Here this study gives the health hazard data and the treatments for some of the compressed gases. Generally the standard procedure in gas based accidents is as follows:
(1) Remove the casualty from the danger area, provided this can be one without danger to you.
(2) Loosen the casualty's clothing and administer oxygen if this is available.
(3) If breathing is stopped, apply artificial respiration through a properly trained person. Do not use the mouth-to-mouth method if the gas responsible is hydrogen cyanide. A capsule of amyl nitrite should it: broken and held under the nose of a victim who has inhaled hydrogen cyanide. Again immediate medical attention must be obtained.
(4) Transport the casualty to hospital if the situation needs it. Give details of the gas responsible and of the treatment given.