Objective Research shows that previous experience of major incidents has positive impacts on awareness and preparedness of organisations. This manuscript aims to examine the preparedness indicators of health organisations against major incidents in two different types of organisation: those with direct involvement in response to the Bam earthquake and other organisations.

Method A descriptive study was conducted, and 230 questionnaires were distributed among the health managers in both types of organisations to compare the questionnaire results between them.

Result A total of 114 questionnaires were returned. 85% of the respondents were male, and 15% were female. Considering the organisational factor, a significant difference between the organisations was observed. Considering the communication factor, only differences in relationship with outside stakeholders and knowing the responsibility of other organisations were significant. Rehearsal and multiagency plans for warning were considerably different in the organisations. In planning, coordination, training, business continuity and cultural factors, there were no important differences. For resource variables, only the statement of sufficient resources and tools for the employees was significantly different, and, for the policy factor, there were significant differences in two variables: incorporation of major incident issues into the service design and management of voluntary efforts in a major incident.

Conclusion The findings have implications for health organisations in developing countries, especially in the Middle East. A major incident-management system re-engineering is required to bring the lessons learnt from previous major incidents into preparedness efforts and to shift individual-based activities toward systematic approaches in major incident management.