apparatus comprises a breathing manifold having an internal space with openings for a connection to the nasal passage and mouth of the user and openings for one or more gas-exchange ports. An armature holds the manifold in position relative to the face and provides pressure against the nose and mouth to provide a sealed interface between the internal volume of the apparatus and each of the nose and mouth. According to a salient aspect, the armature is configured to securely hold the breathing apparatus to the person's face without requiring additional securements such as head straps. The armature also includes one or more attachment points for supporting other components of the breathing apparatus including, for example, an air-inlet filter and an exhaust valve, through which air can be exchanged.