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At around 13:49 on May 3, 2018, a flash explosion occurred inside Reactor No. 1 in the hydrogenation unit of a certain pharmaceutical and chemical company during the catalyst removal operation, resulting in 1 death and direct economic losses of 1.446 million yuan. I. Course of the accident: On May 2, 2018, the company suspended all operations across its plant for maintenance work. The reaction in Hydrogenation Reactor No. 1 of Phase 1 of hydrogenation was completed at 00:53 on May 3. After standing and material compression operations, two ethanol washing processes were carried out. At 5:44, tap water (about 200 liters) was added and stirring was started, until the accident occurred. On the afternoon of May 3, Wang, the deputy director of the hydrogenation workshop, arranged for the removal of the catalyst from Hydrogenation Reactor No. 1. At around 13:41, the manhole of Hydrogenation Vessel No. 1 was opened. Subsequently, Wang opened the vacuum valve on that reactor three times in succession, allowing a large amount of air to enter Reactor No. 1, where it combined with the ethanol vapor inside to form an explosive mixture. Then, Mr. Wang went to the manhole of that reactor and used water to wash away the residual catalyst from the stirrer blades and the reactor walls of Reactor No. 1. During the flushing process, Reactor No. 1 for hydrogenation experienced a flash explosion, and Wang was thrown away by the shock wave from the explosion. II. Direct and indirect causes of the accident (1) Direct cause of the accident: Wang violated safety procedures by operating the equipment with the manhole of Hydrogenation Reactor No. 1 open, without applying nitrogen protection; instead, he started the vacuum pump, which allowed a large amount of air to enter the reactor. This air mixed with ethanol vapor to form an explosive mixture. At the same time, the catalyst, Raney nickel, caught fire upon contact with air, resulting in a flash explosion – this was the direct cause of the accident. (II) Indirect causes of the accident 1 ● Inadequate operating procedures: The company did not establish separate safety operating procedures for the task of removing the catalyst (Raney nickel); only general guidelines were provided in the operation instructions, stating that nitrogen should be introduced into the reactor after the manhole was opened. The regulations regarding preventive measures against risks such as spontaneous combustion of Raney nickel when exposed to air during catalyst removal are not strict or clear enough. 2 ● The work approval process is a mere formality: the enterprise’s maintenance workshops do not exercise proper oversight in approving maintenance tasks, fail to verify on-site whether measures to isolate air have been implemented, and issue maintenance work orders arbitrarily ； Mechanic identify operational safety risks on-site and formulate risk control measures, while the company’s safety supervision measures are inadequate. 3 ● Inadequate performance by relevant personnel: The company’s key executives, production managers, and other supervisors failed to fulfill their responsibilities regarding safety management. There was inadequate effort in identifying and addressing safety hazards, as well as in providing safety training to employees. Employees who engaged in illegal working practices were not stopped or corrected in a timely manner, which created potential risks for accidents. III. Determination of accident liability and recommendations regarding the handling of those responsible for the accident and the entities involved (I) Persons responsible for the accident and recommendations for handling them 1. Wang Moumou, the deputy director of the hydrogenation workshop, violated safety procedures during the operation of removing catalysts from the hydrogenation reactors, which led to the accident; given that he died in the accident, it is recommended that no further action be taken against him. 2. Qian, the director of the maintenance workshop, issued maintenance work orders without verifying on-site whether the measures to isolate air had been implemented; he is responsible for the occurrence of the accident. It is recommended that the company take action against him in accordance with its relevant rules and regulations. 3. Su Moumou, the company’s deputy general manager, is responsible for the daily production management of the company. The failure to conduct a risk analysis of production operations and to establish corresponding operating procedures is responsible for the occurrence of the accident; it is recommended that the company handle this matter in accordance with its relevant rules and regulations. 4. Ren Moumou, the general manager of the company, as the person in charge of the enterprise, failed to organize relevant personnel to establish sound safety operating procedures, nor did he ensure effective implementation of safety training programs within the company; he is therefore responsible for the occurrence of the accident. It is recommended that the local authorities responsible for work safety impose a fine of 30% of his annual income for 2017, in accordance with Article 92, Item (1) of the Work Safety Law of the People’s Republic of China. (II) Unit responsible for the accident and recommendations for handling: The company failed to provide adequate safety training to its employees, failed to ensure that they followed the proper procedures for removing catalysts, and did not conduct a proper risk assessment of the hazards associated with such operations; it is therefore responsible for the accident. It is recommended that the local authorities in charge of work safety impose a fine of 350,000 yuan on this company, in accordance with Article 109(1) of the Work Safety Law of the People’s Republic of China.