Vermen event in the Philippsburg nuclear power plant (Block I)

in the nuclear power plant Philippsburg (Block I) was found during a recurring inspection that a fire protection door did not close properly. There was no danger to people and the environment.

On April 14, 2022, recurring exams on door festival systems were carried out in block one of the Philippsburg nuclear power plant. It was found that one of the fire protection doors did not completely closed when the door detection was triggered. The upper door closer was readjusted accordingly. Then the door closed properly when the test was repeated.

The affected fire door is in the machine house of the nuclear power plant, which is currently being dismantled. It separates a room in which combustible material is stored from the rest of the machine house.

In the event of a fire, the door is constructed so that it automatically closes to prevent fire and smoke from spreading between adjacent areas of the room until the fire can be extinguished. In the present case, this function was no longer sufficiently guaranteed.

The safety meaning of the findings is low

Since all other fire protection facilities and measures such as fire detection by smoke detectors and fire fighting were available without restrictions, the security of the finding is low. There were no effects on people and the environment.

The classification holder was as follows: registration category n (normal message); International Nuclear and Radiological Event Scale (Ines) zero (no or very low security meaning).

The events that are important for nuclear security must be reported to the nuclear supervisory authorities of the federal states according to the nationwide criteria of the nuclear security and registration regulation- ATSMV. The aim of the reporting procedure is to monitor the security state of nuclear power plants, to prevent the occurrence of similar errors in other nuclear power plants and to incorporate the knowledge gained into safety improvements.

different categories for reportable events

The reportable events are assigned to different categories:

• category S (immediate registration)
  Events that the supervisory authority must be reported immediately so that they can initiate checks or initiate measures as soon as possible. This also includes incidents that indicate acute safety -related defects.
• category E (message within 24 hours)
  Events that the supervisory authority must be reported within 24 hours so that they can initiate controls promptly or initiate measures. This also includes events whose cause, for security reasons, has to be clarified at short notice and, if necessary, remedied within a reasonable period. As a rule, these are events that are potentially - but not directly - in terms of safety.
• category N (message up to the fifth working day)
  Events that the supervisory authority must be reported within five working days in order to be able to identify any security weaknesses at an early stage. As a rule, it is events of subordinate safety importance that go beyond usual operational individual events if the system is properly condition and operation. Non -availability of components or systems, which are deliberately caused by procedures specified in the operating manual, do not have to be reported if this is also taken into account in the safety specification of the operating manual.
• International rating scale Ines : Due to an agreement between the operators of the nuclear power plants and the Federal Minister for the Environment, Nature Conservation and Nuclear Safety, reporting events in nuclear power plants are also classified according to the evaluation scale Ines of the International Atomic Service Agency (IAEA) and the Nuclear Energy Agency (NEA) of the Organization for Economic Cooperation and development (OECD) evaluated. The aim is to assess an event quickly and understandably for the public.

  The scale has seven stages:
  1 - disorder
  2 - incident
  3 - Serious incident
  4 - local impact accident
  5 - accident with more far -reaching consequences
  6 - serious accident
  7 - catastrophic accident

reportable events that are not to be assigned to the scale (one to seven) according to the Ines manual are assigned to the national evaluation of the "level zero".