Intelligent Speed Assistance Reduced Time Spent Driving Over Speed Limits by 64.18 Percent in New York City.
New York City Pilot Study Tested the Effects of Deploying Municipal Fleet Vehicles Equipped With Intelligent Speed Assistance.
New York City, New York, United States
New York City Intelligent Speed Assistance Pilot Evaluation
Summary Information
New York City has the largest municipal fleet in the United States with more than 28,700 vehicles. To comply with the objectives set by various municipal plans such as the New York City Safety Fleet Transition Plan, this pilot study aimed to test the effectiveness of intelligent speed assistance (ISA) in reducing dangerous speeding in a public sector fleet. ISA is an in-vehicle technology designed to help drivers comply with speed limits by preventing vehicles from exceeding posted speed thresholds. When a driver attempts to exceed the speed limit, the ISA system intervenes to restrict acceleration, thereby enhancing road safety. The pilot study deployed 400 ISA-equipped vehicles across 16 city agencies and New York City School Bus Umbrella Services (NYCSBUS) between 2022 and 2024 to explore the safety benefits of this technology.
METHODOLOGY
The pilot study includes 670 total fleet vehicles consisting of 400 ISA-enabled ones, and 270 control vehicles. The ISA devices on the 400 treatment vehicles were active between July 13th, 2022, and February 16th, 2024. The test vehicles were separated into two cohorts, with 540 of control and treatment vehicles being the primary cohort, and the rest 130 being the habitual speeder group. This primary cohort included 440 vehicles (evenly split between control and treatment) across 16 city agencies, and 100 school buses operated by NYCSBUS. The study matched the vehicle year, make, and model, and utilizing agency as closely as possible between the control and treatment vehicles. The study recorded near-real-time location and speed data for participating vehicles before and after ISA implementation. The location, instantaneous speed, and posted speed limit data for the 60-day pre-/post-ISA periods were extracted for each vehicle.
FINDINGS
The main findings from the study were as follows:
- The primary cohort had a 64.18 percent reduction in the time driven over 11 miles per hour (MPH) over the posted speed among ISA-equipped vehicles, while the control vehicles had a 9.71 increase in time spent driving over speed limit after the pilot period.
- The habitual speeding cohort also showed a 49.22 percent reduction in driving over speed limit after ISA implementation.
- Overall, speeding drive time reduction ranged from around 50 percent on local roads with 25 MPH speed limit, which had speed safety cameras set to the same enforced speed threshold, to 82 percent reduction on roads with 50 MPH speed limit.
