The competent authority is required, with respect to the operators of operational areas as defined in the Major AccidentsRegulation to determine which operational areas or groups of operational areas, based on their geographic location, their distance from one another, and the hazardous substances present in their facilities, may have an increased likelihood of major accidents or where such accidents may have more severe consequences (domino effect). For this assessment, the authority shall use, in particular,

• the information provided by the operator in the notification and in the safety report,
• the information submitted by the operator in response to a request from the competent authority for additional information, and
• the information obtained by the competent authority through monitoring measures.

The information to be reported by the operator also includes conditions in the immediate vicinity of the facility that could trigger a major accident or exacerbate its consequences, e.g., details regarding neighboring operational areas, other facilities not covered by the Major Accidents Ordinance, and areas and developments from which a major accident could originate, or which could increase the likelihood of a major accident occurring, or which could exacerbate the effects of a major accident and domino effects. If the authority has additional information beyond this, it must make it available to the operator without delay, provided that this is necessary for cooperation with the operator.