No 7 operation in limited space: no operation without risk identification, no operation without ventilation inspection, no operation without labor protection articles, no operation without supervision, no operation without electrical equipment conforming to regulations, no operation without approval, and no operation without training and drills.

Limited space refers to a closed or partially closed space, with narrow entrances and exits, not designed as a fixed workplace, and poor natural ventilation, which may easily lead to the accumulation of toxic, harmful, flammable and explosive substances or insufficient oxygen content. Limited space operation refers to the operation activities of workers entering a limited space.

Generally, workplaces in limited spaces contain various gases such as hydrogen sulfide, carbon monoxide, carbon dioxide, ammonia, methane, hydrogen cyanide, etc., among which asphyxiating gases such as hydrogen sulfide and carbon monoxide are particularly prominent.

Harmfulness of confined space operation

Poisoning hazard is easy to accumulate high concentration of harmful substances in a limited space, which can exist in a limited space or accumulate gradually during operation. The harm of hypoxia, low oxygen concentration in the air will cause hypoxia. There are flammable and explosive substances in the air, and high concentration will cause explosion or combustion when it meets fire.

Other hazards, any other environmental conditions threatening life or health, such as falling, drowning, object strike, electric shock, etc. Working in these places with limited space, if the ventilation is poor and the concentration of asphyxiating gas is high, the oxygen content in the air will drop. When the oxygen content in the air drops below 16%, people will have symptoms of hypoxia.