Seveso (the Seveso Directive) is the European Union’s major-accident-hazards law, named after the 1976 dioxin release at a chemical plant in Seveso, Italy. It requires operators of establishments holding dangerous substances above threshold quantities to prevent major accidents and limit their consequences for people and the environment. It is a regulatory regime, not part of IEC 61511, and it is the parent framework that EU member states transpose into their own national law. The current version is Seveso III, Directive 2012/18/EU.
Like the UK’s COMAH, which is the best-known national implementation, Seveso is risk-based and tiered: lower-tier and upper-tier operators carry escalating duties, and upper-tier sites must prepare a safety report demonstrating that the major-accident hazards are controlled. Functional safety is a means here, not an end. A safety instrumented system (SIS) designed and verified to IEC 61511 is one of the protection layers an operator relies on to show that a major-accident risk has been brought to an acceptable level.
Key Points
- Seveso is the EU’s major-accident-hazards directive, named after the 1976 Seveso, Italy disaster, now in its third version (Seveso III, Directive 2012/18/EU).
- It applies to establishments holding dangerous substances above threshold quantities, with tiered duties and a safety report required for upper-tier sites.
- Member states transpose it into national law; the UK’s COMAH Regulations are the most familiar implementation.
Example
An upper-tier Seveso establishment in Germany running a large ammonia refrigeration plant must notify the competent authority and prepare a safety report. The IEC 61511-rated safety instrumented functions on the ammonia system are documented there as protection layers that limit the likelihood of a major release.
See Also: COMAH, ALARP, major accident, PSM
Cited Sources
- Directive 2012/18/EU (Seveso III) on the control of major-accident hazards, EUR-Lex
- European Commission, Industrial accidents (Seveso)