Captain Conner serves with the Arizona Department of Public Safety in Phoenix.

During the early morning hours of September 10, 1993, on a remote stretch of highway west of Phoenix, Arizona, the driver of a commercial bus lost control of the vehicle. As the bus rolled onto its side, the force tossed passengers around like rag dolls and threw some from the vehicle. Responding officers from the Arizona Department of Public Safety (DPS) found passengers with various injuries strewn throughout the crash scene.

Quickly assessing the magnitude of the emergency, DPS officers set in motion the Incident Command System (ICS). In doing so, they established a central point of command from which to direct ground and air ambulances, provided a contact for the many news media representatives converging on the area, monitored the condition of the crash victims, collected witness statements, and kept track of the equipment involved in the emergency. ICS became vital to coordinating the response among the many agencies that assisted the DPS following the collision.

At one time, public safety agencies tackled emergencies on a case-by-case basis with every resource they could muster. In times of real crisis, they called on neighboring jurisdictions for help. Then, in the early 1970s, as huge brush fires ravaged Southern California, local agencies throughout the area entered into mutual-aid agreements to pool resources with neighboring jurisdictions. Thus, the genesis of the Incident Command System came from the need to manage the response of participating agencies, and the fire service became the vanguard for emergency scene management.

In the years that followed, ICS remained primarily the forte of fire services. Recently, however, law enforcement officials across the country have come to appreciate the value of a coordinated response to emergencies.

Vehicle collisions, pursuits, officer-involved shootings, natural disasters, and civil disturbances represent only a few of the incidents for which an agency can employ ICS. Whether they require the response of one agency or many, critical incidents become more manageable with ICS.

Under those circumstances involving multiple jurisdictions, ICS allows agencies to provide a singular response. As a planning tool, ICS designates in advance the specific duties of all participants. Perhaps more important, it determines who will be in charge at the scene.

The public expects and deserves cooperation between agencies on the scene of an emergency, without jurisdictional disputes. Formalized agreements-whether between in-house participants or among other agencies-set the stage for integrated communication, centralized staging of resources, and the comprehensive management of those resources once deployed.

ICS also eliminates "ten codes," which usually differ from agency to agency and can snarl interagency communication. Instead, agencies use common terms to promote understanding and improve response times. Finally, ICS provides a manageable span of control for the incident commander, who can provide overall scene management rather than become bogged down by details better delegated to subordinates.

ICS simplifies the management of critical incidents by organizing the response into modules. Anyone in the agency, from the chief to the patrol officer, can implement ICS into its full configuration. The individual who initiates the ICS response usually assumes command on the scene, at the emergency command center, or at the field command post and becomes the incident commander. Unless formally relieved, the incident commander remains in charge and provides a single point of contact.

The incident commander oversees the entire operation through sectors, or branches, which provide a manageable span of control. Sectors can be collapsed, expanded, or added as needed during a specific incident. Others may not be needed at all for an emergency limited in scope or duration.

For example, sectors often are designated logistics, operations, personnel, and intelligence. 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.

While not essential in all deployments, the emergency command center (ECC) generally works in concert with ICS. It also may be a distinct function under the ICS umbrella. Typically, the ECC is housed in one department's command center or another centrally located site, but it can be located anywhere practical; even the trunk of a patrol car can serve as the ECC. Commanders from every agency involved in the incident should staff the ECC.

The Arizona Department of Public Safety uses ICS daily under many different circumstances. Three levels of response dictate what resources to commit to each incident. Level I incidents require that one or two officers resolve minor traffic accidents, make arrests, or conduct light crowd control.

Level II incidents require the assistance of three or more officers. They usually involve several agencies and may cross jurisdictional boundaries. Examples include collisions that result in road closures or evacuations.

Level III incidents involve three or more officers from multiple shifts, require support from other bureaus, districts, or agencies, and demand a significant response to contain, control, and recover from the emergency. Bombings and riots represent two types of Level III incidents.

Situations classified as Level II or III require the use of an incident report log. By keeping accurate records, the DPS can evaluate its response and improve its performance for future critical incidents. The log also provides documentation that might be needed later in court.

The Arizona Department of Public Safety developed an ICS manual to accommodate the diversity of emergency issues encountered each year. Designed to be used by officers on the scene, the manual contains information officers need to coordinate and control critical incidents.

For example, the manual covers statutes that articulate legal precedents and remove impediments to the agency's response. To illustrate, agencies can call the Federal Aviation Administration (FAA) and request that all unnecessary aircraft be removed from the scene of a critical incident. For this reason, the ICS manual contains a copy of the applicable statute, as well as the protocol for enlisting the FAA's assistance.

An actual event emphasizes the need to address such contingencies. During a recent incident in Los Angeles, media helicopters interfered with the apprehension of armed bank robbers and drew their fire, worsening an already-hazardous situation. By incorporating lessons learned from past incidents, agencies can develop comprehensive manuals to guide them through future emergencies.

In addition to the ICS manual, a separate document, known as a standing plan, outlines the appropriate response to events or civil emergencies that the agency encounters less often or can prepare for in advance. Examples of uses for the standing plan include crowd control at large concerts, sporting events, and civil demonstrations.

The DPS' comprehensive training program begins at its training academy with a 4-hour block of instruction. Table-top exercises test students' knowledge of ICS procedures and illustrate how they might perform during an emergency.

A more reliable indicator of performance comes later, however. Both announced and surprise disaster drills test the readiness and response capabilities of DPS employees and those from other agencies. Ironically, just 3 weeks before the bus crash, Phoenix public safety employees-including police, fire, and emergency medical services personnel-staged a simulated bus collision to test their preparedness. This training greatly enhanced the agencies' response capabilities when the real crash occurred.

Civilian employees who, by virtue of their assignment within an agency, become involved with emergency response should not be overlooked for training. Dispatchers, crime scene technicians, and logistical support employees represent integral components of the total ICS response. Like their sworn counterparts, they also should participate in drills to ensure their ability to handle emergencies.

Administrators who need additional assistance with training or any other aspect of ICS can turn to other agencies for guidance. Most state police and large municipal departments use some form of ICS. Other potential sources include local fire departments, the National Fire Academy, state emergency management agencies, and the Federal Emergency Management Agency.

The Incident Command System is a simple yet highly effective method of preparing for critical incidents. It promotes a coordinated response to emergencies with appropriate resources by providing a central point of communication, command, and control. Periodic disaster training prepares emergency responders in advance. Meticulous recordkeeping keeps investigations on track and provides an easy way to evaluate agencies' response.

At any given time, public safety officials somewhere in the world are coordinating the on-scene activities of an emergency. Labor, facilities, equipment, and communication are among the myriad issues they must consider to mitigate and control such incidents. When seconds count, Incident Command Systems allow agencies to handle emergencies quickly and confidently.