Office of Operations
21st Century Operations Using 21st Century Technologies

TRAFFIC CONTROL CONCEPTS FOR INCIDENT CLEARANCE

1.0 INTRODUCTION

The surface transportation system is crucial to our quality of life and economic wellbeing by moving people, goods and services in a safe, efficient, and orderly manner. Unfortunately, the development of the road system has not kept up with growing demands and this has resulted in congestion, delays, and negative environmental impacts. These adverse conditions are magnified when incidents occur that further the degradation of traffic flow and increase the safety risk for the traveling public as well as the incident responders. While much has and is being done to address and improve safety, over 6.4 million vehicle crashes occur annually. 1 The severity of the reported incidents range from inconvenience and minimal property damage to multi-vehicle, multi-fatality, major structural damage and threatening hazardous cargo materials spills. While each crash is unique and has a varied impact on the travel and safety of others, they must all be safely cleared; and they must be cleared as quickly as possible to minimize the exposure of potential harm for the victims, the first responders, and the motorists traveling through the crash location.

Traffic incident management (TIM) deals with reducing congestion and improving safety for all concerned. The focus of incident management is to develop procedures, implement policies, and deploy technologies, not only to identify incidents more quickly, but to improve response times and manage the incident scene more effectively and efficiently. Traffic control is the element of scene management that helps to secure the scene, protects other motorists, and allows first responders the opportunity to safely deploy the necessary actions. Normally, law enforcement, fire-rescue, and / or transportation service patrols are those first on the scene and charged with the responsibility to implement immediate traffic control. As with any emergency situation, these professionals must use whatever is available to them at the moment, highlighting the importance that they carry the right tools and have the necessary training to safely implement the traffic control under time-limiting conditions. It is also equally important to adapt the traffic control needs as conditions change if a longer time period is required before the situation can return to normal. Under the incident command system (ICS), traffic control allows responders to safely meet the present needs, but also be sensitive to the delays and impacts to the traveling public.

Purpose of This Document

The purpose of this document is to provide a general overview of the practice of traffic control activities associated with incident management and describe various conceptual traffic control elements. Various state laws and policies are in place for the purpose of addressing the safe, quick clearance of incidents. All potential responders have responsible roles in providing immediate and emergency traffic control, with these actions coordinated through the ICS team commander, to eliminate confusing or conflicting actions.

The traffic control elements and applications dealing with incidents can be found in Part 6 of the Manual on Unified Traffic Control Devices (MUTCD). 2 Should an incident be expected to exceed a 30 minute time frame, the required traffic control should replicate, as much as feasibly possible, the requirements of an applicable temporary work zone set-up as found in the MUTCD or comparable state documents. This approach is based on the proven concept that traffic control applications should be in sync with driver expectancy. The MUTCD as well as state and local government supported manuals address the expected standards for all the various types of work zone traffic control requirements, including emergency incidents. The MUTCD has either been adopted as the state standard or serves as the framework for individual state manuals. In addition to these guidelines, there are a number of supporting enhancements to assist and improve the reach of traffic control efforts with the goal of improving safety and facilitating the quick clearance of incidents.

Target Audience

The information provided in this guidebook is directed toward operations personnel, and first and secondary responders who are responsible for establishing, maintaining, monitoring, modifying, and removing any traffic control at an incident scene.

Operations personnel are typically associated with departments of transportation whose response priorities focus on restoration of normal traffic flow. They may implement on-scene traffic control strategies for quick clearance and, once preliminary traffic control is in place, support clean-up and recovery efforts so that the scene is cleared and traffic delays are minimized. These personnel may be dedicated to providing emergency traffic control and intervention, such as the freeway service patrol staff, or in-house staff, such as maintenance personnel, whose skills include providing traffic control for routine operations. The information will benefit this group by providing them with an understanding of available techniques and devices for on-scene traffic control. It will also highlight the benefits of proper incident scene traffic control.

First responders are just that —the first individuals to arrive at the incident scene. They provide the initial response to assist crash victims and isolate and protect the scene by implementing immediate traffic control. First responders typically include law enforcement, fire-rescue, and emergency medical service. Their priority is the safety of motorists, victims, and other responders; their attention is directed to traffic flow only after addressing immediate life threatening needs. The information in this guidebook will provide first responders with a basic understanding of the need to initiate traffic control to secure and protect an incident scene along with the responding personnel.

Secondary responders are those individuals who take over certain incident scene responsibilities, such as traffic control set-up, from first responders and operations personnel; they are not generally first on the scene. Secondary responders provide support functions to assist in the incident response. Typically, their focus is traffic control and management. Operators at traffic management centers could also be included in this group. They can monitor and report immediate and adjacent traffic conditions to the on-scene responders. Some centers also have the capability to identify and / or broadcast information on acceptable diversion routes. They could also be capable of remotely adjusting the timing of adjacent signals to address traffic flow. This group will be able to utilize the guidebook as a reference to the required maintenance of traffic from on-going scene control to the recovery of traffic control as the scene changes and clears.

Structure of this Guidebook

This guidebook is one in an Information Series on Traffic Incident Management Safe, Quick Clearance. This guidebook focuses on Traffic Control Concepts for Incident Clearance. Other guidebooks available in this information series deal with the following topics:

  • Traffic Incident Management in Construction and Maintenance Work Zones,
  • Hazardous Materials Spills in Incident Clearance,
  • Information Sharing for Traffic Incident Management, and
  • Traffic Incident Management Resource Management.

This document discusses various aspects of traffic control for incidents with the focus on the traffic control roles and responsibilities of the responders as well as the safety of the responders and the motoring public. It also recognizes that active traffic management is necessary to meet the fluctuating needs of the incident scene and to minimize clearance and recovery time. Chapter 2 provides an overview of popular state laws and policies enacted to support safe, quick clearance. Chapter 3 addresses the roles/responsibilities of the various categories of responders. Chapter 4 looks at the assignment and responsibilities within the ICS team under the National Incident Management System. Chapter 5 discusses some of the available traffic control tools. Chapter 6 focuses on the affects on traffic control created by the dynamic nature of incident clearance; while Chapter 7 deals with the last stages of traffic control removal and recovery. Chapter 8 highlights some “best practices” to enhance traffic control implementation. Chapter 9 contains references and other suggested readings that were used to develop this guidebook.