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This post was last edited by zhaolijun on 2015-8-8 at 14:25. Incident report on the burns caused by a leak in the #2 feed water pump on October 8, 2002: On October 8, 2002, the #2 feed water pump stopped operating due to a leak in its outlet check valve; the pump was shut down to relieve pressure and stop the leak. The check valve was 2 meters high, and scaffolding 1.8 meters high was erected for working on it. At 11:00 a.m. on October 9, Zhao XX from Team 2 of fitters removed the cover from the check valve. At 11:30, welder Wang X began to repair the grooves for the rubber gaskets on the check valve. During this repair work, Zhao XX noticed that water was spraying out from the check valve, and he immediately ordered work to be stopped. As Wang X stepped down from the scaffolding, high-temperature water sprayed out from the check valve in both directions, causing Wang X to suffer a second-degree burn on his left lower leg; he was hospitalized for treatment. Immediate cause: 1) Inadequate energy isolation; the outlet valve of pump No. 2 was not airtight, resulting in minor leaks. The pipeline in front of the outlet valve was at a vertical height of about 4 meters, and water accumulated inside it. When the amount of leakage reached a certain level, vaporization occurred suddenly inside the pipeline, causing the water to spray out – this was the immediate cause of the accident. 2) The isolation and pressure relief of Pump No. 2 were carried out; the actual pressure relief condition within the system could not be confirmed on-site, and the project supervisor failed to implement safety measures, which were the direct causes of the accident. Indirect cause: 1) The outlet valve of the No. 2 feed water pump is not tight, and there is no vent valve between the pump’s outlet and the check valve; as a result, water accumulated in the pipe section ahead of the outlet valve cannot be drained. 2) The maintenance personnel lacked a strong safety awareness; before carrying out the maintenance, they did not jointly verify with the operators whether the isolation safety measures were in place. These are the indirect causes of this accident. Precautionary measures: 1) Install a vent valve between the outlet valve and the check valve of the No. 2 feed water pump. 2) Strictly enforce the hazardous work permit system and the EIP energy isolation and verification system; a RAP ticket can be issued only after confirming that all safety measures have been implemented. 3) Before construction, the operators and project supervisors must verify the energy isolation measures and their implementation. 4) Maintenance personnel should enhance their self-protection awareness. 5) Strengthen the identification and analysis of work hazards to prevent accidents.