State Safety Initiative Database

Explore relevant case studies by filtering via agency, keyword, or pre-set filters in the left menu, or by using the topic tags located at the bottom of the page.

Analysis of the Safety Effectiveness of Rear-End Collision Avoidance ADAS

FHWA
This study analyzed the safety effectiveness of FCW (forward collision warning) and CIB (crash imminent braking) ADAS (advanced driver assistance systems) systems based on large-scale, police-reported crash data combined with decoded VINs of crash vehicles. The QIE and logistic regression were adopted to measure and compare the reduction of rear-end striking across driver and vehicle groups.

Automated Work Zone Speed Control (AWZSC) Program

Connecticut
The state of Connecticut has witnessed a rise in work zone crashes. In 2021, legislation was passed in Connecticut to allow a Pilot program for speed safety cameras in work zones. The Pilot demonstrated that this technology was highly effective at slowing drivers in work zones and led to the passage of a bill in 2024 that authorized the Connecticut Department of Transportation (CTDOT) to operate these in up to 15 highway work zones at a time on a permanent basis. CTDOT began operation in the 2026 construction season of a permanent Program that deploys specialty equipment to detect speeding vehicles, record data and images of the vehicle license plates, and then issue warnings for first time violations, and subsequent infractions for repeat violations. The Program also developed a robust education campaign to support the roadside enforcement equipment. Some of the approaches include an AWZSC-branded fleet of SUVs for both mobile and stationary units, as well as a comprehensive social media campaign. The campaign stressed that the Program is not a profit-driven initiative but a people-focused initiative because our workers' lives matter as much as our residents' or anyone else's.

Roundabout Screening Study – Seeking Good Locations for Crash Reduction

Connecticut
A roundabout intersection screening study was performed by the Capitol Region Council of Governments for the 38 communities in the Hartford, Connecticut region. The study identified locations likely to result in significant reduction of fatal and serious crashes if converted to a single lane roundabout.

Fighting Impaired Driving on Every Front

Connecticut
Connecticut is fighting impaired driving on every front. Our poster highlights the state's innovative, nationally recognized approach-from toxicology testing and Drug Recognition Experts to phlebotomy programs, legal enforcement, and public education-all in an effort to save lives and make our roads safer.

Enhancing Road Safety through Context Classification

Connecticut
CTDOT has recently developed a Context Classification System to support its Complete Streets Policy and advance context-based planning and design. By aligning roadway design with the surrounding environment, the system supports the Safe System Approach and promotes safer travel for all road users.

Deployment and Safety Evaluation of Variable Speed Limits on I-70

Colorado
Deployment and evaluation of a Variable Speed Limit (VSL) algorithm on I-70 in Colorado. The flow-, weather-, queue-, and transition-based algorithm adjusts speeds in real time. An Empirical Bayes before-after evaluation found approximately 30% reductions in crash frequency and severity.

Evaluating the Effect of Stop Bar Setbacks at Signalized Intersections

Colorado
Signalized intersections with stop bars set back 40 to 50 ft. from conflicting traffic, depending on posted speed, had substantially fewer broadside crashes. U.S. and Australian data analyzed using Broadside Safety Performance Functions and network screening indicated 40 to 50% reductions.

Arizona Virtuous Cycle of Safety – Traffic Data to RSA to Design Changes

Arizona
ADOT uses a continuous feedback loop in traffic safety. Crash and driver behavior monitoring develop road safety audit (RSA) candidate locations. RSAs develop recommended design changes. Approved recommendations are designed into roadway projects. New designs are then monitored for crash and driver behavior. Full circle.