Physiological effects of oxygen

Asphyxiation and Toxicity Hazards An asphyxiant is a chemical (either a gas or a vapor) that can cause death or unconsciousness by suffocation (BP, Hazards of Nitrogen and Catalyst Handling, 2003). A simple asphyxiant is a chemical, such as N2, He, or Ar, whose effects are caused by the displacement of 02 in air, reducing the 02 concentration below its normal value of approximately 21 vol %. The physiological effects of oxygen concentration reduction by simple asphyxiants are illustrated in Table 23-18 (BP, Hazards of Nitrogen and Catalyst Handling, 2003). 

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