Oxygen-pressurized hyperbaric chambers have had an excellent safety record, but the pure oxygen environment does pose a risk if a fire occurrs in the chamber. In the event of a fire, the operator's initial response should be to shut off the oxygen supply to the chamber (to reduce oxygen supply to the fire) and activate the chamber's emergency decompression system, supplementing the chamber's overpressure relief valves to reduce pressure build-up in the chamber and the potential for structural failure of the chamber.

ASOS (Automated Shut-Off System) is designed for use with oxygen-pressurized monoplace hyperbaric chambers. It is an automated system connected to the chamber oxygen supply line that monitors pressure within the chamber. ASOS is operated by the chamber oxygen supply, and does not require any outside source of power.

If chamber pressure exceeds 3 atmospheres absolute, ASOS automatically shuts off the oxygen supply to the chamber. A manual activation button mounted to the ASOS enclosure allows the operator to activate the system before the trigger pressure is reached.

A panel-mounted activation button is available as an option.