Traffic Signal Preemption 

for Emergency Vehicles

Traffic Signal Preemption 

for Emergency Vehicles

A CROSS-CUTTING STUDY

Putting the Putting the “First” in “First Response” “First” in “First Response”

January 2006
Notice

The Federal Highway Administration provides high-quality information to

serve Government, industry, and the public in a manner that promotes

public understanding. Standards and policies are used to ensure and

maximize the quality, objectivity, utility, and integrity of its information.

FHWA periodically reviews quality issues and adjusts its programs and

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i

Dear Reader,

We have scanned the country to bring together the collective wisdom

and expertise of transportation professionals implementing Intelligent

Transportation Systems (ITS) projects across the United States.This

information will prove helpful as you set out to plan, design, and deploy

ITS in your communities.

This document is one in a series of products designed to help you

provide ITS solutions that meet your local and regional transportation

needs. We have developed a variety of formats to communicate with

people at various levels within your organization and among your

community stakeholders:

• Benefits Brochures let experienced community leaders explain in

their own words how specific ITS technologies have benefited their

areas.

• Cross-Cutting Studies examine various ITS approaches that can be

used to meet your community’s goals.

• Case Studies provide in-depth coverage of specific approaches being

taken in communities across the United States.

• Implementation Guides serve as “how to” manuals to assist your

project staff in the technical details of implementing ITS.

ITS has matured to the point that you are not alone as you move

toward deployment. We have gained experience and are committed to

providing our state and local partners with the knowledge they need 

to lead their communities into the future.

The inside back cover contains details on the documents in this series, 

as well as sources to obtain additional information. We hope you find

these documents useful tools for making important transportation

investment decisions.

Sincerely,

Jeffrey F. Paniati

Associate Administrator for Operations

Acting Program Manager, ITS Joint Program Office

Federal Highway Administration

Foreword

Marilena Amoni

Asssociate Administrator for Program

Development and Delivery

National Highway Traffic Safety

Administration

iii

Contents

EXECUTIVE SUMMARY................................................................................1-1

INTRODUCTION............................................................................................2-1

EVP - WHAT ARE THE BENEFITS?.................................................................3-1

IMPROVED RESPONSE TIME ................................................................................................3-1

IMPROVED SAFETY AND REDUCED LIABILITY...................................................................3-1

COST SAVINGS IN FIRE/RESCUE AND EMS PLANNING.......................................................3-2

COST SAVINGS ON FIRE INSURANCE PREMIUMS...............................................................3-3

EVP - WHO IS USING IT?...............................................................................4-1

EVP - WHAT ARE THE TECHNOLOGY OPTIONS?........................................5-1

LIGHT AND INFRARED SYSTEMS .........................................................................................5-1

SOUND-BASED SYSTEMS......................................................................................................5-2

RADIO-BASED SYSTEMS.......................................................................................................5-3

EVP - WHO SHOULD BE INVOLVED? ...........................................................6-1

FORMING THE STAKEHOLDER GROUP ...............................................................................6-1

EVALUATING THE NEED FOR INTEROPERABILITY .............................................................6-1

SITE STUDY DESCRIPTIONS.........................................................................7-1

SITE SELECTION .....................................................................................................................7-1

FAIRFAX COUNTY, VIRGINIA................................................................................................7-2

PLANO, TEXAS ......................................................................................................................7-5

ST. PAUL, MINNESOTA..........................................................................................................7-8

CROSS-CUTTING FINDINGS .........................................................................8-1

THE BENEFITS OF EVP...........................................................................................................8-1

THE COST OF EVP .................................................................................................................8-3

LESSONS LEARNED ......................................................................................9-1

OVERCOMING INSTITUTIONAL ISSUES ...............................................................................9-1

PUBLIC ACCEPTANCE............................................................................................................9-1

EV DRIVER TRAINING ...........................................................................................................9-1

SYSTEM INSTALLATION ........................................................................................................9-1

SYSTEM MAINTENANCE.......................................................................................................9-2

CONCLUSION..............................................................................................10-1

RESOURCES.................................................................................................11-1

FEDERAL AND STATE GUIDELINES ON EVP IMPLEMENTATION......................................11-1

RESPONSIBILITIES IN EVP DEPLOYMENT, OPERATIONS, AND MAINTENANCE .............11-1

INFORMATION ON ORGANIZING, PLANNING, DEPLOYING, AND OPERATING EVP.....11-1

ADDITIONAL RESOURCES .........................................................................12-1

LIST OF FIGURES

Figure 1 - Generalized Flashover Curve for Residential Construction.................................3-2

Figure 2 - Various Light-Based Emitters in Use Today ...........................................................5-1

Figure 3 - Wire and Mast Arm Mounted Light-Based Detectors.........................................5-2

Figure 4 - Sound-Based Detection Equipment in Loudoun County, Virginia.....................5-2

Figure 5 - A Bus and a Hook and Ladder Meet in Alexandria, Virginia Without EVP......6-1
Figure 6 - Typical Intersection in Plano, Texas During Morning Rush Hour .......................7-5

Figure 7 - A St. Paul Signal in the Preemption Phase..........................................................7-10

Figure 8 - Summary of Benefits by Site...................................................................................8-1

Figure 9 - A Ladder Truck Without EVP Pushes Through a Queue at a Red Signal..........8-2

Figure 10 - A Technician Oversees Contract EVP Maintenance............................................9-3

LIST OF TABLES

Table 1 - Cardiac Arrest Survival Factors as a Function of Time.......................................3-3

Table 2 - Summary of EVP Technology Features ...............................................................5-3

Table 3 - Potential Stakeholders and Roles........................................................................6-2

Table 4 - Summary of Interoperability Considerations .....................................................6-3

Table 5 - EVP Site Overview.................................................................................................7-1

Table 6 - Typical Costs of EVP Equipment ..........................................................................8-3

Contents

iv
1-1

The sudden appearance of an emergency vehicle en route to an

emergency can be extremely disruptive to nearby vehicles as individual

drivers maneuver to get out of the way. Some drivers become confused

and create conflicts that can cause emergency vehicle crashes or block

lanes increasing response times. Using Intelligent Transportation Systems

to provide emergency vehicles a green light at intersections can reduce

driver confusion, reduce conflicts, and improve emergency response

times.

This cross-cutting study identifies issues associated with emergency

vehicle operations and emergency vehicle preemption. This study

reports information gathered during a review of publications and site

visits to three jurisdictions operating emergency vehicle preemption

systems. The purpose of this study is to increase awareness among

stakeholders—including police, fire, rescue and emergency medical

services (EMS)—about the benefits and costs of emergency vehicle

preemption. Benefits of emergency vehicle preemption systems include

the following:

• Emergency vehicle preemption has allowed Fairfax County, Virginia

to reduce its response times. The system permits emergency vehicles

along U.S. 1 to pass through high volume intersections more quickly

with fewer conflicts, saving 30 to 45 seconds per intersection. 

• Emergency vehicle preemption in the City of Plano, Texas has

dramatically reduced the number of emergency vehicle crashes -

from an average of 2.3 intersection crashes per year to less than one

intersection crash every five years. 

• In addition, due to reduced delays at signalized intersections, the City

of Plano can achieve the same response times with fewer fire/rescue

and EMS stations than would normally be required, providing

significant cost savings. The city has maintained a response time goal

achievement rate of over 90 percent, contributing to its Insurance

Services Office Class 1 Fire Suppression Rating - the highest possible

rating on a scale from 1 to 10. 

• Emergency vehicle preemption installed in St. Paul, Minnesota has

permitted police, fire/rescue, and EMS vehicles to reach the scene of

an incident faster and with a reduced chance of a crash. Crash rates

per emergency vehicle responses were dramatically reduced in the

years following deployment. 

This study also identifies major lessons learned to guide others in

achieving similar benefits. The following list highlights some of these

elements critical to successful emergency vehicle preemption deployment.

• Emergency vehicle preemption systems can benefit many stakeholders,

including police, fire/rescue, EMS, and transit operators (if transit

signal priority is also provided). To make sure that the needs of all

these stakeholder groups are met, it is important to involve all

stakeholders in a formal and collaborative manner.

Executive Summary
1-2

• A champion, be it an individual or an organization, is often key to

success. At all three sites visited, the preemption initiative

progressed when one person or one group of people provided

leadership and sponsorship of the effort. In some cases, a different

stakeholder took the role of champion as the initiative progressed.

Therefore, it is important that the role of champion is clearly

identified throughout the process. 

• Stakeholders should consider emergency preemption as part of a

developing local ITS architecture. In doing so, it may be possible to

leverage funding for the emergency vehicle preemption system by

sharing costs with other ITS-based emergency response, congestion

management, and clean air attainment programs. Broader

stakeholder groups and a wider range of funding options increase

the potential for successful deployment.

• Signals near emergency facilities (i.e., hospitals, trauma centers, and

fire/rescue and EMS stations) will be preempted more often than

others and drivers may experience delays if multiple preemption

events occur during a short period of time. Each of the sites

indicated that the public accepted these delays and that a public

awareness campaign highlighting the public safety benefits of

preemption was a key factor in reducing preemption-related

complaints.

• It is critical to identify one agency that is responsible for system

maintenance. A clear method for reporting system problems and

well known lines of communication among all involved is required to

avoid delay in making any necessary adjustments or repairs. Effective

maintenance programs ensure that the system provides the highest

degree of benefit.

• A green light is not guaranteed. Emergency vehicle drivers need to

use caution not to over-rely on the system and need to be prepared

to stop if provision of the preemption phase is delayed (i.e., awaiting

time out of an in-progress pedestrian phase). Emergency vehicle

preemption operation and limitations must be a part of initial and

recurring emergency vehicle driver training. 

The purpose of this study is to enable jurisdictions to benefit from the

composite experience of others in an effort to reduce the time required

to move from a good idea to real improvements in the delivery of

emergency services. 

Executive Summary
A key issue facing localities in the U.S. is the challenge that rapid growth

in populated areas places on the fire/rescue and EMS community.

Constrained by tight budgets, officials must make decisions on how to

provide appropriate levels of service while at the same time coping with

increasing demand for services and increasing congestion levels. 

Emergency vehicles (EVs) operating in higher congestion levels are at

higher risk for involvement in crashes and are subject to unpredictable

delays in reaching the scene of a fire or crash. One means to offset the

effects of congestion is the installation of emergency vehicle

preemption (EVP) equipment at signalized intersections. This ITS

technology provides a special green interval to the EV approach while

providing a special red interval on conflicting approaches. 

The concept of EVP and the potential benefit of preemption control to

support emergency response is nearly as old as the traffic signal itself. In

1929, the American Engineering Council published Street Traffic Signs,

Signals, and Markings,1 which included a subsection Emergency Control

in the section on Street Traffic Signals: “In any coordinated system

supplemental arrangements may be provided for breaking the system

into small units for emergency operation, such as runs of fire

apparatus.”

Over the years, various concepts have been developed to provide the

emergency control described in the 1929 document. Several systems

were deployed that created a pre-programmed “green wave,”

providing a progressive green display for the EVs based on the station

of dispatch, the response location, and the use of pre-determined

emergency response routes. 

In the late 1960s, technologies became available to provide emergency

control using vehicle-based emitters and signal-based detectors that

allowed the EVs to preempt the signals as they were approached. Many

communities invested in these systems in an effort to reduce the

number of EV crashes. Some cities committed to the deployment of EVP

on 100 percent of their signals, retrofitting hundreds of signals and

including the technology on all new ones. Other growing communities

committed to the technology early in their growth cycles and integrated

EVP on every new signal as the community grew.

The material presented in this cross-cutting study is derived primarily

from two types of sources: written sources and interviews. Interviews

were conducted at three sites—Fairfax County, Virginia; Plano, Texas;

and St. Paul, Minnesota—that were selected to show a wide range of

EVP deployment options, including jurisdiction size, scope of EVP

deployment, jurisdictional responsibilities, and the use of the system by

police and transit. Individuals interviewed include local policy makers,

2-1

Introduction

1 American Engineering Council (1929). Street Traffic Signs, Signals, and Markings.
fire chiefs, transportation and traffic engineers, fire/rescue and EMS

vehicle drivers, police officers, and signal system technicians. This study

includes a summary of the experience for the three sites with regard to

the benefits experienced, costs incurred, and lessons learned. 

The purpose of the study is to enable other jurisdictions to benefit from

the composite experience of others in an effort to reduce the time

required to move from a good idea to real improvements in the delivery

of emergency services.

Introduction

2-2
EVP systems are designed to give emergency response vehicles a green

light on their approach to a signalized intersection while providing a

red light to conflicting approaches. The most commonly reported

benefits of using EVP include improved response time, improved safety,

and cost savings. These benefits have been realized since the early

deployments of EVP and have been documented since the 1970s.

Selected key findings are summarized here. Later in this report, these

findings are echoed by the jurisdictions that are visited as part of the

EVP study. 

EVP can improve EV response times by reducing the probability that

responding EVs will arrive at intersections during the red signal phase

and encounter significant queues. In highly congested areas, EVs may

encounter extended queues that force them to slow to a crawl, adding

seconds or minutes to the time required to reach the scene of an

incident. A green light gets the queue moving and the traffic dispersed

before the EV arrival allowing the EV to maintain higher average speeds

than would be expected given intersection spacing along the route and

normal traffic conditions.

In 1978, the City of Denver Department of Safety produced a study2

reporting changes in EV response times as a result of signal preemption.

The study was conducted over a 90-day period in an area involving

three fire stations and 75 signalized intersections. Firefighters recorded

travel times necessary to traverse typical routes before and after

preemption installation. The data showed EV response times decreased

by 14 to 23 percent, with savings of approximately 70 seconds per

response on a route with three to six signalized intersections. 

EVP can reduce the chance of an EV crash at a signalized intersection.

Nationwide, over the past 10 years, more than 25 percent of all EV

crashes have been found to occur at signalized intersections.3 These

crashes often involve situations where vehicles approaching a green

signal cannot see an EV approaching on the intersecting roadway

because of line-of-sight problems with nearby buildings, vegetation, or

hills. For these situations, EVP provides familiar guidance to private

vehicles by showing a red signal at the conflicting approaches, thereby

bringing these vehicles to an orderly stop. Safety benefits can be

measured by comparing EV crash histories or, as a surrogate, by

measuring the reduction in number of and severity of conflict points

3-1

EVP—What Are the Benefits?

Improved

Response Time

Improved Safety

and Reduced

Liability

2 City of Denver Department of Safety (1978). Time Study on the Effectiveness of the Opticom Traffic

Control System (Year 1978), report prepared for the City of Denver by the Denver Department of

Safety, FHWA Report No. D-ORTS/78.5.

3 U.S. DOT (2003). Fatality Analysis Reporting System (FARS) Web-Based Encyclopedia Queries for

Emergency Use Crash Statistics. http://www-fars.nhtsa.dot.gov.
3-2

EVP—What Are the Benefits?

Figure 1 – Generalized Flashover Curve for Residential Construction8

that may be present at the time when an EV traverses the intersection.4

A decrease in EV crashes reduces public liability associated with fatalities,

injuries, and property damage. Over the past 10 years, there have been

approximately 80 EV crashes each year in the U.S. that involve fatalities.5

In 1977, at the request of city officials, St. Paul’s fire chief conducted a

pre-and post-EVP safety impact analysis.6 The fire chief studied EV

crashes before and after the EVP system deployment, and reported on

the preemption deployment rate and the crash histories. Over the

period from 1967 through 1976, the City of St. Paul deployed

preemption on 285 of 308 intersections. During this period, the number

of EV crashes decreased from the 1967 high of eight to an average of

3.3 per year in the latter years of the study. 

As EVP systems have the potential to improve response times and safety,

this trend can translate into cost savings for the community. Response

times for fire/rescue and emergency medical services are important

measures of effectiveness for local public safety departments and are

key elements in fire/rescue and emergency medical service planning. In

defining service needs, jurisdictions consider fire flashover7 times (Figure

1) and survival rates for cardiac patients (Table 1) along with a study of

local conditions, including development density and loss potential. ITS

solutions, such as EVP, can lead to improved EV response times

increasing the effective service radius of a single station.

Cost Savings in

Fire/Rescue and

EMS Planning

4 Louisell, William C., Collura, John, and Tignor, Samuel C. (January 2003). Proposed Method to

Evaluate Emergency Vehicle Preemption and Impacts on Safety, Paper presented at the 82nd

Annual Meeting of the Transportation Research Board, Washington, D.C.

5 U.S. DOT (2003). Fatality Analysis Reporting System (FARS) Web-Based Encyclopedia Queries for

Emergency Use Crash Statistics. http://www-fars.nhtsa.dot.gov.

6 Fire Chief, Department of Fire and Safety Services, St. Paul, Minnesota, Emergency Vehicle Accident

Study (Year 1977), a letter written from the Fire Chief to a City Councilman, 1977.

7 The National Fire Protection Association Handbook defines “flashover” as the point when “all

combustibles in the space have been heated to their ignition temperature and spontaneous

combustion occurs.”

8 National Fire Protection Association (2001). NFPA 1710 - Standard for the Organization and

Deployment of Fire Suppression Operations, Emergency Medical Operations, and Special

Operations to the Public by Career Fire Departments.

Generalized Flashover Curve

Temperature in Degrees F

Minutes

3 5 7 9 11

1,500

800

200

Flashover Temperature

Exact point depends 

on contact time and 

heat potential of materials

The goal is to 

extinguish the fire

before this point
3-3

For example, Loudoun County, Virginia is one of America’s fastest

growing counties.10 As such, the county evaluates its current and future

fire/rescue and emergency medical service plans given the county’s rapid

transition from a rural area to a mixed-use area. The influx of new

population centers and the increase in congestion on arterial roadways

challenge the county. In a January 2003 study,11 the county examined

future fire/rescue and emergency medical service plans identifying the

parameters to be considered in selecting the number of stations, the

location of the stations, and the required number and type of apparatus

that will be required. One of the key considerations in the planning

process is average EV operating speed and the effective service radius

given response time goals.

Improved response times can lead to an improvement in the insurance

industry ratings of a community’s fire suppression service, with a

corresponding reduction in fire insurance rates for residential and

commercial property owners. The Insurance Services Office (ISO),

through its Public Protection Classification (PPC) program, assigns

insurance ratings to each participating community once every 10 years.12

By classifying a community’s ability to suppress fires, the ISO helps the

communities evaluate their public fire protection services and plan

improvements. The ratings are very important to communities as they

pursue growth and economic development plans. Some communities,

such as the Town of Blacksburg, Virginia have reported that its ISO Class

had been raised reflecting the response time improvements made

possible by EVP deployments.13

EVP—What Are the Benefits?

Cost Savings on

Fire Insurance

Premiums

Time Until Defibrillation Survival Chances

With every minute... Chances are reduced by 

7 – 10%

After 8 minutes... Little chance of survival

Table 1 – Cardiac Arrest Survival Factors as a Function of Time9

9 American Heart Association Website (2004). http://www.americanheart.org.

10 U.S. Census Bureau Website (2004). http://www.census.gov.

11 Loudoun County Public Safety Service Planning (2003), EMSSTAR Final Service Plan.

http://www.loudoun.gov/fire/index.html.

12 Insurance Services Office Website (2004). http://www.isomitigation.com

13 Town of Blacksburg, Virginia (2000). Annual Report for the Year 2000.

Blacksburg, Virginia

was able to raise its

ISO Class, reflecting

the response time

improvements made

possible by EVP

deployment.

EVP systems are deployed and operating across the U.S. In fact, the 

U.S. DOT ITS Deployment Statistics website,14 which tracks ITS

deployment in the country’s largest metropolitan areas, indicates that

there are over 30,964 signals equipped with EVP technology in 375

separate jurisdictions. About 20 percent of traffic signals in the 78

largest metropolitan areas are equipped with EVP.

The scale and patterns of EVP deployments seen in individual jurisdictions

across the country cover a broad range. The number of signals and the

specific signals equipped depend on the issues and problems faced. Some

jurisdictions have equipped only a few signals in an effort to provide safe

and efficient arterial access from fire/rescue, EMS, and police stations

located on side streets. Many others have used the systems to address

arterial access as well as to address known problem intersections. Some

jurisdictions have adopted policies of 100 percent coverage across the

entire jurisdiction or in selected downtown areas.

Most of the jurisdictions that reported 100 percent EVP coverage are

located on the fringe of older, major metropolitan areas and report that

they own and operate signal systems of 150 signals or less. As these

communities began to grow into suburbs, EVP was adopted as an

integral component of the public safety and traffic control development

plans at any early point in the growth cycle with stakeholders

committed to policies to equip 100 percent of the signals. In cases

where existing signals were not equipped with EVP, signal systems were

brought up to a 100 percent deployment level over several years using

bonds or other capital improvement project funding mechanisms. Once

at the 100 percent level, these jurisdictions enacted policies requiring

that each new signal be installed with EVP.

4-1

EVP—Who Is Using It?

14 U.S. DOT’s ITS Deployment Statistics Website (2005). http://www.itsdeployment.its.dot.gov.

“Electing to equip 100

percent of the signals

was a natural choice

for Plano. As a part of

its vision and

comprehensive

development plan, the

city committed to

using technology as a

a cost-effective means

to develop the highest

possible standards of

service across the

board. EVP was one

of those choices.”

– Lloyd Neal

Transportation Engineering

Manager, City of Plano

5-1

There are many EVP technologies being employed today including lightbased, infrared-based, sound-based, and radio-based emitter/detector

systems. As such, stakeholders must gather information and consider key

operational features and interoperability requirements as they plan

deployments and recommend EVP technology approaches. This section

provides an introduction to key operational features that may be useful

in assessing the available approaches. 

Light and infrared systems employ emitters that are normally mounted

on the roof of the EV and are operated in conjunction with the

emergency lights (Figure 2). The photograph on the left shows an early

optical emitter mounted just under the windshield. The upper right

photograph shows a factory-mounted emitter in front of the light bar.

The lower right photograph shows a locally-installed emitter on the

roof of a cab. The emitter system includes the light unit and a power

supply that is located inside the vehicle.

EVP—What Are the Technology Options?

Light and

Infrared Systems

Figure 2 – Various Light-Based Emitters in Use Today

On the power unit, there is typically a control panel that allows

selection of a high priority mode (used for EVP), and a low priority

mode (used for transit signal priority). The control panel also includes a

feature to assign unique codes to each vehicle operating on the system.

The codes provide a record of which operator drove the vehicle, as well

as protect against unauthorized use. Light- and infrared-based detectors

are generally mounted on the signal arm. Mounting requirements

include provisions for power and communications cables. Figure 3 shows

both wire and mast arm mounted light-based detectors. Some
jurisdictions install confirmation lights in conjunction with the detectors.

This light provides feedback to the EV driver that the request for

preemption has been received and that the request will be served

according to the local preemption transition protocol.

5-2

EVP—What Are the Technology Options?

Figure 3 – Wire and Mast Arm Mounted Light-Based Detectors

Sound-based systems use the EV siren as the emitter. The waveform of

the siren is loaded into the detection and processing equipment such

that directional

microphones mounted on

the signal arm can detect

sirens that meet the

Federally mandated decibel

level of 1,200 db. Once

detected, the siren

waveform is verified, a

preemption request is

generated by the phase

selector and sent to the

signal controller.15 Figure 4

shows sound-based

detection equipment on a

signal pole in Loudoun

County, Virginia. The

system pictured serves a

regional hospital with EVP

on two approaches.

Figure 4 – Sound-Based Detection

Equipment in Loudoun County, Virginia

Sound-Based

Systems

15 Collura, J., and Willhaus, E.W. (June 2001). Traffic Signal Preemption and Priority: Technologies,

Past Deployments, and System Requirements. Paper published in the conference proceedings of

the ITS America 11th Annual Meeting, Miami Beach, Florida.
5-3

EVP—What Are the Technology Options?

Radio-based systems utilize a receiver with an omni-directional antenna

to detect a digitally coded spread spectrum or narrow band radio

transmission from an EV. In these systems, the direction of preemption is

selected in the vehicle and direction-unique signal is transmitted to the

intersection. Radio-based systems avoid the line-of-sight limitations

associated with light- and infrared-based systems. Once a radio

frequency pulse is detected and the proper direction of travel is

determined, the preemption request is processed by the phase selector

and the signal controller.

Table 2 summarizes the technical considerations of the various EVP

options.

16 Collura, J., and Willhaus, E.W. (June 2001). Traffic Signal Preemption and Priority: Technologies,

Past Deployments, and System Requirements. Paper published in the conference proceedings of

the ITS America 11th Annual Meeting, Miami Beach, Florida.

Technology 

Consideration

Strobe 

Activated

Siren 

Activated

Radio 

Activated

Dedicated Vehicle 

Emitter Required

Yes No Yes

Susceptible to Electronic 

Noise Interference

No No Yes

Clear Line of Sight 

Required

Yes No No

Affected by Weather Yes No No

Possible Preemption of 

Other Approaches

No Yes Yes

Radio-Based

Systems

Table 2 – Summary of EVP Technology Features16

6-1

EVP—Who Should Be Involved?

Forming the

Stakeholder

Group

Evaluating the

Need for

Interoperability

A key step in planning, deploying, and operating EVP systems is the

formation of a stakeholder group. The first question is,“Who should be

involved?” and the second is,“Who needs to talk to whom, i.e., what

are our interoperability needs?” 

Stakeholder group membership depends on the individual jurisdiction—

its governmental organization, the division of responsibilities for signal

operation and maintenance, jurisdiction membership in regional

Councils of Government (COGs), and participation of Citizen Action

Committees (CACs). Table 3 lists the potential agencies and groups that

may be included in a stakeholder group and indicates the roles each

may have in the planning, installation, operations, and maintenance of

EVP systems.

Interoperability may be a key consideration in the selection of a

particular EVP technology as the stakeholders identify the functional

requirements of their own system and the requirement to support other

neighboring jurisdictions as part of larger emergency response networks

and mutual aid agreements. The following interoperability

considerations may be useful to consider in selecting the best

technology for a particular EVP application. 

• Participation in a regional emergency response network may lead

stakeholders to consider how the EVP system would be used within the

jurisdiction and across jurisdictional lines in the case of a large-scale

regional emergency response. Certain routes within the region may be

equipped with a particular technology to support travel to sites for

which large-scale emergency response plans have been developed.

Figure5 – A Bus and a Hook and Ladder Meet in Alexandria, Virginia

Without EVP
6-2

EVP—Who Should Be Involved?

Stakeholder Responsibility

City or County Fire/Rescue 

and/or EMS Departments

• Generally the proponents for the initiative

• Often key players in seeking Federal and state emergency

response improvement funds

City or County Police

Departments

• Potential co-proponents, where police use is considered

City or County Transportation

or Public Works

Department

• Integration with local transportation planning efforts 

including transit signal priority

• Often a key player in seeking Federal and state 

transportation improvement funds

City or County Planning

Department

• Integration with growth and development plans

City or County Traffic

Operations Department 

(if applicable)

• Planning, integration, testing, and installation 

• Supporting operations, including system access 

permissions and system event record keeping

• Developing and supporting execution of maintenance 

concepts

City or County Executive

Risk Management 

(if applicable)

• Identifying the impact on loss rates suffered in EV crashes

• Identifying the liability associated with delayed emergency

response

• Identifying liability issues associated with EVP operations

City or County Disaster

Response or Homeland

Security Departments 

(if applicable)

• Potential co-proponents for the initiative 

• Often key players in seeking Federal and state emergency

response improvement funds

State Department of

Transportation

For jurisdictions that do own and operate their own 

signal systems:

• Integration of local signal operations with state operated

and maintained systems

For jurisdictions that do not own and operate their own 

signal systems:

• Planning, integration, testing, and coordinating for 

installation

• Supporting operations, including system access 

permissions and system event record keeping

• Ensuring development of maintenance memoranda of

agreement with the agency that owns the EVP equipment

and supporting execution of maintenance concepts

Council of Governments

Representative

• Act as coordinator with other jurisdictions within the 

participating region, identifying interoperability issues and

cost-sharing opportunities

Citizens Action Committee

Representative

• Act as a proponent for improved public safety

• Help promote public awareness

Table 3 – Potential Stakeholders and Roles
• Memberships in mutual aid agreements may require that all users of

the system have access to systems in neighboring jurisdictions to

facilitate mutual aid coverage in fringe areas or to access specialized

apparatus when required. 

• Planned or future transit signal priority should be considered as a

means to develop a larger stakeholder base and to spread the costs

among a wider group that has access to a variety of funding sources

such as those committed to congestion management and clean air

attainment. Figure 5 illustrates the need for coordination of efforts

as public safety and transit agencies work with transportation and

traffic officials as they plan signal system enhancements. 

• Many localities invest in EVP as a way of speeding access to regional

medical facilities. However, these facilities are often served by

emergency vehicles from several different jurisdictions. If the purpose

of the EVP system is solely to provide access to these medical facilities

and will only be installed at intersections approaching them, then a

sound-based system may be the best option. Using this technology, EVs’

own sirens activate the signal preemption system so no special

equipment is required on the vehicles. 

Table 4 shows the impact of interoperability conditions on the usability

of various EVP technology options.

6-3

EVP—Who Should Be Involved?

Will Technology Meet Level of Interoperability Desired?

Level of 

Interoperability

Light or Infrared 

Strobe Activated

Siren 

Activated

Radio 

Activated

Emergency 

Response 

Route

Yes, equip all 

participants

Yes Yes, equip all 

participants

Mutual Aid 

Agreement

Yes, equip all 

participants

Yes Yes, equip all 

participants

Transit Signal

Priority

Yes, equip all 

participants

No No

Regional 

Medical Center

Yes, equip all 

participants

Yes Yes, equip all 

participants

Table 4 – Summary of Interoperability Considerations

Three sites—Fairfax County, Virginia; the City of Plano, Texas; and the

City of St. Paul, Minnesota—are featured in this section. They represent

a range of system maturity, stakeholder relationships, signal operating

concepts, and deployment and operational approaches.

As of 2004, Fairfax County was in the process of equipping selected

corridors within a large, highly integrated regional traffic signal system.

Plano, Texas has a 20-year history of operating EVP across 100 percent of

its signals, which were equipped incrementally as part of a

comprehensive growth plan. St. Paul has over 25 years of operating

experience across 100 percent of its signals, which were equipped

retroactively as part of a multi-year EVP deployment plan. Table 5

provides a snapshot of key characteristics of each site.

This section presents each site’s EVP deployment and operations

experience in terms of the history of the deployment, the site’s traffic

operations conditions, the emergency services operational environment,

and the operation and maintenance concepts. 

7-1

Site Study Descriptions

Site Selection

Site Characteristics Fairfax County, VA Plano, TX St. Paul, MN

Area (Mi2) 497 76 53

Equipped Signals/

Total Signals

37/1,034* 194/194 368/368

Signal Controller Type Type 170 Type 170† Type 170

Central Signal Control

Center

Yes Yes Yes

Signal Operations Mode Semi-actuated Semi-actuated Semi-actuated

Communication with

Signals

Twisted copper

phone lines

Wireless Twisted copper

phone lines

Preemption Technology

Employed

Vehicle-based light

emitter

Vehicle-based light

emitter

Vehicle-based light

emitter

EV Classes Served Fire/rescue and 

EMS

Fire/rescue and 

EMS

Fire/rescue, EMS,

and police

Transit Priority Yes No No

Table 5 – EVP Site Overview

* The signals in Fairfax County are part of the Virginia Department of Transportation (VDOT)

Smart Traffic Signal System that is a highly integrated system operating across three Northern

Virginia counties.

† The City of Plano, Texas operated Type 170 controllers at the time that interviews and site visits

were conducted for this study. However, the City upgraded to Type 2070 controllers in 2004.
Fairfax County is one of four counties that make up the Northern

Virginia region. The county covers an area of 407 square miles with a

population of approximately one million.17 The county seat is located

approximately 12 miles southwest of Washington, D.C. Development in

the county is diverse, ranging from high density office complexes,

technology campuses, and commercial development to residential areas

that range from medium rise apartments and town homes to single

family homes in neighborhoods and rural acreage settings. 

Fairfax County has been a leader in the regional push for EVP that first

started in the mid-1980s. During this period, fire/rescue and EMS chiefs

across Northern Virginia’s four counties identified EVP as a means to

offset the negative impact that growing congestion was having on EV

response times and on EV crash potential. Since the concept was first

introduced, EVP in Fairfax County has been deployed in several distinct

phases. In the first phase, the county installed EVP on signals that

provide arterial access from off-street stations. The second phase

consisted of installation of EVP on problem intersections on a case-bycase basis. The third phase consisted of installation of EVP on a small

number of intersections located downstream from arterial access points

equipped in the first phase (typically one or two intersections). Success

in these deployments led to a larger initiative to expand EVP to support

EV operations on a corridor level. 

The proposal to equip arterial signals on a corridor basis emerged in

1997. The initiative did not progress initially because of concerns over

the impact on the operation and performance of the Northern Virginia

Smart Traffic Signal System, operated by the Virginia Department of

Transportation (VDOT). The corridors proposed by fire/rescue and EMS

officials were all high interest corridors from a traffic signal system

operation perspective, as they operate at near saturation conditions

during much of the day. The initiative stalled until the system

champions decided to raise the issue on a regional level within the

signal operations committee of the Washington D.C. Council of

Governments. This action increased the supportive stakeholder base as

county transportation officials became interested in the concept as a

way to support development of advanced public transportation

corridors equipped to provide transit signal priority. 

With a broader stakeholder base and increased momentum, VDOT

proposed a test plan that involved various technologies and operational

concepts. Fairfax County was selected by the U.S. DOT for a test of

integrated EVP and transit signal priority using optical emitter and

detection systems. The test was conducted on a section of U.S. 1 located

just south of Alexandria, Virginia. 

7-2

Fairfax County,

Virginia

EVP Deployment

History

17 U.S. Census Bureau Website (2004). http://www.census.gov.

“With the extremely

high number of

emergency calls for

the U.S. 1 fire and

rescue stations, not to

mention the heavy

traffic volumes in the

background, the

corridor was the

perfect candidate for

emergency vehicle

signal preemption.”

– Doug Hansen

Senior Transportation

Planner, Fairfax County

Site Study Descriptions
The test section was a 1.3-mile stretch of roadway that operated under

heavy traffic load during rush hours. The section had seven signals

operating on six Type 170 controllers. At the mid-point of the test

section, a minor side street intersection provided arterial access for Fire

and Rescue Station 11, which was the busiest station in the county. 

Transit operations on the test section included five fixed-schedule

routes. The local Fairfax Connector operated three of these and the

Washington Metropolitan Area Transit Authority (WMATA) operated

two. During the peak periods, between the two services, buses ran at

10-minute headways through this important transit corridor that serves

both point-to-point riders as well as those traveling by bus to transfer to

the WMATA operated subway. 

In late 2003, the field test results were reviewed. Measures of benefit

and impact indicated that EVP and transit signal priority could be

operated on the busy U.S. 1 corridor. As a result of this report, VDOT

authorized Fairfax County to progress with the installation of EVP and

transit signal priority on all signals on the 13-mile portion of U.S. 1 that

falls within the county. The installation of the newly approved signals

was completed in 2004.

The signals on U.S. 1 in Fairfax County are owned and operated by

VDOT and they are operated as part of a network of over 1,000 signals

serving Northern Virginia. During most of the day, the signals operate in

the semi-actuated mode with offsets programmed to support

progression in peak directions. Rush hour cycle times are typically 180

seconds. At the major intersections, the green time split approaches 67

percent on the arterial and 33 percent on the side streets. During the

morning peak period, queues on the arterial approaches to major

intersections on U.S. 1 typically will be between 12 and 18 vehicles deep

across all three travel lanes and the left turn pockets will be full at

intersections with major side-streets.

EV trip generation in Fairfax County is significant with 90,000

emergency response calls per year. These responses originate from 35

stations that house both fire/rescue and EMS units. The response time

goal for the county is 5 minutes from the time of dispatch for fire

suppression and 6 minutes from the time of dispatch for the arrival of

advanced life support. These goals were set based on National Fire

Protection Association (NFPA) flashover curves and American Heart

Association criteria for responses to cardiac arrest. Fire/rescue and EMS

performance against these and other goals is reported to the county

Board of Supervisors annually. 

At present, the county operates 35 fire/rescue and EMS stations. Each

station is responsible for approximately 11.5 square miles. Each station is

staffed full time by career fire/rescue and EMS personnel, although 11

of the stations also have volunteers. The county’s long-range fire/rescue

and emergency medical service plan calls for 40 stations when the

7-3

Traffic Operations 

on U.S. 1

Emergency Service

Operations

Site Study Descriptions

“Our goal with the

EVP program is to get

our fire and rescue

personnel onto the

roadway safely and to

get them to the scene

as quickly and safely

as possible.”

– Eddie Beitzel,

Fire and Rescue 

Department Planner, 

Fairfax County
county completes development according to its comprehensive plan.

One of the key assumptions in the planning methodology includes

maintaining an average EV speed of 32.6 mph. Fire/rescue and

emergency medical service performance is periodically reviewed as part

of the county’s long range planning effort. These reviews have

highlighted three corridors, including U.S. 1, for which the county plans

to pursue corridor level deployment to offset reductions in average EV

speeds caused by congestion. 

In Fairfax, only fire/rescue and EMS vehicles have access to the full EVP

system. However, transit services operating on the corridor include

approximately six buses per hour during the AM and PM peak periods

that are equipped with the optical emitters. However, transit vehicle

emitters operate on the low priority setting which activates transit

priority based on satisfaction of preset conditions, one of which is to

yield to any EVP request. 

Preemption in Fairfax County is provided only on the arterial approaches

because the EV trip patterns generally include a segment of arterial travel

followed by turnoff on to collector roads, and then turns on to

neighborhood or commercial area streets. The detectors are set to

support a detection range of approximately 1,600 feet except in cases of

closely spaced intersections or where roadside features cause problems

with preemption activation. The goal is to disperse the queues to the

point where the private vehicle drivers can move into the middle and

right lanes allowing the EV to maintain speed in the left. For preemption,

the only condition for request approval is that the signal is not in a

pedestrian phase. All other times, the controller will reference the

transition plan and move from the current phase while honoring

minimum green and amber times.

Once in preemption, the signal displays a green ball or green arrow on

all signal heads on the EV arterial approach. All movements on all other

approaches are brought to a red interval. This phase design is consistent

with displays that drivers normally see on the arterial under normal

semi-actuated operating conditions. 

7-4

Fairfax County,

Virginia, EVP System

Highlights: 

• System first proposed in 1987

• Population of 

1 million

• One high-use corridor equipped—13

miles of U.S. 1

• Two additional

high-interest corridors identified for

future 

deployments

• Used by fire/rescue

and EMS vehicles,

as well as transit

vehicles using lowpriority mode for

conditional transit

signal priority

• 90,000 emergency

response calls per

year

Site Study Descriptions
Plano, Texas, is a suburb located approximately 20 miles northeast of

Dallas. Plano is an incorporated city with a population of approximately

220,000.18 As of 2004, the city size was 74 square miles, although the city

experiences a slow but steady growth due to annexation. Within the

city, land use varies from moderate density residential to commercial

campus development. Light commercial and retail facilities complement

the surrounding residential and commercial campus areas. The

downtown area consists of approximately 16 square blocks made up of

multistory residential apartments, street front stores, and restaurants, as

well as private and public office buildings. 

EVP deployment began in 1984 as the result of an initiative by the fire

chief. The chief had moved to Plano in 1982 from a jurisdiction in Illinois

where he led an effort to equip a small corridor with EVP equipment to

reduce EV crashes. In Plano, the chief wanted to address a high EV crash

rate. Analysis of the EV crash history for the preceding three-year period

indicated that nearly 1/3 of the 22 total EV crashes occurred at

signalized intersections.

In the early 1980s, Plano had a population of approximately 50,000 and

covered approximately 16 square miles. However, growth forecasts and

the city’s master development plan estimated that in the next 20 years,

the population would reach 250,000 and cover approximately 75 to 80

square miles. Keeping this forecast in mind, the fire chief encouraged a

capital improvement bond that could serve as a funding mechanism. To

develop support, the fire chief worked with a citizens’ advisory

committee to develop a fire protection master plan. The advisory

committee and the chief proposed the retrofit of all existing signals and

the inclusion of EVP for all new signals.

The initial deployment to retrofit 46 intersections took three years,

resulting in a 100 percent deployment by 1987. As the city grew, 10 to

17 new signals were installed each year. Each new signal was designed,

priced, and installed with integrated preemption equipment. Plano

continues to have 100 percent preemption coverage.

7-5

Plano, Texas

EVP Deployment

History

18 U.S. Census Bureau Website (2004). http://www.census.gov.

Site Study Descriptions
Traffic patterns in Plano have grown more complex as peak periods

have gotten longer over the past 10 years. Commute patterns have

shifted from primarily morning and evening commutes to and from

Dallas to more random patterns typical of widely distributed points of

origin and destination. The transportation network is made up primarily

of arterial roadways laid out in a grid system. The arterial roadways are

all built in a boulevard fashion so opposing traffic is separated by treelined grass medians bordered by non-mountable curbs (Figure 6).

Multilane queues of up to 22 vehicles long are typical. 

7-6

Traffic Operations 

Emergency Service

Operations

Site Study Descriptions

Figure 6 – Typical Intersection in Plano, Texas, During Morning Rush Hour

Plano owns and operates all 194 traffic signals in its system. Although

Plano originally used Type 170 controllers at each signal, the city upgraded

to Type 2070 controllers in 2004. The city runs a centralized traffic

management and control center that communicates with signal controllers

continuously via wireless transmission. 

The traffic signal timing plan varies throughout the day. During the peak

periods, the signals operate in the semi-actuated mode with offsets to

optimize progression in the peak direction. During non-peak periods, the

signals operate in a semi-actuated mode, free mode, or flashing mode,

depending on the location and the time of day. Major intersections

operate on 160-second cycles and, signals at the minor intersections

operate on 80-second cycles. During the morning peak period, queues on

all four approaches to major intersections will typically be between 18

and 22 vehicles deep with some cases exceeding 30 vehicles. 

EV trip generation in Plano is relatively high with 16,000 emergency

response calls per year from 10 fire/rescue and EMS stations. These

responses generate an average of one preemption request per day per

signal across the city. Some signals, located near hospitals and fire/rescue

and EMS stations, are preempted as many as 15 times in a day or, on

average, once every 90 minutes.

The response time goal for the city of Plano has been set at 90 percent of

calls responded to within 6 minutes, 59 seconds. This goal was set by the
City Council to affirm the city’s commitment to responsive public safety

services. As part of its continuing commitment, the fire chief delivers an

annual summary presentation to the City Council that details the

department’s performance in the preceding year by zone within the city. 

Zones in which the goal is not met are reviewed for potential policy 

or capitalization initiatives to improve the level of service. The city

operates one fire station for every 7.5 square miles of incorporated

area. Eight of the 10 stations operate at normal staffing and equipment

levels. Two stations have additional personnel and equipment assigned

to offset growth and congestion trends in one area of the city under

consideration for a new station. It is expected that one more station will

be built in the near term.

In Plano, only fire/rescue and EMS vehicles have access to the EVP

system. The system was a fire department initiative. Over the 20-year

operational period, neither police nor transit officials have expressed

strong interest in using the system. 

All compatible emitter-equipped vehicles from the surrounding

communities are allowed to access the Plano system. Similarly, Plano’s

emergency vehicles are permitted access to the priority systems of their

neighboring communities. As of 2004, Plano is considering moving

toward encrypted system use due to the appearance on the retail

market of devices that claim to activate EVP for ordinary auto drivers.

Enhancing the system with encryption will require coordination with the

surrounding communities. All Plano emitters are capable of encryption;

however, not all intersections are equipped with detectors capable of

operating in an encrypted mode. Encryption is expected to prevent

unauthorized users from accessing the system in addition to providing a

record of which EVs used the system and when.

Preemption in Plano is provided on all four approaches to each

intersection. This configuration supports the EV trip patterns in which EVs

can proceed to a destination using the grid-oriented arterial road system.

The detectors are set to support a detection range of approximately 1,600

feet unless roadway or roadside features restrict ranges due to line-ofsight problems. The goal is to have a minimum span of 20 seconds

between the call and the arrival of the emergency vehicle at the signal.

For preemption, the only condition for request approval is that the signal

is not in a pedestrian phase. All other times, the controller will transition

from the current phase at the expiration of the minimum green time.

Once in preemption, the signal displays a green ball or green arrow on

all signal heads on the EV approach. All movements on all other

approaches will be brought to a red interval. This phase design is

consistent to displays that are generated on the arterial under normal

semi-actuated operating conditions.

7-7

Preemption System

Operations

Plano, Texas EVP

System Highlights 

• Installation

began in the

mid-1980s

• Population of

222,000

• 100 percent of

signals equipped

• Used by fire/

rescue and EMS

vehicles only

• 16,000 emergency response

calls per year

Site Study Descriptions
The City of St. Paul is one of the two Twin Cities of Minnesota that form

the heart of the largest metropolitan area in the state, with a total

population of nearly 3 million people.19 St. Paul is an incorporated city,

with a population of approximately 288,000 and a land area of 53

square miles. Within the city, land use varies from single-family

neighborhoods, to moderate-density residential and commercial, to a

high-density central business district. The downtown area of St. Paul

consists of approximately 70 square blocks with a variety of multistory

residential apartments, street front stores and restaurants, and high-rise

office buildings, both privately and publicly owned. 

In 1969, EVP was implemented at 28 intersections in St. Paul as the first

step in an effort to reduce the number of EV crashes experienced each

year. Between 1969 and 1976, the city equipped 285 of its 308

intersections with optical EVP systems. Initially, the deployment was only

on the two main approaches to each intersection. This deployment plan

was modified in 1972 after a fatal crash occurred between a police car

and a fire truck at an EVP-equipped intersection. After this incident, the

mayor of St. Paul decided to provide full coverage of the preemption

system to all intersections on all approaches. As of 2004, St. Paul operated

an EVP system on 100 percent of its 368 traffic signals on all approaches.

New traffic signals installed in St. Paul are outfitted with preemption

equipment during construction. 

The transportation network is comprised primarily of major and minor

streets laid out in a grid system. A sub-grid of minor streets between the

arterials provides access to various neighborhoods and commercial areas.

Throughout the city, the streets are bounded on the right side by nonmountable curbs and sidewalks but most do not have raised center

medians. As is the case with many central business districts throughout

the country, the downtown area of St. Paul has short blocks and several

one-way streets. 

St. Paul owns and operates all of the traffic signals that serve the city.

Each signal is controlled by Type 170 equipment from a centralized

traffic management center by the Traffic Operations section of the City

of St. Paul Department of Public Works. The Traffic Operations staff can

monitor signal operations continuously and can send updated signal

timings to intersections through a combination of broadband and

twisted copper wire communication connections. Most signals in the city

operate on a 60-second cycle length. Some of the more heavily traveled

corridors have cycle lengths of 120 seconds. During the peak periods,

the signals typically operate in the semi-actuated mode with offsets to

optimize progression in the peak direction. During non-peak periods,

the signals operate in a semi-actuated mode, a free mode, or in a

flashing mode, depending on the location and the time of day. 

7-8

EVP Deployment

History

Traffic Operations

St. Paul,

Minnesota

19 U.S. Census Bureau Website (2004). http://www.census.gov.

Site Study Descriptions
St. Paul fire/rescue and EMS vehicles respond to approximately 26,000

emergency calls per year from 16 fire/rescue and EMS stations. Fire

suppression responses account for approximately 12,500 of these calls;

emergency medical services account for the remaining 13,500 calls, with

an average of approximately 70 emergency response calls per day, or

about one call every 20 minutes.

In contrast to Fairfax County and Plano, the City of St. Paul EVP system is

used by the police department as well as fire/rescue and emergency

medical services. The inclusion of police as system users places a

significantly higher demand on the system. Police receive 263,000 calls

annually, with an average of 720 calls per day or, one police response

every 2 minutes. In addition to the increased demand, police use of the

system differs from fire/rescue and EMS in trip origin and travel route

patterns. While fire/rescue and emergency medical services primarily

respond from fixed stations and travel along predictable routes, police

vehicles respond from random locations and make route choices quickly

as police officers select routes considering both tactical advantage and

response urgency. 

The combination of fire/rescue, EMS, and police use produces a less

predictable preemption pattern, but there are still some areas of the city

and some signals within the city where the average number of

preemption events in a day is higher than others. Signals located near

hospitals and fire/rescue and EMS stations are preempted more than five

times per day while others are only preempted a few times per week. 

The response time goal for the fire department in St. Paul is 3 minutes

for both fire/rescue and EMS responses. The police department does not

specify a time goal because dispatchers contact officers in the field who

respond from various locations to emergency calls. 

St. Paul is one of only a few jurisdictions in the country that provides

preemption access to every police vehicle, as well as every fire and

emergency vehicle, in the city. Additionally, all emitter-equipped vehicles

from the surrounding communities are allowed to access the St. Paul

system if they are willing to enter a formal agreement with the city. The

main elements of this agreement state that outside emergency

departments will consent to fully train their employees for use of the

preemption equipment, and that they will use the system “as-is,”

waiving any future legal action against the City of St. Paul for any

damages arising from use of the system. Similarly, St. Paul’s emergency

vehicles are permitted full access to the preemption systems of the

neighboring communities, although no formal agreement is required in

most adjacent jurisdictions. 

In St. Paul, the detection thresholds are all set to the maximum range of

approximately 2,300 feet with a 2-second dwell requirement for call

acceptance. The policy was developed in 1998 after the city conducted a

system performance test in an effort to ensure the maximum benefit to

7-9

Emergency Service

Operation

Preemption System

Operations

Site Study Descriptions
the entire user community. The range setting accommodates police

vehicles, which accelerate quickly and often operate at higher speeds

than fire/rescue and EMS vehicles. In addition to the benefit for the

police community, maximum range detection thresholds compensate 

for variation in emitter intensity across St. Paul’s several generations 

of emitter equipment and variation in detection range caused by

differences in emitter installation height. The 2-second dwell

requirement reduces the number of inadvertent preemptions triggered

when preemption equipped vehicles make turns in areas with closely

spaced parallel streets. 

Once in preemption, the signal displays a green ball on all through

lanes for both the concurrent and opposing approaches. Left turn

arrows on signals on the concurrent and opposing approach display a

red arrow to prevent a motorist from making a permissive left turn

across the path of an oncoming EV. Perpendicular approaches are

brought to a red interval for movement in all directions. 

The confirmation light is an important system feature of the St. Paul

EVP system. The lights provide feedback to the EV drivers. The lights

indicate that a request has been received and provide information on

the precedence level of the request in cases when a simultaneous or

near-simultaneous preemption request is made on a perpendicular

approach. The approach that will get the green is provided with a solid

confirmation light while those that will have to yield the right of way

are provided with a flashing confirmation light. Operation of the

confirmation light is part of EV driver training and is integral to the

effort to reduce the potential for crashes.

Figure 7 shows a St. Paul traffic signal in the preemption phase with an

EV crossing right to left through the intersection.

7-10

Figure 7– A St. Paul Signal in the Preemption Phase

St. Paul, Minnesota

EVP System Highlights 

• Installation began

in 1969; oldest

continuously

operating 

deployment of

EVP in the U.S.

• Population of

288,000

• 100 percent of

signals equipped

• Used by fire/

rescue, EMS, and

police vehicles

• 26,000 fire/rescue

and EMS calls 

per year

• 263,000 police

calls per year

Site Study Descriptions
Key questions in any effort to deploy an EVP system are, “What are the

benefits?” and, “What are the costs?” This section provides an overview

of the findings of the cross-cutting study. 

The benefits of EVP range across a variety of public interest issues. The

benefits realized by the three featured sites are summarized in Figure 8.

These benefits include improvements at operational, planning, and

economic levels.

8-1

Cross-Cutting Findings

The Benefits 

of EVP

Figure 8 – Summary of Benefits by Site

Specific examples highlighting the benefits are presented below. 

Fairfax County, Virginia - In nearly all response runs, the system saves

anywhere from a few seconds to a few minutes. Station 11 EV drivers

cited savings of 30-45 seconds at a single intersection such as the one at

U.S. 1 and South Kings Highway (Figure 9). 

Plano, Texas - Plano’s need for EVP stems from the combination of the

layout of its road network and its traffic signal timing plan. Many of

Plano’s streets have center medians and narrow shoulders, so that

vehicles trying to get out of the way of an EV have no place to go.

Therefore, without EVP, it can frequently take two or three cycles to clear

an intersection so that the EV may pass. Many of Plano’s traffic signals

have long cycle lengths of up to 2 or 3 minutes, making it even more

important to install EVP at those intersections to reduce clearance time.

Improved Response

Time

Plano,TX

¥ Reduced fire/ rescue and

EMS response time

¥ Reduced EV crashes

¥ Reduced need for new

fire/rescue and EMS 

stations

¥ Improved insurance 

rating

Fairfax County,VA

¥ Improved response in a 

congested corridor

¥ Reduced intersection 

conflict points

¥ Improved stakeholder communications necessitated

by use of system by transit

vehicles

St. Paul, MN

¥ Reduced fire/ rescue and EMS response time

¥ Reduced EV crashes

¥ Faster police response “Reduced response

time was an

unexpected benefit

that we realized. We

estimate a 10-20

percent reduction. The

system has allowed us

to set and achieve a

response time goal of

90 percent of arrivals

within 6 minutes and

59 seconds even as the

traffic levels have

grown.”

– Bill Peterson

Fire Chief, City of Plano
Plano, Texas - A study conducted by the City of Plano Risk Management

Office indicated that there were 22 EV crashes from 1981 to 1983. Of

these 22 crashes, seven occurred at signalized intersections and may

have been preventable had EVP been in place. Over the 20 years since

the installation of EVP, there have been only four crashes involving

emergency vehicles at intersections. In three of these crashes, the cause

of the crash was failure of the private vehicle involved to stop for the

red signal display correctly generated by the EVP system. The fourth was

caused by EV driver error.

St. Paul, Minnesota - In 1977, St. Paul conducted one of the most

extensive studies of EVP and EV crash rate reduction available.20 The

study documented the rate of EVP deployment across the city’s nearly

300 signals and tracked the number of EV crashes and EV responses over

the same period. Crashes were reduced from the 1967 high of eight EV

crashes to an average of 3.3 EV crashes per year in the latter years of

the study. In the report, the fire chief noted that the improvement in

crash rates occurred despite an increase in the number of alarm

responses and the volume of traffic encountered on the St. Paul

roadways. The fire chief indicated that the decrease in the number of

EV crashes was due to the dramatic reduction in the conflicts EVs are

exposed to at signalized intersections.

Fairfax County, Virginia - An evaluation of traffic flow impact on U.S. 1,

conducted in 2003 by the Virginia Tech Transportation Institute,21 found

that the average duration of a preemption event was 25 seconds and

that delay impacts on side streets were minor. Backups normally cleared

during the first signal cycle following the preemption event. 

8-2

Improved Safety

Traffic Flow 

Impacts of EVP

Figure 9 – A Ladder Truck Without EVP Pushes Through a Queue

at a Red Signal

20 Fire Chief, Department of Fire and Safety Services, St. Paul, Minnesota (1977). Emergency Vehicle

Accident Study (Year 1977).

21 McHale, G. and Collura, J. (2003). “Improving Emergency Vehicle Traffic Signal Priority System

Assessment Methodologies.” Paper presented at the 82nd Annual Meeting of the Transportation

Research Board, Washington, D.C. 2003.

Cross-Cutting Findings

“The system has had

a positive impact on

the service we provide

to the community.”

– Captain Lange,

“C” Shift Captain,

Fire and Rescue Station 11

Fairfax County
Plano, Texas - The degree of impact on traffic flow at a particular

intersection depends on the frequency of calls made on a particular

signal and the level of congestion on the roadway. In Plano, some

signals near hospitals often experience multiple preemption calls

resulting in queues that take several cycles to clear. During peak periods,

it can take 10 to 20 minutes for the traffic flow to return to normal.

However, citizen complaints about the impact are few because of high

public awareness of the purpose of the system. City engineers pointed

out that they get almost immediate cell phone call feedback on

malfunctioning signals but get very few calls that can be attributed to

the impact of a preemption event.

The cost of EVP systems per intersection and per vehicle vary depending

upon the technology selected, the number of units purchased, and the

baseline intersection and vehicle conditions. Intersection cost variables

include the availability of power on the mast arm or signal suspension

cable, the need to run new power and communications cables through

existing conduit, and the availability of suitable detector placement

locations. Vehicle cost variables include whether or not the vehicle was

built with provisions to house the power supply and the emitter and the

requirement to develop special brackets to mount the emitter to the

vehicle.

Equipment costs, by component, reported by the three sites visited are

summarized in Table 6. More information about the costs of emergency

vehicle preemption is available from the ITS Costs Database available at

http://www.itscosts.its.dot.gov.

8-3

The Cost of

EVP

System Component Capital Cost ($K in

2003 dollars)

O&M Cost ($K/yr in

2003 dollars)

Equipment Required per Intersection: 

Signal Preemption Receiver 

w/ optional confirmation light

2 – 3 0.25 – 0.5

Signal Phase Selector 2 – 5 No specific maintenance

required

Equipment Required per Vehicle:

Signal Preemption Emitter

Note: Initial cost includes a power

supply and the emitter (high end of

cost range) while maintenance costs

primarily entail optical emitter replacement (low end of cost range)

0.7 – 2.1 Remove and replace 

the optical emitter upon

failure

Table 6 – Typical Costs of EVP Equipment

“The vehicle queues

on side-street

approaches became

slightly longer but

would typically clear

during the first green

phase following the

preemption event.”

– Doug Hansen

Senior Transportation

Planner, Fairfax County

“The public is aware

of the preemption

system and tolerates

the inconvenience as

part and parcel to the

high quality of

emergency services

they have grown to

expect.”

– Lloyd Neal

Transportation Engineering

Manager, City of Plano

Cross-Cutting Findings
Fairfax County, Virginia - In Fairfax County, the county is responsible for

the cost of equipment purchase and installation on VDOT owned signal

systems. Because the Fairfax County deployment involved a retrofit of

existing signals, the costs per intersection varied due to a range of signal

suspension methods employed along the corridor. Each intersection was

surveyed to determine the special design considerations and the impact

on the project budget and the deployment schedule. Across seven

intersections in the operational test section, the average cost was

between $4,000 and $6,000 per intersection (equipping two arterial

approaches only). 

Fairfax County is responsible for maintenance of the system. The county

has employed a maintenance contractor that bills the county directly. As

of 2004, experience from the field operational test was being used to

develop a county budget line item that will cover the 50 existing or

near-term planned EVP intersections. County officials estimated these

annual EVP maintenance costs to be between $250 and $500 per year. 

Plano, Texas - Plano, Texas does not separate out costs of the EVP

system because it is fully integrated into traffic signal operations.

However, the traffic engineering department estimates that the cost to

install the preemption detection on a new signal at all four approaches

is between $5,000 and $8,000 of the $105,000 (or higher) total cost of

the signal design, installation, and integration. Differences in cost are

dependent upon such factors as the site requirements for power and

mast arm installation.

Because Plano owns and operates the EVP systems and the signal

systems, the city does not differentiate signal maintenance costs and

preemption maintenance costs. EVP maintenance costs are part of the

overall signal system maintenance budget. Plano reports that most

system failures are traceable to construction and damage to power and

signal communications conduits in the vicinity of the intersection. 

St. Paul, Minnesota - In the City of St. Paul, the cost of preemption

equipment is integral to the cost of new signals. The city estimates the

cost of equipping a new traffic signal with preemption capability is

approximately $6,000 to $8,000 at all four approaches, provided that

the necessary conduits, wiring, and power sources are available. 

St. Paul performs regular preventive maintenance on EVP detectors,

including lens cleaning and removal of tree overgrowth that prevents

the equipment from receiving a preemption call. City maintenance staff

trim nearby tree branches and clean the receiver lenses every two years.

St. Paul does not differentiate signal maintenance costs and preemption

maintenance costs. Both preventive and responsive EVP maintenance

are included in the Department of Public Works annual budget. 

8-4

Cross-Cutting Findings

“For a site, the

structure, and the

apparatus, the cost is

about $3 million (2004

dollars); and the

continuous operations

and maintenance costs

are about $2.5 million

per year for each

station.”

– Bill Peterson

Fire Chief, City of Plano
Plano, Texas - As part of its 20-year growth plan developed in the mid1980s, Plano estimated that one fire/rescue and EMS stations would be

required for every 5.6 square miles to provide the desired level of

service. As the city grew, the response time benefit of EVP has been

incorporated into the geographical information systems (GIS)-based

planning models the city uses to evaluate fire/rescue and emergency

medical service expansion needs. As a result, the city is now serving 7.5

square miles per station instead of the anticipated 5.6 square miles. The

benefit to the city is that it is currently operating 10 stations compared

with the 13 that had been forecast resulting in a capital cost savings for

the city of approximately $9 million and an annual operating cost

savings of approximately $7.5 million. 

8-5

Potential Cost Savings

Cross-Cutting Findings

This section summarizes the lessons learned reported by the three sites

so that those considering EVP can minimize deployment delays and

maximize system performance. The lessons presented were common

across the three sites. They are presented in terms of institutional issues,

public acceptance, EV driver training, system installation, and system

maintenance. 

• Involve all appropriate stakeholders in a collaborative manner

throughout the planning, deployment, and operations phases. EVP

systems have the capacity to impact a number of city, county, and

state agencies. Successful EVP projects will involve a wide-ranging

stakeholder group that should consider a memorandum of

understanding outlining the short and long-term roles of each

member. 

• Identify a champion and define the role to maintain a consistent

advocacy message. To prevent the effort from stalling, it may prove

beneficial for the stakeholder group to designate a specific

champion for the system. In a typical EVP deployment, the initial

champions come from the fire/rescue and EMS community. Over

time, however, local officials become advocates, or maybe even

champions, as local governments decide whether or not to support

the system financially. 

• Launch a public awareness campaign highlighting the public safety

benefits of preemption at these and other signals. An important

step in achieving public acceptance is to inform the community of

the purpose and benefits of EVP. Extra outreach may be needed in

areas surrounding intersections near hospitals or fire/rescue and EMS

stations as these intersections experience more preemption calls than

other intersections, often resulting in more delays around these

facilities. 

• Document standard operating procedures and driving techniques

and review them in regular training sessions. Driver training is key

to minimizing EV crashes. EV drivers at each site visited stated that

the main lesson learned was not to over-rely on the system and to

proceed as if preemption would not be granted. 

• Bench test the equipment and software in the shop with the same

equipment that is found in the field. Bench testing prevents

potential problems in the field. VDOT found that traffic signal

controller software required an upgrade to allow dual use of the

technology for both EVP and transit signal priority. Prior to the

upgrade, testing revealed that transit priority requests would be

granted the same level of precedence as EVP requests, whereas

VDOT wanted EVP requests to take precedence. 

9-1

Lessons Learned

Overcoming

Institutional

Issues

Public

Acceptance

EV Driver

Training

System

Installation
• Wire the vehicle emitter into the EV parking brake or transmission

lever to turn the emitter off while the EV is stopped. When EVs

stop in the vicinity of an intersection, a continuously running

emitter will hold the signal in the preemption phase indefinitely,

causing significant traffic problems. Systems with factory-installed

emitters are usually delivered with a power interrupt tied to the

transmission shift lever that disables the emitter when the vehicle is

in “park.” Both the Fairfax County and Plano apparatus shops had

to develop custom power interrupt solutions for vehicles with

locally-installed emitters. 

• Maintain an open line of communication among stakeholders during

the acceptance testing period to avoid poor system performance

and perhaps avert a dangerous situation. Resolving system

performance issues requires cooperation and communication

between EV drivers and EVP maintenance technicians. Certain

signalized intersections may pose problems in terms of emitterdetector line-of-sight reducing detection ranges. Finding the right

solution requires detailed problem descriptions. 

The key to maintenance success is identification of a single agency to be

responsible for scheduling, coordinating, and funding system

maintenance. This agency may be the city traffic engineering

department or the fire/rescue and EMS department. If the fire/rescue

and EMS department contracts out for maintenance services, a

memorandum of agreement should be drafted with the agency that

controls signal cabinet access to document service call precedence,

cabinet access procedures, service log requirements, and any other

necessary site-specific coordination issues.

• Develop a maintenance problem-reporting channel. The purpose is

to enable the users of the system to easily report problems so that

problems can be screened for response priority and the potential for

dangerous situations is minimized. Figure 10 shows a VDOT

technician in Fairfax County, Virginia overseeing contract

maintenance on the EVP system.

• Ensure a standard fault isolation protocol is in place. Having a

documented system for trouble-shooting will reduce the repeat/recur

rate as well as the maintenance call false alarm rate.

• Perform concurrent maintenance. In addition to serving maintenance

requests, there may be benefit in performing preventive

maintenance in conjunction with regular traffic signal equipment

maintenance. A task such as detector lens condition inspection can

be done in conjunction with signal lamp replacement. St. Paul

reports that this practice has helped reduce service calls.

9-2

System

Maintenance

“In nearly every

situation, some type of

adjustment was

needed to clear the

way for using

preemption and

priority...it was not a

purely ‘plug and play’

application.”

– Bob Sheehan

Signal Systems Manager,

VDOT

Lessons Learned
9-3

Figure 10 – A Technician Oversees Contract EVP Maintenance

“It’s not easy to pin

down ‘who’s doing

what’ when you have

multiple groups

entering the controller

cabinets...there are

far-reaching liability

implications should

the system

malfunction due to

human error.

It comes back to

communication. As

long as we know

what’s going on in the

field with the

equipment, we can

satisfy everyone’s

objectives.”

– Bob Sheehan

Signal Systems Manager,

VDOT

Lessons Learned

10-1

Communities across the country are striving to provide the highest

possible levels of fire/rescue, EMS, and police services. These efforts have

gained new meaning as towns, cities, counties, states, and regions

improve emergency response in support of homeland security and

disaster preparedness. 

EVP is one item in the toolkit that improves the responsiveness of public

safety services. EVP has the potential to:

• Reduce the potential for an EV to be in a crash en-route to the

emergency scene or to the hospital, reducing liability and keeping

EVs in service.

• Help to get fire/rescue and EMS apparatus to the scene quickly and

to put law enforcement in a tactically advantageous position.

• Reduce emergency medical service response time and patient

transport time, saving critical minutes and increasing the chance of

survival for the cardiac arrest or trauma patient.

• Be a cost-effective alternative to building new stations by increasing

the effective service radius of current facilities.

• Be a catalyst for developing broader cooperation between

jurisdictions as they develop or further mutual aid agreements as

part of regional emergency response plans.

• Provide the foundation for transit signal priority when deployed on

key transit corridors.

When EVP is implemented well, the negative impacts on traffic flow are

not significant and public acceptance of the system is high. For example,

it is often the case in jurisdictions with EVP that:

• Most signals are rarely preempted and those that are near EV points

of origin and destination experience delays that are in line with

those experienced in normal peak hour conditions.

• Signal timing plans are generally reestablished in one to three cycles

after an EV preemption event.

• Public awareness grows quickly and complaints about the system

decrease.

Communities using EVP have experienced significant benefits with

minimal negative impacts. Proactive collaboration among informed

stakeholders are key to successful deployment of EVP that helps put the

“first” in “first response.” 

Conclusion

Federal Highway Administration (2003). Manual on Uniform Traffic

Control Devices (MUTCD) 2003 Edition, Part 4: Highway Traffic Signals.

http://www.mutcd.fhwa.dot.gov.

The MUTCD 2003 Edition, includes explicit definitions of preemption

and priority at traffic signals. These definitions, combined with

instructions for phase transition, reduce some of the issues of

concern in EVP deployments by providing the guidance that traffic

engineers require to ensure safety and efficiency in operations.

Minnesota Department of Transportation (2005). Minnesota Manual on

Uniform Traffic Control Devices (MN MUTCD) Part 4: Highway Traffic

Signals. http://www.dot.state.mn.us/trafficeng/otepubl/mutcd.

This section of the Minnesota Department of Transportation’s

MUTCD provides guidance on the installation and operation of EVP

systems. The document codifies the lessons learned over 30 years of

experience with EVP in Minnesota. The guidance includes detailed

instructions for the use of EVP, the design of EVP preemption phases,

and the use of confirmation lights. The manual also includes

requirements for new signal installation and the inclusion of

provisions for installation of EVP. 

Arizona Department of Transportation (2002). ADOT Traffic Engineering

Policies, Guidelines, and Procedures; Section 600 - Traffic Signals.

http://www.azdot.gov/highways/traffic/pgp.asp.

This section of the Arizona Department of Transportation’s (Arizona

DOT’s) traffic engineering policy document outlines responsibilities

for the key stakeholders in EVP deployments. The document lays out

the Arizona DOT policy on who owns, operates, and maintains EVP

equipment for jurisdictions in which Arizona DOT owns the traffic

signal system and for jurisdictions in which the jurisdiction itself

owns and operates the traffic signal system. 

Collura, John, Rakha, H. and Gifford, J. (2003). Guidelines for the

Planning and Deployment of Emergency Vehicle Preemption and Transit

Priority Strategies.

http://signalsystems.tamu.edu/documents/Jan2004AnnualMeeting/

SundayWorkshop/GuidelinesEVPandTP_Draft1.0.pdf. 

This document provides guidelines on the planning and deployment

of both EVP and transit signal priority, including integration of the

two. Aspects of the planning process covered in the guidelines

include examining institutional issues, conducting an assessment of

local needs, determining system objectives and requirements,

estimating traffic flow and safety benefits, estimating economic

impacts, and obtaining financing. Deployment considerations

covered in the guidelines include procurement, pre-installation site

surveys, installation, and evaluation.

11-1

Resources

Federal and

State Guidelines

on EVP

Implementation

Responsibilities

in EVP

Deployment,

Operations, and

Maintenance

Information on

Organizing,

Planning,

Deploying, and

Operating EVP

Bullock, D., Morales, J., and Sanderson, B. (1999). Evaluation of

Emergency Vehicle Signal Preemption on the Route 7, Virginia, Corridor.

Washington, D.C.

Gifford, J., Pelletiere, D., and Collura, J. (2001). “Stakeholder

Requirements for Traffic Signal Preemption and Priority in the

Washington, D.C. Region”. Transportation Research Record. No. 1748.

pp. 1-7.

McHale, G. and Collura, J. (2003). “Improving Emergency Vehicle Traffic

Signal Priority System Assessment Methodologies”. Paper presented at

the 82nd Annual Meeting of the Transportation Research Board.

Washington, D.C. 2003.

Nelson, E. and Bullock, D. (2000). “Impact Evaluation of Emergency

Vehicle Preemption on Signalized Corridor Operation”. Paper presented

at the 79th Annual Transportation Research Board Meeting.

Washington, D.C. 2000.

Obenberger, J. and Collura, J. (2001).”Transition Strategies to Exit

Preemption Control: State-of-the-Practice Assessment”. Transportation

Research Record. No 1748.

Skabardonis, A. (2000).”Control Strategies For Transit Priority”. Paper

presented at the 79th Annual Transportation Research Board Meeting.

Washington, D.C. 2000.

12-1

Additional Resources

Public Safety Coordinator

Linda Dodge

ITS Joint Program Office

Federal Highway Administration

Room 3416, HOIT-1

400 7th Street SW

Washington, DC 20590

Phone 202-366-8034

Facsimile 202-493-2027

linda.dodge@fhwa.dot.gov

Emergency Medical Services Division

National Highway Traffic Safety Administration

Room 5125

400 7th Street SW

Washington, DC 20590

Phone 202-366-5440

Facsimile 202-366-7721
Federal Highway Administration Resource Center Locations

Baltimore, MD

10 S. Howard Street

Suite 4000

Baltimore, MD 21201

Phone 410-962-0093

Facsimile 410-962-3419

Atlanta, GA

61 Forsyth Street, SW

Suite 17T26

Atlanta, GA 30303

Phone 404-562-3570

Facsimile 404-562-3700

Olympia Fields, IL

19900 Governors Drive

Suite 301

Olympia Fields, IL 60461

Phone 708-283-3500

Facsimile 708-283-3501

San Francisco, CA

201 Mission Street

Suite 2100

San Francisco, CA 94105

Phone 415-744-3102

Facsimile 415-744-2620

National Highway Traffic Safety Administration Regional Offices

New England Region

Volpe National Transportation Systems Center

55 Broadway - Kendall Square - Code 903

Cambridge, MA 02142

Phone (617) 494-3427

Facsimile (617) 494-3646

region1@nhtsa.dot.gov

Eastern Region

222 Mamaroneck Avenue, Suite 204

White Plains, NY 10605

Phone (914) 682-6162

Facsimile (914) 682-6239

region2@nhtsa.dot.gov

Mid-Atlantic Region

10 S. Howard Street, Suite 6700

Baltimore, MD 21201

Phone (410) 962-0090

Facsimile (410) 962-2770

region3@nhtsa.dot.gov

Southeast Region

Atlanta Federal Center

61 Forsyth Street, SW

Phone (404) 562-3739

Facsimile (404) 562-3763

region4@nhtsa.dot.gov

Great Lakes Region

19900 Governors Drive, Suite 201

Olympia Fields, IL 60461

Phone (708) 503-8822

Facsimile (708) 503-8991

region5@nhtsa.dot.gov

South Central Region

819 Taylor Street, Room 8A38

Fort Worth, TX 76102

Phone (817) 978-3653

Facsimile (817) 978-8339

region6@nhtsa.dot.gov

Central Region

901 Locust Street, Room 466

Kansas City, MO 64106

Phone (816) 329-3900

Facsimile (816) 329-3910

region7@nhtsa.dot.gov

Rocky Mountain Region

12300 West Dakota Avenue, Suite 140

Lakewood, CO 80228

Phone (720) 963-3100

Facsimile (720) 963-3124

region8@nhtsa.dot.gov

Western Region

201 Mission Street, Suite 2230

San Francisco, CA 94105

Phone (415) 744-3089

Facsimile (415) 744-2532

region9@nhtsa.dot.gov

Northwest Region

3140 Jackson Federal Building

915 Second Avenue

Seattle, WA 98174

Phone (206) 220-7640

Facsimile (206) 220-7651

region10@nhtsa.dot.gov
THIS DOCUMENT IS ONE IN A SERIES OF PRODUCTS THAT ADDRESS

ITS ISSUES PERTINENT TO A VARIETY OF AUDIENCES

Elected and Appointed Officials • Senior Decision Makers

Transportation Managers • Technical Experts

Representing:

States • Cities • Counties • Motor Carriers 

Licensing and Registration Service Bureaus • Law Enforcement 

Public Utilities/Commercial Vehicle Enforcement 

Additional Transportation Stakeholders

ITS Topics Addressed in This Series:

• Commercial Vehicle Operations

• Emergency Services

• Enabling Technologies

• Emissions Management

• Freeway and Arterial 

Management

• Planning and Integration

• Real-Time Traveler Information

• Transit, Toll, and Rail Management

• Weather Information for Travelers

and Maintenance

• Work Zones

For a current listing of available documents, please visit our website at:

http://www.its.dot.gov

Benefits Brochures quote how ITS

technologies have benefited specific areas.

Cross-Cutting Studies present current

data from related ITS applications.

Case Studies provide in-depth coverage

of ITS applications in specific projects.

Products Available in This Series

Technical Reports include results from

various Field Operation Tests.

Implementation Guides assist

project staff in the technical details of

implementing ITS.
FHWA-JPO-05-010 EDL# 14097

INTELLIGENT TRANSPORTATION SYSTEMS

U.S. Department of Transportation 

400 7th Street SW

Washington, DC 20590

‘‘It’s like a day and night 

comparison on a call when 

you’re on a truck with, or 

without, the preemption system...

It definitely gets you where 

you’re going faster.”

—Captain Lange, ‘‘C” Shift Captain, 

Fire and Rescue Station II, Fairfax County

National Highway Traffic Safety Administration

Emergency Medical Services Division

Room 5125, NTI-123

Phone: 202-366-5440

Facsimile: 202-366-7721

Federal Highway Administration

ITS Joint Program Office

Room 3416, HOIT-01

Phone: 866-367-7487

Facsimile: 202-493-2027