The introduction of alcohol interlock devices in all new vehicles in the US could prevent 85% of deaths due to alcohol related crashes, according to a new study.

In the US the equivalent of 30 people a day lose their lives in alcohol-related motor vehicle crashes. According to the Centres for Disease Control and Prevention (CDC), 10,322 people in the US were killed in alcohol-related motor vehicle crashes in 2012, accounting for more than 30% of all motor vehicle deaths.

More than 1,100 of these deaths involved children aged 14 and under, and 20% of these cases involved a driver who was under the influence of alcohol.

The majority of US states enforce the use of an alcohol interlock device, also known as an ignition interlock device, for those who are convicted of drink-driving. These devices are installed in their vehicle to prevent them from repeating the offence, in that vehicle at least.

An ignition interlock device is installed in a vehicle’s dashboard. It operates with the use of a breathalyzer that is integrated into the vehicle’s ignition system. Before starting the vehicle, the driver must breathe into the device for it to measure how many grams of alcohol are present in each decilitre (g/dl) of breath, which is an indicator of the level of alcohol currently in someone’s system. If the driver’s alcohol levels are above the legal limit – which varies from state-to-state in the US – the vehicle will not start.

Dr Patrick Carter of the University of Michigan Injury Centre and researcher in the study said: “Interlocks are highly effective while installed on the vehicle, with a systematic review finding a 67% [average] reduction in DWI (driving while intoxicated) recidivism.” – people who continue to commit the crime after being punished.

Interlock Breathalyser Device Could Save Lives

For the study, Dr. Carter and colleagues set out to estimate how many drink-driving injuries and fatalities could be prevented over the next 15 years if interlock devices were installed in all new vehicles.

Using data from the Fatality Analysis Reporting System and the National Automotive Sampling System’s General Estimates System, the team assessed the non-fatal injuries and fatalities that occurred as a result of alcohol-related motor vehicle crashes between 2006 and 2010.

From the results of the study the researchers suggest that 85% of alcohol-related motor vehicle deaths and up to 88% of non-fatal injuries in the US could be prevented over a 15-year period through the installation of interlock devices in all new vehicles. This would equate to 59,554 lives saved and around 1.25 million non-fatal alcohol-related vehicle crashes prevented, according to the researchers.

They also estimate that it would save around $343 billion in unintentional injury costs. It would cost around $400 to install each device, but the savings to society would outweigh the cost of device installation within 3 years, according to the researchers.

Interlock Breathalyser Device – Potential and Limitations

Dr Carter told Medical News Today: “We knew our modelling would yield significant results, but the sheer numbers of preventable fatalities and serious injuries were surprising. Our analysis clearly demonstrates the significant public health benefit and societal cost savings associated with including alcohol ignition interlock devices as standard equipment in all new cars.”

The most positive estimations of this system may be down to the alcohol-limit settings of the devices themselves. These estimates have been based on devices of that are set to 0.02 g/dl, when some devices are currently set up to 0.04 g/dl.

Dr Carter added: “While the standard use of alcohol interlocks in all new vehicles is one solution for the prevention of drinking and driving, policy makers, car manufacturers and the public will need to best determine how such technology can best be optimally deployed.” Although there are a number of factors that may influence the success of its implementation, Dr. Carter suggests there is great potential for the system saying: “Our research does demonstrate the potential opportunity for injury prevention and cost savings with widespread use throughout all vehicles.”