A General System For Physiological Diver Monitoring

A general system for monitoring physiological data from a working diver at depths down to 500 metres has been developed by BENTECH A/S in cooperation with BENNEX A/S. Chosen parameters are measured by a compact "intelligent" acquisition unit and transmitted to the surface via a single twisted pair cable. Error detection and correction techniques have been employed to protect the data on the way to the surface. The surface unit displays the parameters from one or more divers on a TV screen and checks that their values lie within the limits the operator has set. Audible and visual alarms are provided together with a logging printer. A full data logging output to a cartridge recorder is also available. Parameters that have been monitored include breathing-gas temperature, breathing frequency, hot-water temperature, deep-core body temperature, and depth. Other parameters such as ECG or pulse rate could also be included without difficulty. The system has been tested out in wet-chamber simulated dives down to 350 metres and the results so far are encouraging.