Roadway lighting sources are being converted from high pressure sodium (HPS) and other high-intensity discharge (HID) luminaires to light emitting diode (LED) luminaires because LEDs are generally more energy efficient and may offer better visibility. LEDs with a correlated color temperature (CCT) greater than 3000K often have higher blue content in their spectrum (460 to 480 nm) than HPS lamps. Light in this wavelength affects the production of the hormone melatonin, which regulates the human circadian rhythm. In June 2016, the American Medical Association (AMA) issued a report (The Council on Science and Public Health Report 2-A-16, Human and Environmental Effects of Light Emitting Diode (LED) Community Lighting) noting that roadway lighting with higher blue content, such as the light produced by LEDs with higher CCTs, could adversely suppress melatonin and affect the sleep health of people exposed to it. However, a link between melatonin suppression and LED lighting at roadway levels has never been reported. There could, however, be an advantage to the blue content in the LEDs. Because the blue content in LEDs has the potential to suppress melatonin, then by extension it may have the potential to make drivers more alert.
In order to design LED roadway lighting that minimizes any negative impacts on drivers, research is needed to understand the relationship between LED roadway lighting and driver sleep health and alertness.
The objective of this research is to develop a guidance document for state DOTs that (1) describes the effects of LED roadway lighting on the sleep health and alertness of drivers, with attention to the illuminance, duration, and spectral power distribution (SPD) of the LED lighting; (2) compares these effects to those of (a) high-intensity discharge (HID) lighting and (b) the absence of roadway lighting; and (3) suggests methods to mitigate the effects, if any, of LED roadway lighting on sleep health and alertness. In this research, the term “sleep health” shall be construed to mean circadian disruption.
Proposers are asked to provide a detailed research plan for accomplishing the project objective and for producing the deliverables required by each phase of the project. 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 objective. The work proposed for each phase must be divided into tasks and proposers must describe the work proposed in each task in detail.
Deliverables shall include, at a minimum:
1. A critical review of the literature (with particular attention to that published since 2014) on the potential effects of the SPD, illuminance, and duration of LED lighting at roadway levels on human sleep health and alertness, with attention to the measurement methodology.
2. A proposed Phase II work plan to experimentally determine:
· Typical levels of corneal illuminance and typical durations of exposure from LED roadway lighting as a function of SPD compared to that from common LED devices such as tablets, TVs, phones, and dashboards, as well as from low-beam and high-beam HID and LED vehicle headlamps.
· The threshold of corneal illuminance from LED roadway lighting necessary to produce a measurable effect—objective, subjective, or both—on the sleep health and alertness of a vehicle operator as a function of SPD and duration.
· How these effects compare to those of HID lighting and of the absence of roadway lighting.
Note: Simple pre- and post-exposure measurements of physiological markers such as blood levels of melatonin and body temperature alone are not sufficient to establish thresholds.
3. An interim report that presents the critical literature review and the proposed Phase II work plan.
Note: The contractor shall meet with NCHRP within 1 month of submitting the Phase I interim report to obtain approval to conduct Phase II.
1. Execution of the work plan approved in Phase I.
2. A guidance document for state DOTs that presents (a) the thresholds (objective, subjective, or both) of LED roadway lighting at which effects are seen on driver sleep health and alertness; (b) comparison of these thresholds with typical exposure from other common LED devices as well as from HID roadway lighting and from the absence of roadway lighting; and (c) suggested methods to mitigate the effects, if any, of LED roadway lighting on sleep health and alertness.
Note: The guidance shall be prepared in the format of an AASHTO guide or report.
3. A final report that documents results, summarizes findings, draws conclusions, and presents (a) the guidance document for state DOTs and (b) suggestions for needed future research on this topic.
A. The proposal, including appendices, shall not exceed 35 single-spaced pages; the Research Plan, Item 4 of the proposal, shall not exceed 15 single-spaced pages, in 12-point font or larger.
B. For budgeting purposes, proposers should plan for one in-person meeting with NCHRP in Washington, DC or Irvine, CA.
C. Proposals should include a task-by-task breakdown of labor hours for each staff member as shown in Figure 4 in the brochure, "Information and Instructions for Preparing Proposals" (http://onlinepubs.trb.org/onlinepubs/crp/docs/ProposalPrep.pdf). 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.
D. The NCHRP is a practical, applied research program that produces implementable products addressing problems faced by transportation practitioners and managers. The benefits of NCHRP research are realized only when the results are implemented in state DOTs and other agencies. Implementation of the research product must be considered throughout the process, from problem statement development to research contract and beyond completion of the research. Item 4(c), "Anticipated Research Results," must include the following: (a) the "product" expected from the research, (b) the audience or "market" for this product, (c) a realistic assessment of impediments to successful implementation, and (d) the institutions and individuals who might take leadership in deploying the research product. The project panel will develop and maintain an implementation plan throughout the life of the project. 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.
E. Item 5 in the proposal, "Qualifications of the Research Team," must include a section labeled "Disclosure." Information relevant to the NCHRP's need to ensure objectivity and to be aware of possible sources of significant financial or organizational conflict of interest in conducting the research must be presented in this section of the proposal. For example, under certain conditions, ownership of the proposing agency, other organizational relationships, or proprietary rights and interests could be perceived as jeopardizing an objective approach to the research effort, and proposers are asked to disclose any such circumstances and to explain how they will be accounted for in this study. If there are no issues related to objectivity, this should be stated.
F. Proposals are evaluated by the NCHRP staff and project panels consisting of individuals collectively very knowledgeable in the problem area. Selection of an agency is made by the project panel 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) the proposer's plan for participation by Disadvantaged Business Enterprises--small firms owned and controlled by minorities or women; and (6) the adequacy of the facilities.
Note: The proposer's plan for participation by Disadvantaged Business Enterprises should be incorporated in Item 12 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 Academies of Sciences, Engineering, and Medicine. 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 Academies of Sciences, Engineering, and Medicine. 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.