Think you’re smart enough to fool the cops if you get pulled over for weaving on the way home from a party? Or to lie to your mother about whether you’ve been drinking? Your car knows the truth.
Or at least it would with new technology on display in Washington, D.C. The National Highway Traffic Safety Administration (NHTSA) unveiled a prototype vehicle with an advanced alcohol detection system that could ultimately prevent vehicles from being operated by a drunken driver.
The Driver Alcohol Detection System for Safety — known as “DADSS” — is a noninvasive system aimed at detecting when a driver is above the legal alcohol limit by instantly measuring the driver’s breath or skin. If your blood alcohol level is above 0.08 percent — the legal limit in all 50 states — the car will be disabled.
The federal government is developing the system in partnership with major automakers and their suppliers. Here’s how it would work:
In the breath-based system, being developed by Sweden’s Autoliv Development, the driver’s natural exhaled breath is drawn into a sensor on the steering wheel, which uses infrared light beams to measure the concentrations of alcohol and carbon dioxide present. (Molecules of alcohol and carbon dioxide absorb infrared radiation at specific wavelengths, so the system can quickly tell the difference between the two and accurately calculate the alcohol concentration.) It’s less intrusive than today’s in-car breathalyzers, which require some convicted drunken drivers to blow into a tube before they can start their car.
In the touch-based system, blood alcohol levels under the skin’s surface are measured by shining an infrared light through the fingertip. It will be integrated into the start button or steering wheel, and take multiple, accurate readings in less than a second. It’s being co-developed by Takata, a major automotive supplier, and TruTouch, an expert in alcohol sensing using near-infrared spectroscopy.
The systems, still about five years away, would be offered as optional equipment on future vehicles for about $400. For now, there’s no effort to make them mandatory.
“There is still a great deal of work to do, but support from Congress and industry has helped us achieve key research and development milestones,” NHTSA Administrator Mark Rosekind said. “DADSS has enormous potential to prevent drunk driving in specific populations, such as teen drivers and commercial fleets, and making it an option available to vehicle owners would provide a powerful new tool in the battle against drunk driving deaths.”
The big question, of course: does it work? The American Beverage Institute, a restaurant trade group which opposes the technology, said it can take a couple of hours for a person to reach peak blood alcohol content after he or she stops drinking. This means that you could have five drinks and still have a blood alcohol concentration level below 0.08 when you started your car. As a result, the group figures the threshold for disabling the car would have to be set artificially low to head off these potentially unsafe drivers.
“‘Voluntary’ passive alcohol sensors like DADSS will do nothing to keep these dangerous drivers off our roads. Instead, DADSS will simply stop many responsible social drinkers who have a glass of wine with dinner from starting their cars,” ABI Managing Director Sarah Longwell said.
Other potential issues involve false readings. Could the system be triggered for instance, if the driver just wiped his or her hands with Purell? The system needs to be instantaneous and foolproof, which is why it’s still under development.
This article originally appeared on Forbes.
