  The monitoring of diver health during emergency events is crucial to ensuring
the safety of personnel. A non-invasive system continuously providing a measure
of the respiration rate of individual divers is exceedingly beneficial in this
context. The paper reports on the application of short-range radar to record
the respiration rate of divers within hyperbaric lifeboat environments. Results
demonstrate that the respiratory motion can be extracted from the radar return
signal applying routine signal processing. Further, evidence is provided that
the radar-based approach yields a more accurate measure of respiration rate
than an audio signal from a headset microphone. The system promotes an
improvement in evacuation protocols under critical operational scenarios.
