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Hazardous Incident Ordinance (Seveso III Directive)

Operators and investors

Adequate safety distance, safety reports, accident prevention concepts

Accidents involving hazardous substances can have a variety of effects. In addition to causing costly interruption of ongoing operations, they can result in considerable damage to property, people and the environment. One of the numerous regulations for the safe handling of hazardous substances is the Seveso III Directive (2012/18/EU), essentially implemented in German national law by the amended Major Accidents Ordinance. Here you can view the current version of the 12th BImSchV.

The Major Accidents Ordinance defines its scope and the extent of the resulting obligations for plant operators regarding thresholds for certain hazardous substances. Also decisive for this are the requirements of hazardous substances law and the CLP Regulation.

We support and advise you on the implementation of the operator’s obligations.


  • Examination of the applicability of the Major Accident Ordinance
  • Creation of concepts for preventing accidents
  • Preparation of safety reports
  • Preparation of alarm and hazard prevention plans
  • Preparation of the operational and environmental hazard source analysis, e.g. according to the HAZOP method
  • Consideration of possible interventions by unauthorised persons
  • Establishment and review of safety management systems
  • Advice on measures to prevent accidents or limit their effects
  • Calculation of the appropriate safety distance
  • Implementation of Sec. 50 BImSchG – Calculation of appropriate distances according to the requirements of the KAS-18 guidance according to the respective area of application
  • Preparation of expert reports acc. to Sect. 29a and Sec. 29b BImSchG
  • Performance of accident impact assessments (fire, explosion, spread of pollutants, etc.) with different programs (EFFECTS, ProNuSs, VDI models etc.)
  • Creation of information brochures in accordance with Sec. 11 Major Accidents Ordinance (public information)
  • Appointment of external accident officers
  • Conducting seminars and in-house training
Years of experience
Safety reports prepared
KAS-18 reports

Frequently asked questions

Whether the Major Accidents Ordinance is applicable to an enterprise depends on the quantities of certain hazardous substances that are or may be present in the enterprise. It is immaterial whether the substances are stored in the strict sense or not (e.g. handling facilities). Which hazardous substances are regulated by the Hazardous Incident Ordinance can be found in its annex. Some hazardous substances are mentioned by name, e.g. petrol or hydrogen. Other substances are subject to the Major Accidents Ordinance because they have certain hazard characteristics, such as acute toxicity (e.g. potassium cyanide) or environmental hazards (e.g. zinc oxide). Substances that are not listed by name or by their hazard characteristics are not covered by the Major Accidents Ordinance. This also applies if they are otherwise hazardous, e.g. from an occupational safety point of view. An example would be concentrated sulphuric acid. In addition to the above-mentioned properties, the accident-relevant substances must be present above certain quantity thresholds for the establishment to be subject to the Major Accidents Ordinance. However, if several different accident-relevant substances are present, they must be added together (see addition rule).

In the case of an establishment in which no individual hazardous substance is present in a quantity equal to or greater than the respective quantity threshold, the addition rule shall be applied to determine whether the establishment is an operating area within the meaning of the Major Accidents Ordinance. In this process, quotients are formed from the individual quantities of hazardous substances and the respective quantity thresholds for the hazard characteristics from the list of substances in Annex I of the Hazardous Incident Ordinance. The quotients are then added up according to certain rules. This is done with both the quantity thresholds for the upper and the lower class. Depending on which quotient sum is greater or less than 1, the establishment is not an operating area within the meaning of the Major Accidents Ordinance, one of the lower or one of the upper class.

The terms “upper tier” and “lower tier” were introduced with the Seveso III Directive 2012/18/EU, whose national implementation in Germany is the Major Accidents Ordinance of 2017. They are nothing more than additionally introduced terms for operating areas for which the basic obligations or additionally the extended obligations (these terms continue to apply) must be fulfilled.

Yes. According to Annex I of the Hazardous Incident Ordinance, it also applies to waste if it has hazardous substance properties that are relevant to an incident. This applies despite the fact that the CLP Regulation does not actually apply to waste. Instead, according to the List of Wastes Ordinance (AVV) in conjunction with the Waste Framework Directive (Directive 2008/98/EC), hazard-relevant properties HP 1 to HP 15 are assigned. This is done in a simplified form via the hazard characteristics (CLP Regulation) of the ingredients. However, this approach is not compatible with the requirements of the CLP Regulation for the classification of (waste) mixtures, in particular, it is not possible to infer the correct classification according to the CLP Regulation from a hazard characteristic HP… once it has been assigned. In order to avoid having to go through the actual procedure for classifying the waste as a mixture according to the CLP Regulation, the Commission for Plant Safety developed the KAS-25 Guidance Document in 2012. This assigned a hazardous substance property to a waste described by the six-digit AVV No. in accordance with the then valid Substances Directive 67/548/EEC, on which the then version of the Major Accidents Ordinance was also based. The assignment was based on conservative estimates. However, this guideline is no longer applicable, as in 2017 the Major Accidents Ordinance was converted to the hazardous substance properties of the CLP Regulation. For the transitional period until the KAS-25 is updated, a guideline published by the North Rhine-Westphalia State Office for Nature, Environment and Consumer Protection (LANUV NRW) is available for the allocation of waste to the Major Accidents Ordinance.

No. Despite the very similar designations, we are dealing with two different terms. Substances are hazardous to water in the sense of the Major Accidents Ordinance if their toxicity to certain aquatic organisms exceeds specified values according to the CLP Regulation (Regulation (EC) No. 1272/2008). The definition of substances hazardous to water with a water hazard class originates from the Federal Water Act (WHG) and is much broader than that of the Major Accidents Ordinance / CLP Ordinance: For example, rapeseed oil methyl ester (raw material for biodiesel) is not hazardous to water because it falls below the aforementioned toxicity values. However, it is hazardous to water (lowest water hazard class WGK 1) because it floats on the water surface. By floating on the water surface, it can harm aquatic organisms, insects and birds, for example by preventing their oxygen uptake or mobility. In summary, any substance hazardous to waters within the meaning of the CLP Regulation or the Major Accidents Ordinance is hazardous to waters within the meaning of the WHG, but not vice versa. Click here for more information on water pollution control (AwSV).

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Dagmar Renn

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Frank Sutter

Weyer und Partner (Schweiz)
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As-U Gamerith Weyer
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Dr. Klaus Wörsdörfer

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