The European Union's SEVESO Directive provides regulation guide for the protection against major hazardous accident occurrence involving the use of dangerous substances, controlled by the 219/2011. (X.20.) Government Decree in Hungary. Above regulation determines the classification of plants concerned (top and bottom-tier hazardous plants, under-threshold plants) on the basis of the present dangerous substances at the site. Operators covered by the requirements should provide certification of compliance according to risk levels and the safety documentation should be submitted to the Authority (Safety Analysis / Report and SAPP).

Licensing the operation of a hazardous plant is legally bound by the existing legislation to the fulfillment of quantitative criteria. To prove the compliance, a quantitative risk assessment should be established, summarizing and identifying the operator's activities, the operating technology and procedures. The operator should identify all risks arising from its activity (the individual and social risk of mortality). The supposed major accidents should be identified and risks originated from those should be determined and summarized. Quantitative specifications should be determined and documented for the authority, as proof of compliance with the statutory criteria.