TRL GUIDEBOOK a

TECHNOLOGY

READINESS

LEVEL

GUIDEBOOK

EXPLORATORY ADVANCED RESEARCH
b TRL GUIDEBOOK 

Notice

This document is disseminated under the sponsorship of the U.S. Department of Transportation in the 

interest of information exchange. The U.S. Government assumes no liability for the use of the information 

contained in this document.

The U.S. Government does not endorse products or manufacturers. Trademarks or manufacturers’ names 

appear in this report only because they are considered essential to the objective of the document.

Quality Assurance Statement

The Federal Highway Administration (FHWA) provides high-quality information to serve Government, 

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Cover photos

Main: Photo of a moderately full multilane highway at sunset with cars and trucks

sharing the road, traveling in opposite directions. © 2016: Tomas Sereda.

Center: Image showing an aerial photograph of traffic traveling along the

various arms of a city viaduct bridge road landscape. © 2017: 123 Artist Images.

Foreword photo

Photo of mechanical engineers working in a turbo charger automotive research laboratory. 

© 2015: Monty Rakusen.
TRL GUIDEBOOK i

FOREWORD

The mission of the Department of 

Transportation is to serve the United 

States by ensuring a fast, safe, 

efficient, accessible, and convenient 

transportation system. Ongoing 

research activities offer an opportunity 

to explore methods of making our 

transportation system more robust in 

all of these ways. From researching 

novel modes of transportation to 

developing advances in agent-based 

modeling of traveler behavior, research 

is at the core of making our system one 

that enhances the quality of life of the 

American people. 

The Federal Highway Administration 

(FHWA) Exploratory Advanced 

Research (EAR) Program focuses on 

high-risk, high-reward research that 

bridges the gap between basic and 

applied research. It also supports 

the development of transformative 

research tools that can accelerate 

development of solutions for highwayrelated challenges. The value of this 

type of research lies in how researchers 

in Government, academia, and industry 

use the results. For EAR Programsponsored projects that reach or 

exceed their anticipated results or 

develop other advances that have 

immediate or near-term value, the EAR 

Program is committed to providing 

the support necessary to apply those 

results toward advancing roadwayrelated tools and technologies.

In fulfilling its mission, the EAR 

Program identified the need for a 

system to describe the maturity of 

highway research products. Numerous 

mechanisms exist for sharing research 

results, including technical reports, 

fact sheets, and demonstrations, but 

capturing the core of the research 

project while offering tangible next 

steps is a more difficult undertaking. 

The EAR Program uses Technology 

Readiness Level (TRL) Assessments 

along with other tools to help identify 

which research products to emphasize 

for transition and which audiences 

would be interested in the results.

The lessons presented in this 

Guidebook will help those working in 

transportation research to conduct 

an evaluation that will likely rank the 

maturity of a technology and describe 

the followup steps for advancing their 

efforts. 
Technical Report

Documentation Page

Form DOT F 1700.7 (8-72) Reproduction of completed page authorized.

1. Report No.

FHWA-HRT-17-047 2. Government Accession No. 3. Recipient’s Catalog No.

4. Title and Subtitle

Technology Readiness Level Guidebook

5. Report Date

September 2017

7. Author(s)

Nate Deshmukh Towery, Elizabeth Machek, Anthony Thomas 6. Performing Organization Code

9. Performing Organization Name and Address

U.S. Department of Transportation 

Volpe Center

55 Broadway

Cambridge, MA 02142

8. Performing Organization Report No.

10. Work Unit No. (TRAIS)

11. Contract or Grant No.

Contract DTFH61-14-V-00025

12. Sponsoring Agency Name and Address

Exploratory Advanced Research Program

Federal Highway Administration

6300 Georgetown Pike

McLean, VA 22101-2296

13. Type of Report and Period Covered

Final Report

February 3, 2016 – October 31, 2016

14. Sponsoring Agency Code

15. Supplementary Notes

FHWA‘s Contracting Officer’s Technical Representative: Zachary Ellis (HRTM-30)

Technical Contact: David Kuehn (HRTM-30)

16. Abstract

This guidebook provides the necessary information for conducting a Technology Readiness Level (TRL) Assessment. TRL 

Assessments are a tool for determining the maturity of technologies and identifying next steps in the research process. 

This guidebook offers background on the TRL Scale, walks through every aspect of preparing for and conducting a TRL 

Assessment, and provides helpful tools and tips throughout. TRL Assessments are flexible evaluation tools and can be 

used in a variety of settings to fit the needs of the agency conducting them. Having a simple mechanism to determine and 

communicate technology maturity improves research outcomes and program management.

17. Subject Terms

Technology Readiness Levels, TRLs, Portfolio Assessment, 

Research Management, Evaluation, TRL Scale, Advanced 

Research, Technology Adoption

18. Distribution Statement

No restrictions. This document is available to the public 

through the National Technical Information Service, 

Springfield, VA 22161. 

http://www.ntis.gov

19. Security Classif. (of this 

report)

Unclassified

20. Security Classif. (of this 

page)

Unclassified

21. No. of Pages

52 22. Price

ii TRL GUIDEBOOK
Introduction 1

1. What is a TRL? 3

 Why Use the TRL Scale? 3

 What Not to Do with the TRL Scale? 3

 Understanding the TRL Scale 4

 The ETC Examples 5

2. Preparing for the TRL Assessment 11

 Selecting Panelists—The Experts and User Community 11

 Establishing Goals—“Why are we assessing this technology?” 12

 Formalizing Timing and Location—The Nuts and Bolts 12

 Creating Materials—Getting to the Starting Line 13

3. Conducting a Successful TRL Assessment 15

4. Using the Results of TRL Assessments 17

Conclusion 19

Appendices

Appendix A. Technology Framing Documents 21

Appendix B. Principal Investigator Questionnaire 23

Appendix C. TRL Assessment Report Example 27

Appendix D. Frequently Asked Questions 31

Appendix E. Example Projects and Associated Technology Readiness Levels 33

Appendix F. TRL Scale 37

Appendix G. Additional Resources on the TRL Scale and the Use of TRLs For Assessment 39

Glossary of Terms and Acronyms 41

References 43

TRL GUIDEBOOK iii

Table of Contents
List of Figures

Figure 1. TRL Assessment process 1

Figure 2. The four categories of the TRL Scale 4

Figure 3. IIllustration. Automatic toll charging system, U.S. Patent 3602881 6

Figure 4. Photo. A fully operational ETC at George Washington Bridge in New Jersey 9

Figure 5. Major components of a TRL Assessment 11

Figure 6. Chart. TRLs across Federal funders in transportation 19

Figure 7. Illustration. Sample TRL worksheet 29

List of Tables

Table 1. Appropriate and inappropriate uses of the TRL Scale 4

Table 2. Descriptions and requirements of TRLs 1, 2, and 3 5

Table 3. Descriptions and requirements of TRLs 4 and 5 6

Table 4. Descriptions and requirements of TRLs 6, 7, and 8 8

Table 5. Description and requirements of TRL 9 9

Table 6. Example agenda for TRL Assessment panel meeting 15

Table 7. PI Questionnaire 23

Table 8. Example 1. Innovative bridge design and rapid renewal: design tool kit 33

Table 9. Example 2. Increased understanding of driver visibility requirements 34

Table 10. Example 3. Anonymous traffic probes for travel time and origin-destination

using Bluetooth IDs

35

Table 11. TRL Scale: Descriptions and requirements 37

List of Figures and Tables

iv TRL GUIDEBOOK
Researchers use evaluation as a key

 component of the research process. 

Funding agencies use evaluation tools to 

rank the maturity level of a technology within 

the context of the research process. Agency 

researchers examine how a technology was 

developed and how that technology functions 

within its defined operating environment at 

the time of the examination. They include 

this information in their evaluation before 

ranking the maturity level. In some cases, the 

researchers evaluate a technology to determine 

its readiness for inception into a technology 

system (deployment). In other cases, they 

evaluate it to determine if funding should 

continue to support the research. 

A Technology Readiness Level (TRL) Assessment 

is a tool for determining the maturity of a 

technology and provides a foundation for 

identifying next steps in the research process. 

Researchers use TRL Assessments as a 

means to understand a research project’s 

technological maturity, but the assessments 

have their limitations. TRL Assessments 

can help improve communication, research 

outcomes, and contract management, but they 

do not address risk, cost, or the feasibility of 

deployment. Therefore, examiners should use 

TRL Assessments alongside other evaluation 

techniques to obtain a complete picture of a 

research project’s maturity.

This Guidebook provides the necessary 

information for conducting a TRL Assessment. 

It offers background on the TRL Scale (shown 

in appendix F),1

 walks through every aspect 

of preparing for and conducting the TRL 

Assessment, and provides many helpful 

tools and tips throughout. The Guidebook 

begins with an explanation of the TRL Scale, 

because it provides the foundation for the TRL 

Assessment. Researchers follow a specific 

process for conducting the TRL Assessment,

as shown in figure 1.

Introduction

What is

a TRL?

Conducting

a Successful

TRL 

Assessment

Working 

with TRL 

Assessment

Results

Preparing 

for the TRL 

Assessment

Figure 1. TRL Assessment process.

1

All references within this document to the “TRL Scale” refer to a modified TRL Scale developed by the Volpe Center for Highway 

Transportation R&T on behalf of FHWA.

This Guidebook is broken into the four sections below:

TRL GUIDEBOOK 1
2 TRL GUIDEBOOK
T

he TRLs are formal metrics that support 

assessments of a particular technology 

and provide the ability to consistently 

compare levels of maturity between different 

types of technologies. The TRL Scale uses a 

set of questions designed to measure progress 

of a technology toward maturity. The National 

Aeronautics and Space Administration (NASA) 

originally developed the concept of TRLs. Later, 

other Federal agencies, notably the U.S. 

Department of Defense, adapted the TRL 

concept. 

The TRL Scale assesses the maturity of a 

technology in terms of certain characteristics, 

as measured by successful tests. The scale 

considers two aspects of the completed tests:

• How complete was the technology when it 

was tested? (Was it a paper-and-pen concept,

a system of equations, a component, a 

subsystem, or the complete system?)

• How representative was the test environment?

 – Was it a computer simulation, a controlled 

laboratory experiment, a demonstration at 

a proving ground, or a real-world test?

 – How similar was the tester to the ultimate 

technology user? Was the tester the 

developer of the technology, another 

expert in the field, or a user with no 

more specific knowledge than the typical 

technology user?

Why Use the TRL Scale? 

The TRL Scale focuses on completed tests 

and a typical testing progression toward 

technology adoption. Assessment panel 

members can use the scale to identify 

immediate next steps for a research or 

technology development project. Technical 

experts and program managers can use the TRL

Scale as a guide to structure discussions about

the state of development (or maturity) of a

single technology. All parties to the assessment

can reach a shared understanding of the 

technical state of the project by considering 

and debating the questions that comprise the 

TRL Scale. During its discussion, the panel can 

uncover technical gaps and questions that point

toward next steps in the technology’s 

development. The discussion also helps to 

identify remaining steps and approximate the

level and duration of effort needed to move a

technology from its current state into deployment.

What Not to Do with the TRL Scale?

The TRL Scale focuses solely on the tests 

completed in the development of a technology, 

so the range of appropriate uses for it as an 

assessment tool is fairly narrow. The TRL 

Scale does not identify risks or challenges in 

technology development, such as:

• The difficulty of advancing the technology to 

the next level of readiness.

• The potential impact or benefit of the 

technology.

• The market for a technology.

Because of this limitation, assessors should 

include these indicators beyond the TRL when 

evaluating a project. The table below provides 

an explanation of the appropriate

and inappropriate uses of the TRL Scale. 

Researchers must decide if the TRL Scale 

is an appropriate assessment tool for each 

technology product, as shown in table 1.

1. What is a TRL?

TRL GUIDEBOOK 3
.

Understanding the TRL Scale

TRLs range from Level 1 (basic research) to 

Level 9 (implementation). To achieve a specific 

TRL, the technology must meet all of the 

requirements within that level and prior levels. 

Each level indicates a different measure of 

maturity and contains different requirements to 

determine the level of technical maturity. 

The remainder of this section walks the reader 

through a description and requirements for 

each TRL and uses a real-world transportation 

technology example—Electronic Toll Collection 

(ETC)—to highlight the research maturity 

process of a set of technologies toward 

deployment. The TRL Scale has four categories: 

basic research, applied research, development, 

and implementation (figure 2).

Table 1. Appropriate and inappropriate uses of the TRL Scale.

Appropriate Uses Inappropriate Uses

Identify technical gaps to be filled to 

advance the technology.

Evaluate investment required to advance the technology.

Estimate the technical impact of the technology.

Perform a rough portfolio analysis in 

terms of technology maturity.

Analyze the market for the technology.

Use as a single indicator for whether projects should continue.

Serve as a “shorthand” when discussing 

the project status, internally and 

externally.

Use to evaluate projects designed to facilitate implementation 

of an existing technology.

Use to evaluate projects that include multiple subprojects with 

different user communities or underlying technologies.

Basic Research

1 Basic principles 

and research.

2 Application 

formulated.

3 Proof of concept.

Applied Research

4 Components 

validated in 

a laboratory 

environment.

5 Integrated 

components 

demonstrated 

in a laboratory 

environment.

Development Implementation

6 Prototype 

demonstrated 

in relevant 

environment.

7 Prototype 

demonstrated 

in operational 

environment.

8 Technology proven 

in operational 

environment.

9 Technology 

refined and 

adopted.

Figure 2. The four categories of the TRL Scale.

1. What is a TRL? cont.

4 TRL GUIDEBOOK
The TRL Scale begins with basic research, 

as shown in table 2. For the case of ETC, the 

basic research focused on radio transponders. 

The precursor to ETC was radio-frequency 

identification (RFID) technology. Researchers 

developed radio transponders leading up to 

and during WWII. Military personnel used 

them to identify whether planes were Allied or 

enemy in an application called “identification, 

friend, or foe.” 

TRL Description Requirements

1 Basic principles

and research

• Do basic scientific principles support the concept?

• Has the technology development methodology or 

approach been developed?

2 Application formulated

• Are potential system applications identified?

• Are system components and the user interface at 

least partly described?

• Do preliminary analyses or experiments confirm that 

the application might meet the user need?

3 Proof of concept

• Are system performance metrics established? 

• Is system feasibility fully established?

• Do experiments or modeling and simulation validate 

performance predictions of system capability?

• Does the technology address a need or introduce an 

innovation in the field of transportation?

The ETC Examples

Basic Research

Table 2. Descriptions and requirements of TRLs 1, 2, and 3.

To illustrate the requirements for each TRL, a set of example projects and their related TRLs 

are provided at the end of this guidebook. 

TRL GUIDEBOOK 5

1. What is a TRL? cont.
Following WWII, patent applications in the 

1950s and 60s identified ETC as a potential 

application for radio transponder technology, 

and economist William Vickrey proposed 

a hypothetical ETC system in The American 

Economic Review in 1963 (Vickrey, 1963). 

Still, there was no proof of concept until the 

early 1970s, when researcher Mario Cardullo 

developed a passive radio transponder with 

memory and demonstrated the concept to 

potential ETC users (Cardullo, 2003). The first 

three levels of the TRL Scale describe this kind 

of basic research. TRLs four and five capture 

the transition into applied research. Once TRL 5 

is complete, research enters the development 

phase. Implementation marks a technology 

reaching TRL 9. The TRL Scale continues with 

applied research, as shown in table 3. A patent 

for automated toll charging (figure 3) was 

awarded in 1971 (United States Patent and 

Trademark Office, 1971), accessed through

https://www.google.com/patents/US3602881.

Applied Research

Table 3. Descriptions and requirements of TRLs 4 and 5.

Figure 3. Illustration. Automatic toll charging system, U.S. Patent 3602881.

Source: United States Patent and Trademark Office, www.uspto.gov.

TRL Description Requirements

4 Components validated in 

laboratory environment

• Are end-user requirements documented?

• Does a plausible draft integration plan exist, and is component 

compatibility demonstrated?

• Were individual components successfully tested in a laboratory 

environment (a fully controlled test environment where a 

limited number of critical functions are tested)?

5

Integrated components 

demonstrated in a 

laboratory environment

• Are external and internal system interfaces documented?

• Are target and minimum operational requirements developed?

• Is component integration demonstrated in a laboratory 

environment (i.e., fully controlled setting)?

1. What is a TRL? cont.

6 TRL GUIDEBOOK
TRLs four and five capture the transition 

to applied research. In the early 1970s, 

researchers at the Los Alamos National 

Laboratory began to develop and validate 

RFID tags for use in tracking systems for 

the U.S. Department of Energy—which was 

researching how to track nuclear materials—

and the U.S. Department of Agriculture, which 

had the objective of tracking livestock (Violino 

& Roberti, 2005). 

Throughout the 1970s and 1980s, laboratory 

research continued on RFID systems. As 

the technology matured and moved into 

development activities, Federal research led 

to the spinoff of private companies, such as 

Identronix and Amtech.

TRL GUIDEBOOK 7

The TRL Scale focuses on completed tests and 

a typical testing progression toward technology 

adoption. Assessment panel members can use 

the scale to identify immediate next steps for 

a research or technology development project. 

Technical experts and program managers can use 

the TRL Scale as a guide to structure discussions 

about the state of development (or maturity)

of a single technology.

“

“

1. What is a TRL? cont.
Development

Table 4. Descriptions and requirements of TRLs 6, 7, and 8.

TRL Description Requirements

6

Prototype 

demonstrated 

in relevant 

environment

• Is the operational environment (i.e., user community, physical environment, 

and input data characteristics, as appropriate) fully known?

• Was the prototype tested in a realistic and relevant environment outside 

the laboratory?

• Does the prototype satisfy all operational requirements when confronted 

with realistic problems?

7

Prototype 

demonstrated 

in operational 

environment

• Are available components representative of production components?

• Is the fully integrated prototype demonstrated in an operational 

environment (i.e., real-world conditions, including the user community)?

• Are all interfaces tested individually under stressed and anomalous conditions?

8

Technology 

proven in 

operational 

environment

• Are all system components form-, fit-, and function-compatible with each 

other and with the operational environment?

• Is the technology proven in an operational environment (i.e., meets target 

performance measures)?

• Was a rigorous test and evaluation process completed successfully?

• Does the technology meet its stated purpose and functionality as designed?

The TRL Scale is used to measure the 

development of a technology product,

as shown in table 4. After TRL 5 is reached, 

research enters the development phase. 

In the 1980s, researchers tested early ETC 

prototypes on closed courses and public 

roads (TRB, 2016). As tests continued, 

the researchers replaced small temporary 

installations with larger deployments that 

had more readers and transponders. Limited 

vehicles (test, government, or commercial 

vehicles) used the systems during initial pilot 

phases. The public started using them after 

research proved them safe and effective.

1. What is a TRL? cont.

8 TRL GUIDEBOOK
Implementation marks a technology reaching 

TRL 9. Researchers can use TRL 9 to measure 

a product’s implementation (table 5). For the 

case of ETC, early adopters of fully deployed 

systems included Texas in 1989 (North Texas 

Tollway Authority, n.d.) and Oklahoma in 

1991 (U.S. Department of Transportation, 

2016). As the years passed, more states 

tested and adopted ETC and extended the 

concept in various ways, including: open 

road tolling, standardized transponders, and 

high occupancy toll lanes. As of 2009, FHWA 

requires all new toll facilities with Federal 

funding to use ETC. Figure 4 shows ETC 

system in use at George Washington Bridge.

Figure 4. Photo. Fully operational ETC at George Washington Bridge in New Jersey. 

© 2013 Johnrob.

TRL Description Requirements

9 Technology refined 

and adopted

• Is the technology deployed in its intended operational environment?

• Is information about the technology disseminated to the

user community?

• Is the technology adopted by the user community?

Implementation

Table 5. Description and requirements of TRL 9.

1. What is a TRL? cont.

TRL GUIDEBOOK 9
10 TRL GUIDEBOOK
Researchers should provide their 

assessment panel with a clear 

understanding of the TRL Scale and 

how it captures the maturity of a technology 

at different stages of development. Next, the 

researchers should present panelists with a 

discussion of several key elements to think 

about as they consider using the TRL Scale to 

assess the research project. If TRL Assessments 

are the right tool for evaluating a project, then 

proper preparation for the assessment will help 

to ensure it is accurate. Preparation involves 

four major components: selecting panelists, 

establishing clear goals for the assessment, 

formalizing timing and location, and creating 

materials, as shown in figure 5.

Selecting Panelists—The Experts and User 

Community

Convening a well-rounded panel of experts to 

assess the maturity of a technology is essential 

to the success of a TRL Assessment. For 

most research projects, a panel of four to six 

stakeholders, researchers, and subject matter 

experts provides an effective balance. Panelists 

should at a minimum be knowledgeable about 

the technology being discussed, the potential 

users of the technology, or the application 

environment. Panel members must not have 

conflicts of interest and must not disclose 

information about intellectual property or 

sensitive information. 

The panel, the Principal Investigator (PI) of 

the project, a notetaker, and at least one 

sponsoring-agency representative should 

attend the TRL Assessment. If possible, 

a neutral moderator should facilitate the 

discussion.

Figure 5. Major components of a TRL Assessment.

GOALS TIMING &

 LOCATION

MATERIALS

PREPARING

FOR THE TRL

ASSESSMENT

PANELISTS

2. Preparing for the TRL Assessment

TRL GUIDEBOOK 11
Establishing Goals—“Why are we 

assessing this technology?”

When conducting TRL Assessments, it is 

important to establish evaluation parameters 

for the discussion. Projects may include many 

different components, and the panel needs a 

clear focus on a distinct technology or set of 

components to assess the research accurately. 

Panel members can be involved in and assist 

with focusing on the technology, and all panel 

members should agree on the goal of the TRL 

Assessment before the assessment begins. 

Further, defining the operating environment is 

key for determining whether the technology 

is a functional tool for the intended user 

community. Before the TRL Assessment, 

all panelists should clearly understand the 

purpose of the TRL Assessment and what 

aspects of the project they will evaluate. 

Formalizing Timing and Location—

The Nuts and Bolts

Timing

A TRL Assessment is most effective if held 

within 4 to 6 months before the end of a 

research project’s funding cycle. At this point, 

the majority of the research will have been 

completed and the TRL Assessment will 

have maximum relevance. This timing also 

presents an opportunity for the research 

team to incorporate the TRL Assessment’s 

findings into any final reports, complete other 

assessments, and find potential followup 

funding sources. 

TRL Assessments usually last from 3 to 

4 hours. However, planners can schedule 

longer meetings to accommodate technology 

demonstrations or laboratory tours or to 

assess complex systems where the panel 

may be considering the maturity of multiple 

components or component integration. 

Location

Location options include the research site, a 

neutral locale, or the funding agency. Typically, 

a TRL Assessment requires only a small, 

audiovisual-capable conference room. Panel 

organizers may also conduct TRL Assessments 

via webinar or teleconference, although 

panelists may consider virtual settings more 

challenging to facilitate an active discussion.

TRL Assessments should be 

focused | Narrow the project down 

into its specific components and 

evaluate their maturity separately 

to draw the most utility from the 

TRL Assessment. Make sure the 

panelists know and agree exactly

on what they are evaluating.

!

Operating Environment | For the 

assessment, be clear about the 

setting or settings in which the 

technology is meant to work. 

!

2. Preparing for the TRL Assessment cont.

12 TRL GUIDEBOOK
Creating Materials—

Getting to the Starting Line 

A comprehensive set of materials is an essential 

foundation for the TRL Assessment panel’s 

discussion. In advance of the TRL Assessment, 

panel members should receive documentation 

of the research project so that they arrive at 

the TRL Assessment with all of the information 

they will need to fairly and fully evaluate the 

maturity of the research. In addition to receiving 

the TRL Scale, the panel should be provided 

with a short framing document that details the 

goals of the TRL Assessment and specifies the 

key technology, applications, and operating 

environments to be assessed during the TRL 

Assessment. 

Creating this framing document for the panel 

often shapes the goals or aims of the TRL 

Assessment, and typically requires a good 

deal of thought and synthesis to succinctly 

describe the research conducted and the critical 

elements of the technology to be reviewed. 

Documentation

Panel organizers provide the panel with—or 

offer them access to—technical deliverables 

for a project, in addition to these framing 

documents. Deliverables may include the 

research project proposal; technical reports 

produced by the research team; and any interim 

and final reports, presentations, or published 

papers. If possible, the project PI should 

complete a “self-assessment” of the project 

using the TRL Scale and share it with the panel 

in advance of the TRL Assessment. This will 

help the PI to better understand the types of 

questions that the panel will be trying to answer 

during the TRL Assessment. 

Review

The panel should be given ample time to 

review the project materials provided. A 

minimum of 1 week should be sufficient time 

for panelists to review and ask any clarifying 

questions that they may have. Convening a 

brief preassessment conference call with the 

panelists approximately 1 week before the 

TRL Assessment is a good way to ensure that 

the panelists understand the TRL Assessment 

process (and to confirm any last-minute 

meeting logistics). This conference call also 

is an opportunity to ask the panelists to 

review the initial TRLs in advance of the panel 

meeting. Having these prediscussion scores 

makes the assessment easier and ensures 

that the panelists have reviewed the project 

documentation in advance of the meeting. 

(The preassessment conference call also is an 

opportunity for panel members to introduce 

themselves, their expertise, and biases relating 

to the technology. This also can take place at the 

start of the panel meeting.)

An example of a Framing 

Document is included in 

appendix A.

2. Preparing for the TRL Assessment cont.

TRL GUIDEBOOK 13
14 TRL GUIDEBOOK
Once the panel members for the TRL 

Assessment have been identified, 

goals have been set, timing and 

location logistics have been confirmed, 

and the materials have been prepared and 

distributed, the day of the TRL Assessment is 

quite straightforward. The PI presents a brief 

technology overview at the beginning of the 

TRL Assessment, the panel deliberates the 

presentation in private, and then the panel 

discusses its findings with the PI. 

It is important to give the panel enough 

time for a robust discussion, but longer TRL 

Assessments are not necessarily better. 

Planners should think about how much time 

will be needed to discuss the technology in an 

efficient and focused manner. Assessments 

should include a well-thought-out agenda.

A sample panel meeting agenda is provided in 

table 6. 

The TRL Assessment process typically begins 

with a brief welcome and broad overview of 

the need that the funded research is trying to 

address. Once this background has been set, 

the panel facilitator introduces the panelists 

and gives them an opportunity to share their 

expertise as it relates to the research project. 

In the absence of a dedicated facilitator, the 

project sponsor may take on this role. 

After introductions, the panel facilitator 

provides a brief overview of the TRL 

Assessment process before the assessment 

begins. After that is complete, the project PI 

provides a technology overview presentation, 

which typically lasts about 60 minutes, 

depending on the complexity of the research 

and testing completed. This presentation 

should detail the technology developed, how 

the technology was tested, and proposed next 

steps. If the project features a research team 

that spans multiple institutions with distinct 

research foci, it may make sense to have the 

PI or co-PI leading each strand of the project 

presentation on their research activities. The 

technology overview portion of the agenda 

should include enough time for clarifying 

questions from the panel, because the PI will 

not be participating in the actual assessment. 

After the PI has completed his or her 

presentation and answered panelist questions, 

3. Conducting a Successful TRL Assessment

Time Agenda Item

9:00 a.m. Welcome and Introduction of Panelists

9:10 a.m. Overview of TRL Assessment Process

9:20 a.m. Technology Overview—PI Presentation with Q&A

10:00 a.m. Technology Readiness Level Deliberation

11:30 a.m. Discussion of TRL Assessment Results with PI + Q&A

Table 6. Example agenda for TRL Assessment panel meeting.

TRL GUIDEBOOK 15
the PI leaves the room and the panelists begin 

deliberations. To begin the assessment portion 

of the agenda, each panelist shares his or her 

initial TRL score for the project and a short 

explanation for why he or she decided on that 

score. This exercise sets a baseline for the panel 

discussion, and the panel begins to deliberate 

the TRL questions one by one to determine a 

final panel score. To increase efficiency, it is 

typically best to begin the discussion at one 

level below the lowest initial TRL—for example, 

the panel can begin its discussion at TRL 4 if the 

lowest initial TRL score is 5. Determining what 

work is required to reach a higher TRL score is 

more important than coming to a consensus on 

an exact score. 

After the panel has concluded its discussions 

and agreed upon a TRL score for the project, 

the PI and project team should rejoin the 

assessment meeting to hear the panel’s 

findings and have an open discussion about 

potential next steps for the research. This is 

an important opportunity for the PI and the 

panel to discuss the project and the PI to learn 

the panel’s thoughts on why the technology’s 

maturity is ranked where it is and how that 

maturity can be improved. 

It is important to document both the panel’s 

discussion as well as the subsequent 

conversation between the panel and the PI. 

The panel facilitator or a notetaker should 

complete a TRL Assessment Report after 

the TRL Assessment has concluded. The TRL 

Assessment Report should include information 

about the goals and technology’s operating 

environment, drawing as necessary from the 

framing document. The report also should 

incorporate comments from the discussion at 

the TRL Assessment, including why the TRL 

score for the project was selected and any 

recommendations for future work. The TRL 

Assessment Report is a useful tool for sharing 

information about the project with potential 

funders of additional work. The report also 

should provide a concise overview of the project 

and next steps. 

An example of a TRL Assessment Report can be found in appendix C.

16 TRL GUIDEBOOK

3. Conducting a Successful TRL Assessment cont. 
T

he results of TRL Assessments can be 

used strategically to support the goals of 

the agency sponsoring the research. For 

example, the Federal Highway Administration 

(FHWA) Exploratory Advanced Research (EAR) 

Program sponsors longer term and higher risk 

research. The program seeks to fund cuttingedge research that can provide improvements 

to national transportation systems. To 

maximize the value of its research and ensure 

that important results are not forgotten, 

the EAR Program uses TRL Assessments 

along with other tools to help identify which 

research products would benefit from followon support and which audiences would be 

interested in the results. TRL Assessments 

provide a useful foundation for the use of 

other research planning and evaluation tools, 

such as logic models and mind maps, by 

subjectively capturing the current level of 

maturity of a research project. In addition, 

because TRL Assessments typically identify 

possible next steps to advance a research 

project to a higher TRL, these assessments 

can be used as the basis for scoping cost 

and level of effort for future research work 

plans. Figure 6 suggests where on the TRL 

Scale various Federal transportation-related 

research programs fall, as well as potential 

hand-off points among funders working at 

different TRLs.

It is important to designate a notetaker in advance of the panel meeting. The notetaker’s job 

will be easier if the person is familiar with the TRL process and technology. It is, therefore, ! important to be clear about technical jargon, acronyms, and implicit assumptions. 

4. Using the Results of TRL Assessments

TRL GUIDEBOOK 17
18 TRL GUIDEBOOK
Conclusion

Technology Readiness 1 2 3 4 5 6 7 8 9

NSF & other Federal Science Programs

FHWA Exploratory Advanced Research 

Program

FHWA Research and Development 

Programs

Small Business Innovation Research 

(SBIR) Phase I

Small Business Innovation Research 

(SBIR) Phase II

Accelerated Innovation Deployment 

Grants

Everyday Counts

NCHRP IDEA

NCHRP

State Planning & Research Program 

(generally)

Transportation Pooled Fund Program

Figure 6. Chart. TRLs across Federal funders in transportation.

T

he TRL Assessments are an important 

instrument for evaluating technology 

maturity within the research and 

development process. TRL Assessments are 

flexible evaluation tools and can be used in 

a variety of settings to fit the needs of the 

agency conducting them. Having a simple 

mechanism to determine and communicate 

technology maturity improves research 

outcomes and program management. 

Technology readiness is measured across a 

spectrum of transportation programs,

as shown in figure 6.

TRL GUIDEBOOK 19
20 TRL GUIDEBOOK
Appendix A.

Technology Framing Documents

Example 1

This sample Technology Framing Document 

highlights circa 1970s RFID technology, the 

predecessor of modern ETC technology.

Technology Overview

RFID technology uses electromagnetic fields to 

identify tags or transponders that are attached to 

certain objects. Tags can be attached to vehicles, 

animals, and other items to be identified by a 

stationary RFID reader. The technology is designed 

to avoid line-of-sight issues and, therefore, the 

transponders can be installed within objects. In 

the early 1970s, the U.S. Department of Energy’s 

Los Alamos National Laboratory initiated research 

into RFID transponder technologies capable of 

communicating specific information, such as a 

tracking identification (ID) or license number, 

when activated by a nearby reader (Landt, 2001). 

While this research focused on tracking of nuclear 

materials, RFID technology may have applications 

in other fields.

Technology Framing

The potential applications of RFID technology can 

be used by transportation agencies, the nuclear 

industry, and the farming industry, among many 

others. Any industry that could benefit from using 

tags to identify objects could use this technology. 

To accurately assess the technological maturity 

of the platform in reference to these use cases, 

the technology must be separated into its core 

components. The components of RFID technology 

include hardware and software (see details below). 

Technology Components

RFID technology consists of the following 

components:

• Hardware.

 – RFID tags and readers.

• Software.

 – RFID software.

Hardware

The RFID system uses fixed readers and RFID 

tags, or transponders. Users program each 

transponder using RFID software, so that fixed 

readers can identify them individually. When a tag 

enters a reader’s field, the system registers that 

tag’s identifier. Depending on the application, this 

trigger can lead to many physical or nonphysical 

actions. The simplest applications are for the tag’s 

identifier to be added to a catalog or displayed on 

a screen. 

Software

RFID software includes a set of codes that 

programs an RFID transponder to emit specific 

identifying information when triggered by an RFID 

reader. 

Technology Readiness Assessment

This Technology Readiness Assessment will 

evaluate the core components of the ETC 

technology, the RFID reader and tag hardware, 

and the RFID software. The assessment panel will 

discuss the maturity of these functions and select 

the appropriate TRL. 

Application

The TRL Assessment will assess the use of the 

RFID technology for identifying vehicles. The 

identifiers for these vehicles will be their tag 

number, along with their vehicle identification 

number. 

Operating Environment 

The intended operating environment is a manned 

gate or checkpoint through which vehicles must 

pass to enter a facility or continue down a road. 

TRL GUIDEBOOK 21
09

Example 2

This sample Technology Framing Document 

describes modern ETC technology. 

Technology Overview

Example Company’s ETC system builds on early

radio transponder and RFID technology to wirelessly 

track vehicles traveling at moderate speeds for 

toll collection purposes. The system is designed to 

improve safety at tolling checkpoints by automating 

toll collection to increase vehicle throughput 

and decrease traffic incidents at checkpoints. A 

secondary result of the system is reduced labor 

costs associated with toll booth staffing. 

Technology Framing

Potential users of the ETC system include state

DOTs, Federal agencies, and large parking facilities

such as those at airports. To accurately assess the 

technological maturity of the platform in reference 

to these use cases, the technology must be 

separated into its core components. The

components of the ETC system include the hardware,

software, and data the system produces. 

Technology Components

The ETC system consists of the following 

components:

• Hardware.

 – RFID tags on individual vehicles

and RFID readers.

 – Roadside cameras for license plate detection.

• Software.

 – Cooperative Operations for Low-Latency 

Electronic Collection of Tolls (COLLECT) software. 

Hardware

The ETC system relies on RFID tags and readers to 

provide vehicle identification and to trigger the toll 

charges. The small RFID tags are located on the 

front windshield of the vehicle, and the readers are 

typically mounted onto a stationary surface (such 

as a toll collection booth or on a gantry mounted 

above the roadway). The readers provide the ETC 

infrastructure, while the RFID tags are used to 

distinguish the vehicles and determine responsibility 

for the charges. Cameras detect and capture license 

plate numbers to confirm and match RFID tags with 

vehicle owners.

Software

The COLLECT software is an online software tool 

meant to standardize and simplify reporting of tolls 

that have been collected and those that need to be 

collected. When an RFID tag triggers an RFID reader, 

an entry is added to the COLL (Commonly Labeled 

List) with the vehicle tag number, time, toll fee, due 

date, and address. The system also automatically 

charges the payment information on file. If none is 

on file, a bill is automatically printed and sent to the 

owner of the vehicle. 

Technology Readiness Assessment

This Technology Readiness Assessment will 

evaluate the core components of the ETC 

technology, the RFID tag and reader and camera 

hardware, and the COLLECT software. The 

assessment panel will discuss the maturity of these 

functions and select the appropriate TRL. 

Application

The TRL Assessment will assess the use of the ETC

system for collecting tolls from drivers automatically. 

Operating Environment 

The intended operating environment is any

roadway that has a need for electronic tolling. 

Appendix A.

Technology Framing Documents cont.

22 TRL GUIDEBOOK
Appendix B.

Principal Investigator Questionnaire

Presentation Preparation Worksheet for 

TRL Assessments

This worksheet is intended for use by PIs and 

presenters as a tool for identifying and organizing 

the specific information that panelists need to 

know before conducting a TRL Assessment. The 

information identified in this worksheet should be 

included in the PI’s or presenter’s 30–45-minute 

PowerPoint presentation, delivered to panelists at 

the start of a TRL Assessment. 

Instructions for Presenters: Answer the following 

questions based on the technology being assessed 

and any testing or prototypes that have been 

developed. Please use this worksheet to inform 

the content of your presentation. 

DEFINITIONAL: What is the technology? Where 

and how is it used? Who is the user? What are the 

subsystems and components of the technological 

system? 

1. Describe the technology.

What is the technology?

Have preliminary engineering designs for system 

components been developed?

Have drawings, diagrams, outlines, or other 

conceptual aids been prepared?

Are there remaining technical or design-related 

challenges? Please describe.

2. Describe the various constituent

parts of the technology. How do

they fit together and interact with

one another?

What are the subsystems and components of 

the technological system? What is the status of 

those subsystems and components?

Table 7. PI Questionnaire.

TRL GUIDEBOOK 23
Your Company Name

3. Describe the envisioned deployment

of this technology. 

Where will this technology be deployed? 

What problem(s) has this technology been 

developed to solve or address? At the point of 

implementation, will this technology address 

these problems sufficiently (if not, why not)?

What is the operational environment for this 

technology (at the point of implementation)?

Describe the end users of the technology, and 

how they will use it.

(From an operational perspective) 

What needs to be done to or with the technology, 

as it exists today, before the technology can be 

deployed in the manner envisioned?

4. How have the technology’s subsystems, 

components, and concepts been

tested (individually)? Please

describe the results.

Have experiments on system components 

been conducted? In what settings were these 

experiments undertaken? 

TESTING: How and where has the technology—and constituent elements—been tested? 

What was the result? How representative is the test environment to the intended operational 

environment?

Appendix B.

Principal Investigator Questionnaire cont.

24 TRL GUIDEBOOK
5. How has the integration of the various 

components and systems been tested?

How will their expected functionality be 

confirmed, both individually and in combination?

6. Has a demonstration of the full 

technology been conducted, or a 

prototype constructed? Please 

describe the results.

What was the scale and setting of the 

demonstration, compared to the envisioned 

deployment of this technology? Was this 

demonstration indicative of how the final 

technology may be expected to perform in

the field?

Have computer simulations for system design, 

construction, or operations been conducted? 

Have case studies been conducted for other 

components of nonhardware or software 

technologies? Please describe the results.

7. Describe the most recent test 

conducted on the full technology. 

What precisely was tested, why, and 

how did it go?

What metrics exist for defining the 

development’s progress for technology?

8. How has the user community 

been included in the technology 

development process?

Have usability experiments been conducted or 

prototypes deployed to intended users?

TRL GUIDEBOOK 25

Appendix B.

Principal Investigator Questionnaire cont.
If prototypes have been produced and fieldtested with the intended end users, do those 

users use the technology as intended? If not, 

how has it been adapted?

If feedback from these users about the 

technology has been received, how has the 

technology been revised (if at all) to address this 

feedback?

(From a “proof-of-functionality” perspective) 

What tests or trials should be performed on, 

with, or using the new technology, as it exists 

today, before the end user can confidently use it? 

Other Notes:

Appendix B.

Principal Investigator Questionnaire cont.

26 TRL GUIDEBOOK
Appendix C.

TRL Assessment Report Example

This document represents a sample TRL 

Assessment Report of ETC technology from the 

mid-1980s, when researchers were piloting the 

initial ETC system.

Technology Readiness Assessment of 

FHWA EAR Program Project

“Example Company: Electronic

Toll Collection”

Introduction

This report summarizes the Technology Readiness 

Level (TRL) Assessment of the Federal Highway 

Administration (FHWA) Exploratory Advanced 

Research (EAR) Program-funded project 

“Electronic Toll Collection” (ETC). On May 11, 1985, 

the EAR Program convened a panel of experts to 

assess the maturity of Example Company’s ETC 

system; specifically, its ability to capture tolling 

moments and collect payment. The intended 

operating environment is any roadway that has a 

need for electronic tolling. 

The remainder of this report provides information 

about the FHWA EAR Program, a summary of the 

TRL Assessment process and the TRL Scale, and 

the proceedings of the assessment panel.

EAR Program Background

The FHWA EAR Program focuses on highrisk, high-reward research that bridges the 

gap between basic and applied research and 

development. It also supports the development 

of transformative research tools that can 

accelerate development of solutions for highwayrelated challenges. In fulfilling its mission, the 

EAR Program identified the need for a system 

to describe the maturity of highway research 

products. Such a system would allow experts and 

nonexperts to: (1) document and communicate 

the maturity of the research at a specific stage of 

development; (2) indicate how the project might 

relate to other research; and (3) determine what 

steps might advance the maturity of a given 

research product. The John A. Volpe National 

Transportation Systems Center developed the TRL 

Scale for the EAR Program with these capabilities 

in mind.

About Technology Readiness Assessments and 

the TRL Scale

TRLs are formal metrics that support assessments 

of a particular technology and provide the ability to 

consistently compare levels of maturity between 

different types of technologies. The TRL Scale uses 

a set of questions designed to measure progress 

of a technology toward maturity. NASA originally 

developed the concept of TRLs. Other Federal 

agencies, notably the U.S. Department of Defense, 

adapted the concept later.

The TRL Scale assesses the maturity of a 

technology in terms of certain characteristics, as 

measured by successful tests. The scale considers 

two aspects of the completed tests:

• How complete was the technology when it was 

tested? (Was it a paper-and-pen concept, a 

system of equations, a component, a subsystem, 

or the complete system?)

• How representative was the test environment?

 – Was it a computer simulation, a controlled 

laboratory experiment, a demonstration at a 

proving ground, or a real-world test?

TRL GUIDEBOOK 27
To use the TRL Scale for successfully evaluating 

a technology, the EAR Program convened a 

panel of outside experts and a project’s principal 

investigator (PI) to review the technology and 

provide an assessment of its maturity, as well as 

to recommended next steps and additional testing 

required to advance the technology to a higher TRL. 

Technology Overview

The ETC system developed by Example Company 

consists of the following subsystem components:

• A small RFID tag that can be read by the RFID 

reader is located within each vehicle. 

• The COLLECT Software (Cooperative Operations 

for Low-Latency Electronic Collection of Tolls) 

is meant to collect all the data associated with 

tolling actions and automatically extract payments 

from existing accounts or distribute notices for 

payment. 

The ETC system relies on RFID tags and readers to 

provide vehicle identification and to trigger the toll 

charges. The small RFID tags are located on the 

front windshield of the vehicle, and the readers are 

typically mounted onto a stationary surface (such 

as a toll collection booth or on a gantry mounted 

above the roadway). The readers provide the ETC 

infrastructure, while the RFID tags are used to 

distinguish the vehicles and determine responsibility 

for the charges. Cameras are used to detect and 

capture license plate numbers to confirm and match 

RFID tags with vehicle owners.

The COLLECT software is an online software tool 

meant to standardize and simplify reporting of tolls 

that have been collected and those that need to be 

collected. When an RFID tag triggers an RFID reader, 

an entry is added to the COLL (Commonly Labeled 

List) with the vehicle tag number, time, toll fee, due 

date, and address. The system also automatically 

charges the payment information on file. If none is 

on file, the system automatically prints and mails a 

bill to the owner of the vehicle. 

Proceedings of the Panel Assessment

EAR Program Manager John Smith opened the 

meeting with a brief discussion of the goals of the 

TRL Assessment process and provided an overview 

of the EAR Program’s role in supporting research 

on the ETC system. The panelists introduced 

themselves and then the panel facilitator outlined 

the structure of the panel assessment. 

The project’s PI, Dr. Jane Doe, presented an overview 

of the research, including summaries of key tests 

conducted over the course of the project. She 

presented examples of how the system—including 

the RFID tags and COLLECT software—works. She 

summarized the project’s accomplishments during 

the research period and highlighted areas for next 

steps.

Following Dr. Doe’s presentation, the panel 

convened to begin the technology readiness 

assessment. The panel—including both in-person 

and remote participants—coalesced around a 

TRL score of 6 or 7 for the Example Company’s 

technology. Following the panel’s discussion, Dr. Doe 

returned to review a summary of the findings and 

the potential next steps for the research suggested 

by the panel. 

Appendix C.

TRL Assessment Report Example cont.

28 TRL GUIDEBOOK
Findings and Recommendations from the

Panel Assessment

Potential applications of the ETC technology 

may be used on any roadway that has a need 

for electronic tolling. Some users may seek to 

decrease congestion caused by manual toll 

systems. Others may want to increase compliance 

and gather data regarding tolls paid. 

The panel determined that the ETC system 

reached a TRL of 7 (prototype demonstrated 

in operational environment). The technology 

operates very well in an operational environment. 

The panel questioned whether limitations in the 

COLLECT system would prohibit linking tolling 

locations. This may lead to an inability to analyze 

system-wide data. 

Possible Next Steps:

1. The panel suggested that more testing be 

done to link separate tolling locations in a 

network. This would allow for system-wide data 

analytics, which may be important to a subset of 

the target audience. 

2. The panel suggested convening a virtual focus 

group of users to provide feedback. 

Lessons Learned for Future Technology Readiness 

Assessments

The participants of the TRL Assessment offered 

feedback on how the TRL Assessment process can 

be improved in the future. The panel suggested 

providing panelists with project information 

further in advance of the panel meeting. Figure 7 

shows an example of a partially marked-up TRL 

scoring sheet. 

Figure 7. Illustration. Sample TRL worksheet.

TRL GUIDEBOOK 29

Appendix C.

TRL Assessment Report Example cont.
30 TRL GUIDEBOOK
Your Company Name 09

Appendix D.

Frequently Asked Questions

1. How long will the assessment take? For every 

panel member, the assessment involves two 

parts: (1) the independent work of reviewing 

the technology and documenting the TRL 

recommendation; and (2) the group work of 

discussing and reconciling different reviewers’ 

perspectives of the technology. The time required 

for each step will depend on the complexity of 

the technology, the richness of the data available 

on it, and the objectives of the review. Simpler 

technologies take less time to review, especially 

if no critical decisions will be made based on 

the scoring discussion. At a minimum, expect 

several hours to review background documents 

or participate in a presentation about the project 

results and several hours to discuss and come 

to a consensus on the TRL. For larger, multiyear 

projects, expect to spend 1 day or more reviewing 

background information and a half-day or more 

participating in an assessment panel.

2. When working through the TRL Scale, do I have 

to start at TRL 1? No. If you have a technology 

that the group believes is fairly close to 

implementation, you may select a higher TRL and 

move forward. You might also find it useful to 

work backward instead. However, if time allows, 

a high-level review of the earlier TRLs may be 

very useful in orienting the team and possibly in 

identifying gaps in the research. 

3. For TRL 4: Is an “integration plan” a plan for 

integrating the technology into the operations of 

the organization? No. In the context of the TRL, 

“integration plan” describes how the technology’s 

components will interface and work together to 

make the technology system operational.

4. For TRL 7: Say we have a technology that is 

clearly at TRL 7 by nearly all counts. Does 

the fact that we never really did laboratory 

testing mean that we should call it a TRL 4? 

That does not make sense. No. If laboratory 

testing was not considered necessary and, 

instead, the technology development team went 

straight to prototype testing in a nonlaboratory 

environment, that does not mean that the 

technology is necessarily at TRL 4. However, it 

does raise the question of what lessons might 

have been learned if laboratory testing had 

been conducted and could point to a need for 

additional testing.

5. For TRL 8: How well must a technology perform 

to confirm that it meets “its stated purpose 

and functionality as designed?” To meet 

this criterion, the technology must operate 

as designed under typical and stress-test 

conditions.

6. For TRL 8: If target performance measures were 

never clearly defined or documented, does that 

mean that TRL 8 has not been achieved? Target 

performance measures are metrics that describe 

the intended functionality of the technology. If 

“desired performance” was defined only loosely, 

then technologies that meet that vaguely defined 

state can achieve TRL 8.

7. For TRL 9: How broadly must the technology 

be adopted to reach TRL 9? This will vary 

considerably depending on the goals of the 

project. Broad adoption is not required. 

TRL GUIDEBOOK 31
32 TRL GUIDEBOOK
Appendix E. Example Projects and

Associated Technology Readiness Levels

Research Product to be Assessed: A “guidebook” for designing, constructing, and reusing 

bridge systems that address rapid renewal needs. Includes detailed plans for light, simple 

bridges that are easier to design, fabricate, transport, and erect than traditional bridges. 

Features concepts for innovative foundation systems, sub- and super-structure systems, 

subsystems, and components.

Technology “As Implemented” (TRL 9): A printed or software guidebook that describes 

recommended best practices for accelerated bridge construction and installation.

Level Operating Environment Technology to be Assessed 

TRL 2-5

Laboratory Environment: A simulation 

or small-scale project. The user likely 

would be a member of the guidebook 

development team.

Components: The translation of the case 

studies into the guidance provided by the 

guidebook.

TRL 6

Relevant Environment: A single fullscale construction project on a controlled 

site, with project managers familiar with 

the guidebook and in contact with the 

development team.

Prototype: Case studies of bridge designs 

or aspects of design technique, and the 

logical organization and presentation of that 

knowledge base.

TRL 7-9

Operational Environment: The application 

of the guidebook to a physical project: 

a span of 100 to 400 ft, in nonwinter 

weather, in rural and urbanized areas 

throughout the United States, regardless 

of development density or traffic density. 

The user might be a state Department 

of Transportation engineer with bridge 

design experience overseeing the 

construction and installation of a bridge.

Technology: The complete guidebook and any 

ancillary material needed for its use.

Project Web site: http://www.trb.org/Main/Blurbs/168046.aspx.

Table 8. Example 1. Innovative bridge design and rapid renewal: design tool kit.

TRL GUIDEBOOK 33
Research Product to be Assessed: A software program to predict driver and autonomous 

vehicle response to different combinations of visual guidance—such as centerlines, edge 

lines, delineators, and raised pavement markers—to navigate curves in the roadway.

Technology “As Implemented” (TRL 9): An advisory software-based tool that helps 

designers specify the parameters of a new roadway.

Levels Operating Environment Technology to be Assessed 

TRL 2-5

Laboratory Environment: The PC on 

which the software was developed, 

operated by one of the developers.

Components: Algorithms describing the 

visibility of certain marking types under design 

conditions, software-based implementation 

of those algorithms, subroutines for the 

presentation of the material and acceptance 

of user input, installation packages, and any 

instructions.

TRL 6

Relevant Environment: A PC used by a 

staff member not on the development 

team.

Prototype: The software absent some 

functionality and without adequate 

documentation; the “alpha” or “beta” version.

TRL 7-9

Operational Environment: A PC usable by 

any roadway engineer with no experience 

in roadway design software.

Technology: The software, including installation 

packages and user manual.

Project Web site: http://www.fhwa.dot.gov/advancedresearch/

pubs/seedarkear.cfm.

Table 9. Example 2. Increased understanding of driver visibility requirements.

Appendix E. Example Projects and

Associated Technology Readiness Levels cont.

34 TRL GUIDEBOOK
Research Product to be Assessed: A Bluetooth-based tool that accurately measures travel 

time and arterial or freeway traffic.

Technology “As Implemented” (TRL 9): A hardware or software system that provides traveltime estimates to travelers and traffic management centers.

Level Operating Environment Technology to be Assessed 

TRL 2-5

Laboratory Environment: A bench 

test for individual Bluetooth sensors 

or a small network of sensors. The 

software developer or someone else 

knowledgeable about its operation 

conducts the software testing.

Components: Bluetooth sensors, installation 

hardware, data transmission, analysis, storage 

hardware or software, and user interface 

software.

TRL 6

Relevant Environment: A pilot test of 

a small network of Bluetooth traffic 

sensors in a parking lot generating data 

that, when processed, produces traveltime estimates. The software might be 

poorly documented and usable only by 

knowledgeable staff.

Prototype: A complete system—with 

all necessary parts in place—but with 

nonweather-resistant sensor housing and 

functional, but flawed, software.

TRL 7-9

Operational Environment: The physical 

environment in which the fully functional 

Bluetooth sensors will operate (e.g., 2- 

to 6-lane roads in any U.S. metropolitan 

area). The software environment in which 

sensor data is processed and transmitted 

(e.g., wireless transmission to PCs for 

data processing and distribution) to 

the user (i.e., Metropolitan Planning 

Organization staff or the traveling public).

Technology: A system composed of Bluetooth 

sensors, data transmission and storage 

equipment, software to convert the data into 

travel-time estimates and present them to 

users, and any necessary users’ guides.

Project Web site:

http://www.sbir.gov/content/anonymoustraffic-probes-travel-time-and-o-d-usingbluetooth-ids-0.

Table 10. Example 3. Anonymous traffic probes for travel time

and origin-destination using Bluetooth IDs.

TRL GUIDEBOOK 35

Appendix E. Example Projects and

Associated Technology Readiness Levels cont.
36 TRL GUIDEBOOK
Your Company Name 09

Table 11. TRL Scale: Descriptions and requirements.

Appendix F. TRL Scale

TRL Description To achieve the given TRL, you must answer yes to EVERY 

question. Discuss any uncertain answers.

Basic Research 1 Basic principles and 

research

• Do basic scientific principles support the concept?

• Has the technology development methodology or approach been developed?

2 Application formulated • Are potential system applications identified?

• Are system components and the user interface at least partly described?

• Do preliminary analyses or experiments confirm that the application might 

meet the user need?

3 Proof of concept • Are system performance metrics established? 

• Is system feasibility fully established?

• Do experiments or modeling and simulation validate performance predictions 

of system capability?

• Does the technology address a need or introduce an innovation in the field of 

transportation?

Applied Research 4 Components validated in 

laboratory environment

• Are end-user requirements documented?

• Does a plausible draft integration plan exist, and is component compatibility 

demonstrated?

• Were individual components successfully tested in a laboratory environment

(a fully controlled test environment where a limited number of critical 

functions are tested)?

5 Integrated components 

demonstrated in a 

laboratory environment

• Are external and internal system interfaces documented?

• Are target and minimum operational requirements developed?

• Is component integration demonstrated in a laboratory environment (i.e., 

fully controlled setting)?

Development 6 Prototype demonstrated 

in relevant environment

• Is the operational environment (i.e., user community, physical environment, 

and input data characteristics, as appropriate) fully known?

• Was the prototype tested in a realistic and relevant environment outside the 

laboratory?

• Does the prototype satisfy all operational requirements when confronted 

with realistic problems?

7 Prototype demonstrated 

in operational 

environment

• Are available components representative of production components?

• Is the fully integrated prototype demonstrated in an operational 

environment (i.e., real-world conditions, including the user community)?

• Are all interfaces tested individually under stressed and anomalous 

conditions?

8 Technology proven in 

operational environment

• Are all system components form-, fit-, and function-compatible with each 

other and with the operational environment?

• Is the technology proven in an operational environment (i.e., meet target 

performance measures)?

• Was a rigorous test and evaluation process completed successfully?

• Does the technology meet its stated purpose and functionality as designed?

Implementation 9 Technology refined and 

adopted

• Is the technology deployed in its intended operational environment?

• Is information about the technology disseminated to the user community?

• Is the technology adopted by the user community?

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Appendix G. Additional Resources on the TRL 

Scale and the Use of TRLs for Assessment

For more information about TRLs and TRL 

Assessments, please visit the following:

• GAO report on TRL use: http://www.gao.gov/

products/NSIAD-99-162. 

• TRB paper comparing TRLs with other 

research assessment tools. Corporate Authors: 

Transportation Research Board, Washington, DC. 

Authors: Cuddy, Matt; Towery, Nate Deshmukh; 

Machek, Elizabeth; Myers, Jarred. Conference: 

Transportation Research Board 96th Annual 

Meeting. Publication Date: 2017. Monograph Title: 

TRB 96th Annual Meeting Compendium of Papers.

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40 TRL GUIDEBOOK
09

Glossary of Terms

and Acronyms

COLL: Commonly Labeled List 

COLLECT software: Cooperative Operations for Low-Latency Electronic Collection of Tolls 

Deployment: The inception of a technology into its intended technology system

EAR: Exploratory Advanced Research 

ETC: Electronic Toll Collection 

FHWA: Federal Highway Administration

Framing Document: A short document that details the goals of the TRL Assessment and specifies the key 

technology, applications, and operating environments to be assessed during the TRL Assessment

GAO: Government Accountability Office

ID: Identification 

NASA: National Aeronautics and Space Administration

NCHRP: National Cooperative Highway Research Program

NCHRP IDEA: NCHRP Innovations Deserving Exploratory Analysis

NSF: National Science Foundation

PC: personal computer

PI: Principal Investigator

Q&A: questions and answers

RFID: radio-frequency identification 

SBIR: Small Business Innovation Research 

TRB: Transportation Research Board

TRL: Technology Readiness Level 

TRL Scale: Formal metrics for assessing a particular technology on its maturity level

TRL GUIDEBOOK 41
42 TRL GUIDEBOOK
References

Cardullo, M. (2003). Genesis of the Versatile RFID. 

RFID Journal, obtained from http://www.rfidjournal.

com/articles/view?392, last accessed July 19, 2017.

Landt, J. (2001). Shrouds of Time: The History of 

RFID. Association for Automatic Identification 

and Data Capture Technologies, PDF, obtained 

from http://www.transcore.com/wp-content/

uploads/2017/01/History-of-RFID-White-Paper.

pdf, last accessed July 20, 2017.

North Texas Tollway Authority. (n.d.). Milestones.

Obtained from https://www.ntta.org/whoweare/

milestones/Pages/default.aspx, last accessed July 

21, 2017.

Transportation Research Board. (2016). Technology 

Readiness Level Assessments for Research Program 

Managers and Customers, Webinar presentation, 

obtained from http://onlinepubs.trb.org/Onlinepubs/

webinars/160428.pdf, last accessed July 19, 2017.

Vickrey, W.S. (1963). Pricing in Urban and Suburban 

Transport. Papers and Proceedings of the SeventyFifth Annual Meeting of the American Economic 

Association. The American Economic Review, 53(2), 

452-465.

Violino, B., Roberti, M. (2005). The History of RFID 

Technology. RFID Journal, obtained from http://www.

rfidjournal.com/articles/view?1338, last accessed 

July 19, 2017.

United States Patent and Trademark Office. 

(1971). Automatic toll charging system, U.S. Patent 

3602881, obtained from https://www.google.com/

patents/US3602881, last accessed December 13, 

2017.

U.S. Department of Transportation. (2016). History 

of Intelligent Transportation Systems. Publication No.: 

FHWA-JPO-16-329.

TRL GUIDEBOOK 43
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TRL GUIDEBOOK 45

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TRL SCALE LEVELS

BASIC RESEARCH

DEVELOPMENT IMPLEMENTATION

APPLIED RESEARCH

7

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Technology proven in 

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Components validated in 

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Basic principles and research

Integrated components demonstrated in a 

laboratory environment

Prototype demonstrated in operational environment

Technology refined and adopted
TRL GUIDEBOOK 46

EXPLORATORY ADVANCED RESEARCH

FHWA-HRT-17-047

HRTM-30/09-17(500)E.