Abstract: Systems and methods that deliver a continuous partial nerve conduction block are described. A waveform generator can configure one or more direct current (DC) waveforms to provide a continuous partial nerve conduction block. One or more electrodes can deliver the one or more DC waveforms to provide the partial block to the neural structure. Feedback can be provided to the waveform generator related to the partial block. The feedback includes monitoring a property associated with the partial block and altering a parameter associated with the one or more direct current waveforms in response to the property associated with the partial block.

Abstract: A respirator system includes a facepiece, a communication system and a control system in operative connection with the communication system. The control system is adapted to control voice transmittal via the communication system based at least in part upon measurement of a variable other than sound. The variable is related to speech of a user of the facepiece. The variable may, for example, be related to respiration of the user.