The National Academies

NCHRP 03-149 [RFP]

Evaluation of the Traffic Signal Timing Manual, Third Edition

Posted Date: 12/13/2022

  Project Data
Funds: $750,000
Contract Time: 24 months
(includes 1 month for NCHRP review and approval of each interim report and 3 months for NCHRP review and for contractor revision of the final report)
Authorization to Begin Work: 7/1/2023 -- estimated
Staff Responsibility: Dr. Zuxuan Deng
   Phone: 2023342305
   Email: zdeng@nas.edu
RFP Close Date: 1/31/2023
Fiscal Year: 2023


The Federal Highway Administration (FHWA) Traffic Signal Timing Manual (STM) has been the most widely accepted reference across the traffic signal timing field. Since the release of the second edition in 2015 (STMv2), there have been significant advances in signal timing research and practices, and several NCHRP and FHWA initiatives have been implemented.

·       NCHRP Project 03-125, “Evaluation of Change and Clearance Intervals Prior to the Flashing Yellow Permissive Left-Turn Indication” evaluates change and clearance intervals prior to flashing yellow arrow (FYA).

·       NCHRP Research Report 954: Performance-Based Management of Traffic Signals compiles the best available information on automated traffic signal performance measures and management strategies for traffic signal operations.

·       NCHRP Web-only Document 284: Decision-Making Guide for Traffic Signal Phasing provides guideline for traffic signal phasing.

·       NCHRP Research Report 969: Traffic Signal Control Strategies for Pedestrians and Bicyclists addresses the multimodal signal timing for nonmotorized users.

·       NCHRP Research Report 959: Diverging Diamond Interchange Information Guide, second edition, presents a comprehensive guide to the design and operation of diverging diamond interchanges (DDI).

·       NCHRP Project 03-136, “Evaluating the Performance of Right-Turn-On-Red Operation at Signalized Intersections” addresses performance of right-turn-on-red operations.

·       Traffic Signal Management Plan Guidance Document (FHWA-HOP-15-038).

·       Traffic Signal Management and Capability Maturity Framework (CMF, FHWA-HOP-16-028).

·       Promotion of basic service model concept (FHWA-HOP-09-055) highlighting the need to scale equipment and operations based on agency staff.

Major industry references and standards have been updated with new computational methods and operational practices incorporated.

·       Highway Capacity Manual, sixth edition, (HCM6-2016) provides updated procedures for computing the capacity of various highway facilities including signalized intersections.

·       NEMA-TS2-2016 Standard incorporates FYA feature, as well as associated configuration and other related information.

·       NTCIP 1202 v03A-2019 has updated clauses on FYA and other corrections related to signal operations.

New technological trends are emerging, such as applying new computational approaches to the signal timing process, developing signal timing plans using novel datasets, and implementing new signal timing paradigms for connected and autonomous vehicles (CAV) and connected intersections. The traffic signal timing community has highlighted important topics to be addressed in a new version of the STM, including the signal timing of unconventional intersection geometries; advanced bicycle, pedestrian, and transit signal timing; cybersecurity risks tied to the signal timing procedures; and innovative signal timing design using standards-based controller features.

The STM has served as a primary reference for the FHWA Traffic Signal Timing Concepts course. The course presents a signal timing workflow that starts with goals, explores context with a focus on vehicle flow, and then selects strategies and tactics that support attainment of objectives.  It is envisioned that an update to the STM’s structure could better support this workflow, inclusive of performance measurement to validate objectives and demonstrate progress towards goals and enhance the coverage of pedestrians, bicycles, transit, Complete Streets, safety, and equity. The update should consider how signal timing fits in with the overall traffic signal program, as other elements within the program (e.g., maintenance, equipment health) may directly impact the success of signal timing activities.


The objective of this research is to provide guidance on utilizing up-to-date effective practices and research outcomes that have been successfully implemented after STMv2. At the minimum, the research shall:

  • Support an objectives-oriented, actively managed traffic signal timing process that starts with goals, considers context, supports the implementation of strategies and tactics, and addresses evaluation of signal timing design outcomes, 
  • Address signal timing strategies for various intersection and roadway network users, including nonmotorized users and transit vehicles,
  • Incorporate existing research and effective practices to expand the coverage of over-saturated/congested conditions, and
  • Describe use cases for advanced/innovative controller features, such as peer-to-peer communication, custom logic, etc.


Accomplishment of the project objective will require completion of the following tasks, at a minimum.




Task descriptions are intended to provide a framework for conducting the research. The NCHRP is seeking the insights of proposers on how best to achieve the research objective. Proposers are expected to describe research plans that can realistically be accomplished within the constraints of available funds and contract time. Proposals must present the proposers' current thinking in sufficient detail to demonstrate their understanding of the issues and the soundness of their approach to meeting the research objective. 


PHASE I – Planning 


Task 1. Review the pertinent literature on traffic signal timing policies, practices, and techniques; the latest industry standards; and the safety and operational impacts of signal timing decisions. Identify ongoing, relevant research projects and obtain any interim materials, if available.  Identify any needed coordination with other ongoing research projects.

Task 2. Develop and employ methods to gain the input of a representative group of practitioners that have firsthand knowledge of the use and application of the STM to gain insights on gaps, and opportunities to improve the content, structure, and range of topics covered in the proposed update.

Task 3 Submit a white paper identifying topics in STMv2 that the research results may influence and new topics for the next update of the STMv2. In addition to those developed through Tasks 1 and 2, it is expected the following topics, at a minimum, will be considered:

·       Signal phasing and overlaps

·       Multimodal users

·       Signal timing strategies for oversaturated conditions

·       Interchanges, ramp terminals

·       Unconventional intersection geometries

·       Priority and preemption

·       Automated Traffic Signal Performance Measures (ATSPM) and other performance management approaches

·       Peer-to-peer

·       Custom logic

·       CAV

·       Cybersecurity

·       Detection

·       Signal timing strategies associated with highway traffic signals that are not traffic control signals (e.g., lane control signals, pedestrian hybrid beacons, ramp meters)

The white paper should assess the maturity and supporting reference material for all proposed topics. For topics not deemed mature, the contractor should discuss research gaps and recommend a strategic approach for addressing these items that includes identifying organizations that might champion these items and advance them to maturity. Discuss the white paper with the project panel in a conference call and finalize a list of topics that have sufficient content for consideration and further development in this project.

Task 4. Prepare Interim Report No. 1 that includes an approach to develop the report addressing the areas approved by the panel in Task 3, and an annotated outline of the manual. The approach should identify appropriate format(s) for the next update of the STMv2 that can accommodate various ways the manual is used and can be made available to users in a sustained manner. The approach must also describe the methodology and rationale for the work proposed for Phase II. 

Note: Following a 1-month review of Interim Report No. 1 by the NCHRP, the research team will be required to meet virtually with the NCHRP project panel to discuss the interim report. Work on Phase II of the project will not begin until authorized by the NCHRP. 



PHASE II – Execution  


Task 5. Based on the approved Interim Report No. I, prepare draft language for consideration by FHWA to incorporate the research results in the next update of the STMv2 (herein called FHWA Deliverable) and update all relevant references. The FHWA Deliverable should address all stated project objectives and cover all topics identified through Task 3. The FHWA Deliverable should continue to (1) provide material instrumental to agencies for their own signal timing policies and practices, (2) facilitate the training of new staff, (3) facilitate implementation of more advanced signal timing concepts where appropriate, (4) include examples that illustrate application of the manual material to real-world intersections and roadway networks, (5) include references that promote a deeper understanding of topics, and (6) utilize graphics to help illustrate concepts.

Task 6. Submit a plan for media and communication material to be developed for the project panel’s approval. At a minimum, media and communication materials should include a series of concise videos that demonstrate practitioner uses of the material in the FHWA Deliverable, a two-page executive level flyer describing the practice of signal timing and its benefits, and a syllabus and "train the trainer" materials in PowerPoint format with speaker notes for agencies to incorporate into their training programs.

Task 7. Prepare and submit a revised draft FHWA Deliverable based on the project panel’s review comments

Task 8. Present the research findings to appropriate American Association of State Highway and Transportation Officials (AASHTO) technical committees for comments and propose any revisions to NCHRP. The research team should anticipate making two presentations during the research to appropriate technical committees at annual meetings of the AASHTO Committee on Traffic Engineering and Committee on Transportation System Operations. Revise the draft FHWA Deliverable after consideration of review comments.  

Task 9. Prepare the final deliverables including the following: 

1.    A conduct of research report that documents the entire research effort, any lessons learned, and a list of potential future enhancements to STM;  

2.    The proposed FHWA Deliverable;

3.    Media and communication materials as approved in Task 6; and 

4.    A stand-alone technical memorandum titled “Implementation of Research Findings and Products.” See Special Note I for additional information. Additional funding may be available for a follow-up contract on the implementation of the results.


Note: Following receipt of the draft final deliverables, the remaining 3 months shall be for NCHRP review and comment and for research agency preparation of the final deliverables.  





A. The Information and Instructions for Preparing Proposals for the Transportation Research Board’s Cooperative Research Programs were revised in May 2022. Please take note of the new and revised text which is highlighted in yellow.  


B. Proposals must be submitted as a single PDF file with a maximum file size of 10 MB. The PDF must be formatted for standard 8 ½” X 11” paper, and the entire proposal must not exceed 60 pages (according to the page count displayed in the PDF). Proposals that do not meet these requirements will be rejected. For other requirements, refer to chapter V of the instructions. 


C. The Information and Instructions for Preparing Proposals for the Transportation Research Board’s Cooperative Research Programs have been modified to include a revised policy and instructions for disclosing Investigator Conflict of Interest. For more information, refer to chapter IV of the instructions. A detailed definition and examples can be found in the CRP Conflict of Interest Policy for Contractors. The proposer recommended by the project panel will be required to submit an Investigator Conflict of Interest and Disclosure Form as a prerequisite for contract negotiations.  


D. Proposals will be rejected if any of the proposed research team members’ work for organizations represented on the project panel. The panel roster for this project can be found at https://www.mytrb.org/OnlineDirectory/Committee/Details/6762. Proposers may not contact panel members directly; this roster is provided solely for the purpose of avoiding potential conflicts of interest.  


E. Proprietary Products - If any proprietary products are to be used or tested in the project, please refer to Item 6 in the Information and Instructions for Preparing Proposals. 


F. Proposals are evaluated by the NCHRP staff and project panels consisting of individuals collectively knowledgeable in the problem area. The project panel will recommend their first choice proposal considering the following factors: (1) the proposer's demonstrated understanding of the problem; (2) the merit of the proposed research approach and experiment design; (3) the experience, qualifications, and objectivity of the research team in the same or closely related problem area; (4) the plan for ensuring application of results; (5) how the proposer approaches inclusion and diversity in the composition of their team and research approach, including participation by certified Disadvantaged Business Enterprises; and, if relevant, (6) the adequacy of the facilities. A recommendation by the project panel is not a guarantee of a contract. The National Academy of Sciences (NAS - the contracting authority for the National Academies of Sciences, Engineering, and Medicine) will conduct an internal due diligence review and risk assessment of the panel’s recommended proposal before contract negotiations continue.  


Note: The proposer's approach to inclusion and diversity as well as participation by Disadvantaged Business Enterprises should be incorporated in Item 11 of the proposal. 


G. Copyrights - All data, written materials, computer software, graphic and photographic images, and other information prepared under the contract and the copyrights therein shall be owned by the National Academy of Sciences. The contractor and subcontractors will be able to publish this material for non-commercial purposes, for internal use, or to further academic research or studies with permission from TRB Cooperative Research Programs. The contractor and subcontractors will not be allowed to sell the project material without prior approval by the National Academy of Sciences. By signing a contract with the National Academy of Sciences, contractors accept legal responsibility for any copyright infringement that may exist in work done for TRB. Contractors are therefore responsible for obtaining all necessary permissions for use of copyrighted material in TRB's Cooperative Research Programs publications. For guidance on TRB's policies on using copyrighted material please consult Section 5.4, "Use of Copyrighted Material," in the Procedural Manual for Contractors. 


H. Proposals should include a task-by-task breakdown of labor hours for each staff member as shown in Figure 4 in the Information and Instructions for Preparing Proposals. Proposals also should include a breakdown of all costs (e.g., wages, indirect costs, travel, materials, and total) for each task using Figures 5 and 6 in the brochure. Please note that TRB Cooperative Research Program subawards (selected proposers are considered subawards to the National Academy of Sciences, the parent organization of TRB) must comply with 2 CFR 200 – Uniform Administrative Requirements, Cost Principles, and Audit Requirements for Federal Awards. These requirements include a provision that proposers without a "federally" Negotiated Indirect Costs Rate Agreement (NICRA) shall be subject to a maximum allowable indirect rate of 10% of Modified Total Direct Costs. Modified Total Direct Costs include all salaries and wages, applicable fringe benefits, materials and supplies, services, travel, and up to the first $25,000 of each lower tier subaward and subcontract. Modified Total Direct Costs exclude equipment, capital expenditures, charges for patient care, rental costs, tuition remission, scholarships and fellowships, participant support costs and the portion of each lower tier subaward and subcontract in excess of $25,000. 


I. The required technical memorandum titled “Implementation of Research Findings and Products” should (a) provide recommendations on how to best put the research findings/products into practice; (b) identify possible institutions that might take leadership in applying the research findings/products; (c) identify issues affecting potential implementation of the findings/products and recommend possible actions to address these issues; and (d) recommend methods of identifying and measuring the impacts associated with implementation of the findings/products. Implementation of these recommendations is not part of the research project and, if warranted, details of these actions will be developed and implemented in future efforts. 


The research team will be expected to provide input to an implementation team consisting of panel members, AASHTO committee members, the NCHRP Implementation Coordinator, and others in order to meet the goals of NCHRP Active Implementation: Moving Research into Practice, available at http://onlinepubs.trb.org/onlinepubs/nchrp/docs/NCHRP_ActiveImplementation.pdf 


J. If the team proposes a Principal Investigator who is not an employee of the Prime Contractor, or if the Prime Contractor is proposed to conduct less than 50% of the total effort (by time or budget), then section five of the proposal should include: (1) a justification of why this approach is appropriate, and (2) a description of how the Prime Contractor will ensure adequate communication and coordination with their Subcontractors throughout the project. 


K. All budget information should be suitable for printing on 8½″ x 11″ paper. If a budget page cannot fit on a single 8½″ x 11″ page, it should be split over multiple pages. Proposers must use the Excel templates provided in the Information and Instructions for Preparing Proposals for the Transportation Research Board’s Cooperative Research Programs 


Proposals must be uploaded via this link: https://www.dropbox.com/request/M0rrabdkox3FHjseo2k2 
Proposals are due not later than 5:00 p.m. Eastern Time on 1/31/2023.

This is a firm deadline, and extensions are not granted. In order to be considered for award, the agency's proposal accompanied by the executed, unmodified Liability Statement must be in our offices not later than the deadline shown, or the proposal will be rejected.

Liability Statement

The signature of an authorized representative of the proposing agency is required on the unaltered statement in order for TRB to accept the agency's proposal for consideration. Proposals submitted without this executed and unaltered statement by the proposal deadline will be summarily rejected. An executed, unaltered statement indicates the agency's intent and ability to execute a contract that includes the provisions in the statement.

Here is a fillable PDF version of the Liability Statement. A free copy of the Adobe Acrobat PDF reader is available at https://www.adobe.com.

General Notes

1. According to the provisions of Title 49, Code of Federal Regulations, Part 21, which relates to nondiscrimination in federally assisted programs, all parties are hereby notified that the contract entered into pursuant to this announcement will be awarded without discrimination on the grounds of race, color, religion, sex, national origin, or disability.

2. The essential features required in a proposal for research are detailed in the current brochure entitled "Information and Instructions for Preparing Proposals". Proposals must be prepared according to this document, and attention is directed specifically to Section V for mandatory requirements. Proposals that do not conform with these requirements will be rejected.

3. The total funds available are made known in the project statement, and line items of the budget are examined to determine the reasonableness of the allocation of funds to the various tasks. If the proposed total cost exceeds the funds available, the proposal is rejected.

4. All proposals become the property of the Transportation Research Board. Final disposition will be made according to the policies thereof, including the right to reject all proposals.

5. Potential proposers should understand that follow-on activities for this project may be carried out through either a contract amendment modifying the scope of work with additional time and funds, or through a new contract (via sole source, full, or restrictive competition).

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