Crash Modification Factors for Automated Traffic Signal Performance Measures (2026)
Chapter: 8 Conducted Webinars
CHAPTER 8
Conducted Webinars
The research team conducted two online webinars with state DOT representatives. The objective of the webinars was to disseminate the research findings and to gather feedback on the research results. The content of each webinar was the same; it was offered twice to accommodate the participants’ varied availability. The webinars were scheduled for 90 minutes. Their agenda is provided in the following list.
- Introductions (5 minutes)
- Project overview/objectives (5 minutes)
- Data collection and methodology (10 minutes)
- Key findings (20 minutes)
- CMFs
- Benefit-cost analysis
- Application spreadsheet demo (30 minutes)
- Discussion and questions (20 minutes)
The next section provides a list of the webinar participants. The last section provides a summary of their comments.
Webinar Participants
The first webinar was conducted virtually on May 1, 2025. Twenty-nine attendees (excluding the research team members, Panel members, and NCHRP staff) participated in the webinar. Column 3 of Table 59 shows the number of agencies and consultants who participated in the first webinar, along with the number of staff from each agency.
The second webinar was conducted virtually on May 7, 2025. Twenty attendees (excluding the research team members, Panel members, and NCHRP staff) participated in the webinar. The last column of Table 59 shows the number of agencies and consultants who participated in the webinar along with the number of staff from each agency.
All total, 24 state DOTs were represented at the webinar series.
Table 59. List of state DOTs and agencies that participated in a webinar.
| Agency Category | Agency | Number of Participating Staff | |
|---|---|---|---|
| Webinar 1 | Webinar 2 | ||
| State DOT | Alaska DOT | 1 | 1 |
| Arizona DOT | 1 | 1 | |
| Arkansas DOT | 2 | - | |
| Connecticut DOT | - | 1 | |
| Delaware DOT | 3 | 1 | |
| District of Columbia | 2 | - | |
| Iowa DOT | - | 1 | |
| Kansas DOT (represented by Burns & McDonnell) | 1 | - | |
| Maryland DOT | 1 | 1 | |
| Massachusetts DOT | 4 | - | |
| Michigan DOT | 1 | 2 | |
| Minnesota DOT | - | 1 | |
| Mississippi DOT | - | 1 | |
| New Jersey DOT | 1 | 1 | |
| New Mexico DOT | 1 | 1 | |
| North Carolina DOT | 1 | - | |
| Ohio DOT | 1 | - | |
| Oregon DOT | 2 | 2 | |
| Pennsylvania DOT | 1 | 1 | |
| South Carolina DOT | - | 1 | |
| Tennessee DOT | 2 | 1 | |
| Texas DOT | 1 | 2 | |
| Virginia DOT | 1 | - | |
| Wyoming DOT | 1 | 1 | |
| Other | FHWA | 1 | - |
| Total: | 29 | 20 | |
Summary of Comments
Questions and comments were taken during (and at the end of) each webinar. Most of the questions can be characterized as requests for clarification or additional information about the underlying research.
Two comments were offered. One comment was with regard to the wide site-to-site variation in the case A CMFs. It was observed that this variation did not lend itself to generalization about the predicted safety effect of ATSPM deployment at future locations, especially in states other than those studied. The commentor inquired as to what guidance might be provided in the research products to guide analysts interested in assessing the safety benefit of ATSPM deployment at a specific signal system.
In response to the aforementioned comment, the presenters pointed out that the ATSPM Evaluation Methodology guidebook does provide some guidance in this regard. Specifically, Step 2 of the methodology discusses the various signal operation features that can affect safety outcomes when monitoring and maintaining a signal system using ATSPMs. It encourages the analyst to consider these features, as well as case A CMFs developed for Project 17-109, when determining the appropriate CMF value for their
proposed signal system. The guidebook also directs the analyst to a section of the guidebook (i.e., Section 2.5) wherein the documented safety effects of a range of signal system features have been synthesized.
A second comment was with regard to the indirect safety benefits that can be obtained from the use of ATSPMs to monitor signal operation. These indirect benefits may not be adequately captured using case A or B CMFs developed for Project 17-109. The commentor noted that ATSPMs can be used to identify dysfunctional signal system components (e.g., detectors) much more quickly than with traditional signal system management. This feature has the potential to reduce the duration of time that the system is operating in a suboptimal manner, which can often have a safety benefit. The commentor also noted that monitoring of ATSPMs can flag intersections that are having operational problems (e.g., congestion, inadequate capacity) that could lead to frequent conflicts and possible crashes. This information has the potential to trigger action by the system managers to mitigate the operation problems and, thereby, reduce or eliminate related conflicts and crashes.
In response to the aforementioned comment, the research team indicated that they would include in the project final report some discussion of the potential for ATSPM deployment to have indirect safety benefits that may not be fully quantified by the case A and case B CMFs. The discussion would include examples (such as those noted by the commentor) of how the use of ATSPMs to monitor signal system performance is likely to have a safety benefit.
