[Research on the characteristics and countermeasures of major confined space accidents in China].

Objective: To analyze the characteristics of major confined space accidents in China, explore the underlying causes of their high incidence, and propose targeted countermeasures. Methods: In December 2023, major confined space accident cases occurring in China from 2018 to 2022 were retrieved from official platforms including the Ministry of Emergency Management, local emergency management bureaus, and safety management websites. The occurrence patterns of these accidents were examined from four dimensions: blind rescue attempts, monthly distribution, accident types, and industry distribution. The characteristics of confined space poisoning and asphyxiation accidents were mainly analyzed from two aspects: poisoning and asphyxiant substances and accident locations. Results: From 2018 to 2022, a total of 199 major confined space accidents were recorded in China, resulting in 690 fatalities. Among these deaths, 362 (52.5%) were attributed to blind rescue attempts. Seasonal trends were distinct: 98 accidents (49.2%) and 332 fatalities (48.1%) occurred from May to July, with an average of 6.5 accidents and 22.1 fatalities per month during this period. By accident type, poisoning and asphyxiation dominated, accounting for 181 incidents (91.0%) and 627 fatalities (90.9%). The manufacturing industry had the highest incidence, with 67 accidents (33.7%) and 255 fatalities (37.0%). For major poisoning and asphyxiation accidents in confined spaces, the sewage treatment system was the most frequent location, with 98 incidents (54.1%) and 341 fatalities (54.4%). The top three causal factors for poisoning and asphyxiation were hydrogen sulfide, oxygen-deficiency asphyxia, and biogas, collectively responsible for 160 accidents (88.4%) and 552 fatalities (88.0%) . Conclusion: Blind rescue is a prominent issue in the aftermath of major confined space accidents. May to July is the high-risk period, accidents are concentrated in the manufacturing industry and sewage treatment systems, and poisoning and asphyxiation (particularly hydrogen sulfide poisoning) account for the majority of incidents. To prevent such accidents, enterprises must strictly comply with confined space operation protocols, leverage accident occurrence patterns for proactive planning, and prioritize targeted supervision.