Malfunctioning fire exit at the Philippsburg Nuclear Power Station

In an unexpected incident at the decommissioned Nuclear Power Plant Philippsburg, Unit 2, a fire door remained open after a closure command on August 20, 2025. The cause of this malfunction was a malfunction in the pneumatically operated opening assist device.

The affected fire door is located in a firewall outside the control area between the auxiliary building and a connecting passage. It is designed to prevent the spread of fire in case of a fire, ensuring the safety of people and the environment.

The operator of the decommissioned Philippsburg Nuclear Power Plant Unit 2 is EnBW Kernkraft GmbH. The fire door was opened during a monthly inspection despite a lockout order. The monthly inspection revealed that the door did not close properly.

The event was classified as Category N (Normal Report) and had no or very low safety significance, according to the International Nuclear and Radiological Event Scale (INES). The INES aims to provide a rapid and understandable evaluation of an event for the public.

The INES scale has seven levels: Anomaly, Incident, Serious Incident, Accident with local consequences, Accident with wider consequences, Severe Accident, and Major Accident. This particular incident falls under the Anomaly category, the lowest level on the scale.

Events that cannot be classified into the scale (1 to 7) according to the INES handbook are assigned the "Level 0" based on national assessment, regardless of their safety significance.

For any inquiries or further information, the Ministry for the Environment, Climate, and Energy Business can be contacted via the Press Office or the Citizen's Representative. Their contact details are provided on their respective websites.

It is important to note that the INES is managed by the International Atomic Energy Agency (IAEA), the Nuclear Energy Agency (NEA) of the Organisation for Economic Co-operation and Development (OECD), and nuclear power plant operators. The opening assist device was disabled until the root cause was determined to ensure the safety of the plant.