Road to Zero has been issuing recommendations for vehicle-based approaches to preventing dangerous speeding, focusing on ISA, since 2023. That’s the same year National Transportation Safety Board advised that ISA should be included in new passenger vehicles. Meanwhile, in the European Union, new vehicles are now required to come equipped with at least passive ISA. It makes sense: ISA targets one of the most common factors in fatal crashes, and, in the case of active systems, it actually prevents the driver taking a dangerous action. The result of this layer of redundancy, and mitigation of human error, is safer speeds, a component of a Safe System. If ISA were widely implemented in both new vehicles and as an after-market intervention on older models, it could potentially prevent thousands of deaths and serious injuries in the United States.

There is proof that ISA works: New York City’s municipal fleet has undertaken the nation’s largest pilot of this technology, installing it in 500 vehicles across all weight classes and uses. An October 2024 evaluation in conjunction with the USDOT Volpe Center found that this centrally controlled active ISA reduced speeding incidences by 64 percent. It was even effective in vehicles driven by employees who had been identified as “high risk” due to past habitual speeding. Similar government fleet pilots are taking place in Ventura County, California; Somerville, Massachusetts; and King County, Washington. Because such a large proportion of crashes involve speeding, installing ISA in fleet vehicles may lower overall costs by preventing expensive repairs and payouts.

In Washington, DC, a new law, the STEER Act, requires installation of ISA devices in the vehicles of drivers convicted of serious speeding offenses, similar to ignition interlock programs that follow convictions for driving while intoxicated. This law went into effect on Oct. 1, 2024.

ISA Myths vs Reality

MYTH: ISA will make vehicles inefficient

The truth is that speeding really doesn’t save much time, even over a long distance, but it does burn substantially more fuel.

MYTH: Installing ISA onto a large number of vehicles is prohibitively expensive

In the New York City fleet pilot, ISA systems cost $1,500 per vehicle to install. This may actually save money in the long term by reducing expensive crashes, especially those which result in injuries or deaths.

MYTH: In emergency situations, it’s crucial to be able to go faster than the speed limit

Most active ISA systems do have some type of temporary emergency override for use in exceptional situations. But the vast majority of journeys have no good reason to exceed the speed limit, which is the law.

MYTH: Crashes aren’t just about speeding. There are other factors in play.

Yes! Safe speed is a component of the Safe System Approach and others must be considered as well. However, excessive speed is a factor in about one-third of road deaths in the United States. Furthermore, speeding can compound the impacts of other dangerous driving decisions, such as driving while impaired by alcohol or drugs, as was the case in the Nevada crash that killed nine people and led the NTSB to recommend ISA as standard. Furthermore, larger size and greater weight of vehicles makes a higher-speed crash more likely to kill. So none of these aspects can be ignored, and addressing safer speeds is crucial to getting to zero deaths.

Join Road to Zero as we continue to pursue the technology that truly works to save lives. We are your source for evidence-based best practices, and we bring together organizations from all over the country that are dedicated to eliminating preventable road deaths.