US auto-safety regulators said on Tuesday they have begun the process that will eventually force carmakers to adopt new technology to prevent intoxicated drivers from starting vehicles.

In 2021, Congress directed the National Highway Traffic Safety Administration (NHTSA) to mandate a passive technology to try to avert more than 10,000 road deaths annually. The law requires a technology safety standard by November 2024 if the technology is ready.

A number of technologies currently under development could potentially prevent impaired people from starting a vehicle, including breath- or touch-based sensors to detect alcohol. Another potential option is using cameras to monitor eye movements to try to determine whether drivers are intoxicated.

Still, NHTSA must be assured the technology works before it can require it, and then give automakers at least three years to implement it once it finalizes rules.

“We are trying to see, can we get it done, does the technology exist in a way that is going to work every time,” said Ann Carlson, the acting NHTSA administrator , adding that public acceptance of the technology would depend on its accuracy.

Carlson said there were close to 1bn daily driving journeys in the United States.

“If it’s [only] 99.9% accurate, you could have a million false positives,” Carlson said. “Those false positives could be somebody trying to get to the hospital for an emergency.”

The NHTSA on Tuesday published an “advance notice of proposed rulemaking” to begin the process of gathering information on how such technology could be developed and required.

Its regulatory notice details the research and technological advancements needed to finalize regulations and options for potential rules, citing “Blood alcohol content detection, impairment-detection (driver monitoring), or a combination”.

Tess Rowland, the president of Mothers Against Drunk Driving (MADD), said the group was “very pleased” with NHTSA’s launch.

“We understand we still have a mountain to climb,” Rowland said. “Victims and survivors are not going to let this die.”

In 2021, 13,384 people died in alcohol-impaired driving traffic deaths, the most recent statistics available.

Carlson will tell a US House of Representatives committee on Wednesday that US traffic deaths fell 4.5% in the first nine months of the year after sharply rising during the Covid-19 pandemic.

“While we are optimistic that we’re finally seeing a reversal of the record-high fatalities seen during the pandemic, this is not a cause for celebration,” Carlson’s written testimony says.