2.3 Availability and Access to Records The safety case is expected to make reference to detailed calculations, assessments, procedures, or similar. All information referenced within a safety case must be retained by the petroleum undertaking and must be made available to the CER if required. Without prejudice to this, where there is a specific requirement fora particular type of record to be retained by the petroleum undertaking, this is identified in these Guidelines. 2.4 Safety Case Structure The structure and outline contents for each of type of safety case is set out in sections 4 to 8 of these Guidelines. The structure set out in each of those sections is suggested as an appropriate structure for each respective type of safety case. A petroleum undertaking is not bound to follow this structure, but must supply all of the information identified. 17 Section M of the Act. 18 Section M) of the Act.