In the European Union, a substantial number of chemical processing plants and petroleum refineries began operations at least two decades ago including a considerable number that are more than 50 years old.

A study conducted by the UK Health and Safety Executive in 2010 estimated that over 60% of the approximately 450 major accidents reported to the EU’s eMARS database from 1996 to 2006 were related to technical integrity and, of those, 50% had ageing as a contributory factor, underlining the importance of primary containment maintenance. Corrosion alone has been attributed as a cause of at least 20% of major accidents in petroleum refineries in EU countries between 1984 and 2012. As indicated in Figure 1 (OECD, 2017), ageing is a multi-faceted phenomenon consisting of different types of risks that must be recognised and addressed.

The JRC’s Major Accident Hazards Bureau (JRC-MAHB) published two technical briefs on criteria and good practices for inspecting management of ageing and maintenance of primary containment systems to support the inspection of these topics within the context of the EU Seveso Directive (2012/18/EU) in collaboration with the EU Technical Working Group on Seveso Inspections.

Subsequently, MAHB organised a webinar in February 2022 to present these two publications to inspectors in EU Member States and partner countries to promote information exchange on related inspection practices. The webinar generated insight into currently available guidance resources, practices and perspectives in the EU Member States, and inspection experiences on hazardous sites.

There is clear evidence that ageing of hazardous sites is an important risk factor common to all industrialized countries and therefore, requires the serious attention of government authorities and in particular the relevant inspectorates.

Protection of critical infrastructure against loss of containment relies vastly on primary containment systems, the subset of safety critical elements (SCEs) that form the hardware components of preventive barriers.

Ageing – a frequently concealed degradation agent, can pose a significant risk to primary containment systems, weakening their mechanical integrity (in terms of erosion, corrosion, fatigue, or physical stressor). Regardless of the operating lifetime, both new and old plants are prone to ageing concerning technology and procedures, people and organization, or even IT systems and cybersecurity.

Figure 1. Types of ageing from JRC-MAHB analysis in Ageing of Hazardous Installations (OECD, 2017)