gas mixture, affected by the seawater intrusion, spread and accumulated quickly in this space.

It should be noted more than eight h passed after the leaks were discovered, but repair of the broken pipelines was not completed because of poor emergency disposal. According to estimation, the total amount of oil leakage from the ground, closed conduit, and sea was up to 2000 tons during this period. However, people on site were not aware of the risk and still used non-explosion-proof tools to open the cover plate of the closed conduit without taking protective measures. The oil and gas mixture ignited and detonated from the exposed sparks of the mechanical drilling.

The explosion seriously destroyed the block and caused extensive marine pollution. The damaged pipelines located in the dangerous section weresystem. Collectively, managers and leaders should provide the organizational systems and drive the organizational culture that determines not only what people in the organization do, but more importantly, how they do it.

In addition, there were several external factors related to the occurrence of the oil leaks. The local supervision department of work safety who is the lead unit for the protection of underground pipelines failed to perform its supervision duties well because the coating overhaul for the Donghuang oil pipelines was not finished within two years. Moreover, it failed to urge the pipeline enterprise to carry out the hazard identification and regular maintenance for oil pipelines and did not realize the closed-loop management of the safety inspection through the form of "reviewing". There was also some irrationality in