Researchers at the Defense Advanced Research Projects Agency (DARPA), an agency of the United States Department of Defense responsible for the development of new military technologies, are now tasked with developing scuba gear and microsystems to help enable navy divers to perform in extreme conditions, and aid against decompression sickness or sudden death due to reaching the surface too quickly.
Navy divers are currently being trained in breathing static gas mixtures at prescribed pressures and durations. Among Darpa’s list of proposed innovations are inserting small amounts of nitric oxide into the diver’s lungs to help reduce the bubbles that cause decompression sickness, as well as incorporating biometric devices in the gear of navy divers, such as hip-scale gas chromatograph / mass spectrometer (to actively and rapidly monitor inspired and expired gases/agents); capacitive micro-machined ultrasonic transducer arrays (for in vivo bubble detection and environmental monitoring); and gas/vapor control elements such as MEMS gas pumps, valves and nebulizers that could be integrated into a physiologic control system for extreme environments.
The new system is slated to perform in an extreme combat profile, which consists of a military freefall and brief parachute deployment from 35,000 feet, then a combat dive down to 200 feet at seawater for at least two hours. After reaching the surface, the diver must go down twice with increasing depths at shorter intervals, and also withstand extraction in an unpressurized aircraft below 14,000 feet mean sea level.