[principle of nitrogen poisoning] when the concentration of nitrogen in the air is too high, that is, the oxygen content drops to below 19.5%, the partial pressure of oxygen inhaled by the human body decreases, resulting in hypoxia and asphyxia. Entering the hypoxia environment, the blood in the human artery will drop to a low level in 5-7 seconds, then syncope in 10-12 seconds, and die if there is no oxygen supply in 2-4 minutes.

[nitrogen poisoning state] inhalation of high concentration nitrogen (nitrogen content is more than 90%) will quickly lead to coma, and even death due to respiratory and cardiac arrest in severe cases. Inhalation of low concentration of nitrogen may cause chest tightness, shortness of breath, weakness, irritability, extreme excitement, running, shouting, trance, unsteady gait and coma.

[first aid on poisoning site] personnel exposed to nitrogen may be in a dangerous state before obvious signs appear, so they should leave the site immediately, transfer to fresh air, and carry out medical rescue quickly.

[summary] nitrogen is a colorless and odorless gas, which is often not easy to be found, and it is called invisible killer or silent killer. Therefore, only by understanding the characteristics of nitrogen, strengthening the study of process technology, being familiar with the dangerous and harmful factors in the workplace, strictly eliminating illegal operation, and effectively preventing, can the harm of nitrogen be completely avoided.