Method and apparatus for monitoring oxygen partial pressure in air masks
Researchers at NASA’s Johnson Space Center have developed an innovative oxygen warning system capable of detecting and preventing oxygen deprivation, or hypoxia, in the user. If oxygen partial pressure dips below a safe, predefined level, the sensor’s alarm and aggressive vibration are capable of arousing an individual who may have become impaired by symptoms of hypoxia such as drowsiness, slowed reaction times, and blackouts. The partial pressure warning system can be incorporated into virtually any commercially available oxygen mask.
NASA’s oxygen sensor was originally developed to reduce the incidence of hypoxia in aircraft pilots. The innovation has several applications beyond aerospace, including oxygen systems for the military, firefighting, scuba diving, mountain climbing, as well as medical oxygen systems.How it Works
The oxygen partial pressure sensor and vibrating alarm is composed of an electrochemical oxygen sensor, a voltage comparator, and a vibrator motor. All of these components are installed directly within the breathing mask. When the partial pressure of oxygen in the system falls below a predefined set point, as measured by the electrochemical oxygen sensor, the voltage comparator triggers the vibrator motor to deliver vibration within the mask. In the event of an oxygen system malfunction, this sensor’s vibration provides immediate warning that hypoxia conditions exist. The sensor’s vigorous tactile and aural stimulation allows the user to take corrective action before succumbing to the dangerous, and potentially fatal, effects of hypoxia.Why it is Better
Currently available oxygen sensors are limited in three important ways:
This sensor measures the product of oxygen concentration and total ambient pressure (oxygen partial pressure). Thus the sensor will trigger the alarm circuitry for low oxygen concentration at constant total pressure, constant oxygen concentration at low total pressure, and any combination of low oxygen concentration and low total pressure that drops the product below a user-defined set point. The high-pitched alarm provides a warning system that alerts the user, along with others in the vicinity, of life-threatening hypoxia conditions, and the “nose beater” vibration is vigorous enough to stimulate the user to take corrective action.Patents
Johnson Space Center has received patent protection (U.S. 7,040,319→) for this technology.
This technology is being made available through JSC’s Technology Transfer and Commercialization Office, which seeks to transfer technology into and out of NASA to benefit the space program and U.S. industry. NASA invites companies to consider licensing this Method and Apparatus for Monitoring Oxygen Partial Pressure in Air Masks (MSC-23309-1) for commercial applications.