BACKGROUND

Traffic intrusions into work zones present a significant safety risk to construction, maintenance, and utility workers. According to the Bureau of Labor Statistics Census of Fatal Occupational Injuries, struck-by crashes are a major cause of roadway construction worker deaths. A 2019 Associated General Contractors (AGC) of America survey found that 67 percent of contractors reportedly had a vehicle intrusion into one of their work zones during the year. It was also reported that eight percent of respondents had one of their workers killed in a work zone crash, and 28 percent had a worker injured by a vehicle in the work zone. Motorists are also at risk when intruding into a work zone, potentially colliding with work equipment and materials.

In addition, data are not available on the number of intrusions that occur, but do not result in a crash because the driver is able to turn the vehicle back into the travel lane. There is an immediate need to evaluate existing and develop new prediction models to estimate the likelihood of work zone intrusions to improve work zone safety management. The prediction model should reflect intrusion potential into work zones that are in travel lanes, have lane shifts, or have other work zone features that may influence intrusion risks.

OBJECTIVE

The objective of this project is to develop a guide to (1) assist state departments of transportation (DOTs) and local agencies to estimate the likelihood of work zone intrusions to improve work zone safety management and decision-making, and (2) develop countermeasures including prevention and mitigation strategies. At a minimum, the research team shall:

1.  Determine the frequency and characteristics of work zone intrusions and resulting crashes, fatalities, and injuries; and

2.  Develop tools to estimate the likelihood of work zone intrusions to improve work zone safety management and decision-making based on predictive models and methods.

TASKS

PHASE I—Planning

Task 1. Conduct a literature review of state-of-practice research on work zone intrusions; prediction models; and existing countermeasures including prevention and mitigation strategies. The review shall include published and unpublished research conducted through the NCHRP; FHWA; and other national, international, state, and pooled-fund sponsored research.

Task 2. Survey stakeholders, including state agencies and contractors, to identify characteristics of and concerns regarding work zone intrusions. This survey should include the data collection methods and technologies used, as well as the intrusion factors that are collected.

Task 3. Determine the data required to better understand work zone intrusion frequency and characteristics.

Task 4. Synthesize the results of Tasks 1 through 3 to identify the knowledge gaps related to work zone intrusions; prediction models; prevention and mitigation strategies and technologies; and data availability and quality. These gaps should be addressed in the final product or the recommended future research, as budget permits. 

Task 5. Propose a methodology to achieve the research objective, to be fully developed in Phase II. At a minimum, the research methodology shall:

• Include data collection plan, sample size, data specifications, and a prioritized set of work zone intrusion scenarios for testing based on the results of Phase I. Scenarios proposed should consider different work zone durations as defined in the FHWA Manual on Uniform Traffic Control Devices (MUTCD);
• Conduct an assessment of current work zone intrusion prediction models and identify the data and scenarios commonly defined in the state-of-art (e.g., interstate/local, speed, traffic volume);
• Develop predictive models and methods to estimate intrusion likelihood as a function of key roadway, traffic, and work zone variables; and
• Develop decision-support tool(s) in Microsoft Excel or similar software to aid in implementing the predictive models and methods. Include a brief instruction manual for users of the tool(s) example scenarios and limitations of use.

Task 6. Propose a preliminary outline for the proposed guide and a description of the proposed tools to achieve the research objective.

Task 7. Prepare Interim Report No. 1 that documents Tasks 1 through 6, includes the data archiving and sharing plan (see Special Note B), and provides an updated work plan for the remainder of the research. This report must be submitted to NCHRP no later than 6 months after contract execution. The updated work plan must describe the process and rationale for the work proposed for Phases II and III.

PHASE II—Data Collection and Methodology Development

Task 8. Collect and analyze data on work zone intrusion frequency and characteristics and resulting crashes, fatalities, and injuries at a sampling of work zones nationally, according to approved Interim Report No. 1.

Task 9. Execute the proposed methodology according to the approved Interim Report No.1.

Task 10. Prepare an annotated description of each section and subsection of the proposed guide.

Task 11. Prepare Interim Report No. 2 that documents the results of Tasks 8 through 10 and provides an updated work plan for the remainder of the project. This report is due no later than 15 months after approval of Phase I. The updated plan must describe the work proposed for Phase III.

PHASE III—Development of Final Products

Task 12. Develop the draft guide according to the approved Interim Report No. 2. Submit the draft guide for NCHRP approval no later than 3 months after approval of Phase II.

Task 13. After NCHRP approval of the draft guide and tools, plan and conduct a workshop with 15 representatives of owners and other stakeholders to review the draft guide and tools. Revise the draft guide, tools, and workshop materials taking into account feedback gathered during the workshop no later than 6 months after approval of Phase II.

Task 14.  Prepare final deliverables including:

1.  A conduct of research report that documents the entire research effort;

2.  The guide and tool(s) for decision-makers for use in estimating work zone intrusion likelihood;

3.  A PowerPoint presentation including speaker notes covering efforts conducted under this project suitable for conference presentation and posting on the project website; and

4.  A technical memorandum “Implementation of Research Findings and Products” as a standalone document.

STATUS: Active.