氧是人类生存必不可少的重要物质,人主要是通过吸入空气而得到它。当环境空气中氧缺乏时,既使无有毒物质存在,也会威胁人的健康和生命安全,轻则有头痛、头晕、呼吸困难、心跳加快、脉弱、全身无力等不适、重则出现精神恍惚,意识丧失,甚至会造成“闪电式”窒息以至死亡,这就是所谓的环境缺氧症。 Oxygen is an indispensable and important substance for human beings. People obtain it mainly by inhaling air. When the lack of oxygen in the ambient air, even without the presence of toxic substances, will also threaten the health and safety of human beings, ranging from a headache, dizziness, difficulty breathing, rapid heartbeat, pulse weakness, general weakness and other discomfort, Trance, loss of consciousness, and even cause “lightning” suffocation and even death, which is the so-called environmental hypoxia.