Problems at nuclear power plants caused by human error and the measures taken during initial operations at the Kyushu Electric Power Company

At the Genkai No. 1 nuclear power plant (operated by the Kyushu Electric Power Company) two problems occurred that were caused by human error due to inadequate operational experience. The first was a leak from a damaged steam generator tube. This was caused by a measuring tape that was left by mistake in the steam generator after modifications. Working procedures and control of equipment have, therefore, been reviewed and improved. The second problem was a release of radioactive gas into the atmosphere, again due to operational error. Measures have been taken to prevent a recurrence of such an incident, the problem being caused by poor operational control over system isolation and restoration after maintenance work. (author). 2 figs