Waymo has put out a new safety report, complete with not only relevant information about how its self-driving vehicles are coming along but also important things like how they interact with first responders if the need to do so arises. According to the document, Waymo's vehicles include powerful audio sensors that can detect sirens. Once a siren or other emergency signal is detected, Waymo's cars can react according to other stimuli to do things like pull over for a police car, yield to an ambulance, or pull to the side of the road for a passing fire truck, for example. The goal, like any other safety measure implemented in Waymo's self-driving car systems, is to encourage safety and uniformity by following applicable traffic laws in the same way that a human driver would.
Waymo, according to the report, has briefed police departments and other emergency response teams in all of the cities where it's currently testing its self-driving cars. In Arizona, Waymo actually got the Chandler police department to help it train its vehicles by trailing, passing, and leading them, among other actions, to teach them how to recognize not only an emergency vehicle itself, but what the proper procedure is for each of the various things an emergency vehicle may do on the road as it nears the car. On top of this specialized training, of course, Waymo's fleet is learning organically as emergencies happen in the cities encompassed by its pilot program.
One sticky situation that could arise is a self-driving car being pulled over for one reason or another. While the vehicles are programmed to follow traffic laws to the letter and stop for help at the first sign of any hardware or software issues, police cars may have their reasons to pull over Waymo vehicles. When that happens, the vehicle itself following procedure and pulling over will only be part of the issue at hand; exactly what happens when a Waymo car does manage to commit an infraction or get in a crash is still widely debated. Waymo is training first responders on a city-by-city basis on how to interact with its vehicles, but once they deploy nationwide, wider procedures may need to be in place, likely even at a federal level.