ICS deployment during a large-scale vehicle crash would not require the services of the intelligence sector. However, other sectors, such as traffic control, hazardous materials cleanup, or media liaison, may become necessary. Personnel officers would assist at the scene or follow up at the hospital. Operations staff would coordinate equipment needs, such as ambulances, tow trucks, and fire department resources. Sector leaders keep the incident commander apprised of their sectors' actions and needs, allowing the incident commander more easily to match resources to existing conditions or anticipate future demands.
Checklists ensure that sector leaders complete essential tasks during the emergency.
Given the demands placed on personnel at the scene, sector leaders easily could overlook a possible resource or legal or departmental requirement. Sectors, or component parts within sectors, usually vary from department to department. More important than the number and type of sectors is the capability of the agency to respond to various emergencies under a dedicated set of plans that may include allied agencies. It also may be a distinct function under the ICS umbrella. The Arizona Department of Public Safety uses ICS daily under many different circumstances.