Abstract: Altitude simulation breathing systems create at near sea level, oxygen partial pressure equivalents to a desired “simulated” above ground level altitude by gas mixing and induce low oxygen content (hypoxia) in a subject through the identical physiologic mechanisms as high altitude. At the heart of all prior art is the oxygen sensor; all decisions about gas mixing are based on a direct measurement of oxygen concentration. These sensors respond slowly requiring them to be used with a reservoir; a volume of gas maintained at a given oxygen concentration. The current invention uses flow based technology and eliminates reservoir associated shortcomings. Central to the function of the current invention is the ratiometric addition in real time of nitrogen to inspired room air which is unpressurized, uncontrolled, and inspired normally. In short, we present new technology to this field not based on oxygen concentration that offers significant improvements in safety, reduced mechanical complexity, and size.

Abstract: A hypoxia awareness training system provides education on high altitude flight physiology and simulates atmospheric oxygen concentrations found normally at sea level and at high altitudes. It can be programmed to reduce oxygen levels to correspond with specific altitudes. The rate of change in simulated altitude (oxygen reduction) can be programmed to correspond with normal ascent rates of specific aircraft, thus providing a platform for training pilots to recognize symptoms of themselves or their crewmates under hypoxic conditions. This training is not limited by geographic location and can be performed in a safe and controlled environment, where poor judgment and coordination will not result in disaster.