Volvo is offering a tool to help drivers realize when they are too drunk to drive.
Its Alcoguard device tests alcohol levels in drivers and will be available as an option on its 2008 Volvo S80, V70 and XC70 models in Sweden, the U.S. and Europe.
The Alcoguard is a handheld device that wirelessly integrates with the car to prevent drivers over the legal alcohol limit from starting it up. Volvo refers to the device, which must be used within 10 meters (about 33 feet) of the car, as an "alcolock."
Drivers must blow into the device, which is powered by fuel-cell technology, before the car with an alcolock can be started.
"Unlike semiconductors, for instance, fuel cells only react to ethanol and nothing else. In the fuel cell, the ethanol molecules pass through a sensitive membrane and an electrical current is generated. This current is then measured. Higher current means more alcohol in the driver's breath," David Nilsson, technical project manager for Alcoguard at Volvo Cars, said in a statement.
Test results showing more than a 0.2 g/l alcohol level (the Swedish limit) are indicated with a red LED light and the car's engine will not start. The car will start with results below 0.1 g/l alcohol indicated by a green LED and between 0.1 - 0.2 g/l indicated with a yellow LED. The tool can be adjusted by Volvo to meet the blood alcohol limits of specific countries.
Results are stored for up to 30 minutes so drivers don't have to keep retesting every time they turn off the car and then get back in again within a short time span as they would while running errands.
The obvious question is whether drivers can cheat the device. While a drunk driver could theoretically have someone else start the car for them, this would necessitate a sober person enabling the drunk person to drive. A drunk person alone would not be able to get around the system.
"Thanks to advanced sensors, it is not possible to use external air sources such as a pump to cheat the system," said Volvo in a statement.
The feature will be of specific value to fleet-based cars used by companies, municipalities, police forces and taxi services, said Volvo in a statement. It plans to add the tool as an option to its other models by summer 2008.
Nissan announced similar DUI-technology in July 2007.