Explosion in the Turbine Hall of a Nuclear Power Plant
A hydrogen leak occurred on the a coolant pipe of an electrical generator located in the turbine building, at 200 m from the reactor. Because of the welding works ongoing at that moment on the pipe, the hydrogen ignited and an explosion and a fire followed the leak, with one fatality and a severe injury. The fire brigade of the plant were able to extinguish the fire. There has bot been any radioactive release, because the accident occurred in the non-nuclear area of the plant. According to the source (ARIA) the investigation attributed to a human error the cause of the incident.
Event Date
May 21, 1993
Record Quality Indicator
Region / Country
Event Initiating System
Classification of the Physical Effects
Nature of the Consequences
Causes
Cause Comments
Soldering work was ongoing on the pipe when the incident occurred. Authorities pointed out a human error. However, with the scare information available, the cause could be equally well be attributed to wrong (maintenance) procedures.
Facility Information
Application Type
Application
Specific Application Supply Chain Stage
Components Involved
cooling system, turbine-compressor unit, turbine building
Storage/Process Medium
Location Type
Location description
Industrial Area
Operational Condition
Pre-event Summary
The nuclear reactor was stopped and under maintenance. Soldering work was ongoing on the affected pipe.
Lessons Learned
Lessons Learned
The ARIA report does not mention any lesson learned, only the probable classification of the accident to a human error. The event description does not provide enough details to draw specific conclusion. Nevertheless, soldering/welding a hydrogen-containing component requires always the preliminary evacuation of the hydrogen, what does not seems that has happened in this case. In alternative to a human error, this event could also hint at lack of adequate procedures, their or inadequate communication.
Event Nature
Emergency Action
Plant staff extinguished the fire rapidly
Release Type
Release Substance
Hydrogen Release Concentration (%)
100.00
Ignition Source
Detonation
No
Deflagration
No
High Pressure Explosion
No
High Voltage Explosion
No
Flame Type
Source Category
References
References
Event description in the French database ARIA
https://www.aria.developpement-durable.gouv.fr/accident/4501/
(accessed December 2020)