Volvo Buses


Volvo to launch bus-adapted alcolock system

The new alcolock system from Volvo Buses is specifically adapted for the bus industry’s requirement for rapid driver changes on route. The vehicle can be started without a breath test, but the brakes will remain locked if the driver is not sober.

An increasing number of bus companies are choosing to increase passenger safety by introducing the alcolock system in their buses. The alcolock is a control system that prevents the driver from driving while under the influence of alcohol since a breath test must be taken before starting the bus. If the driver is under the influence of alcohol or does not perform the test, the bus will not operate. The upper limit for alcohol concentration in the blood is 0.2.

Volvo held the first demonstration of its alcolock system for heavy vehicles in 2007. The unit prevented drivers from starting the engine while under the influence of alcohol. 

“It is an ignition interlock device, which means that before the engine can be started, the driver first has to exhale into the device and the breath alcohol concentration can be analyzed,” says Jan-Olov Åkersten, Safety Manager at Volvo Buses.

“It is a perfect solution for truck or coach operators, but if you have a big fleet of city buses, it’s a different thing. This is why Volvo Buses developed an alcolock system of its own.”

Time saving
City bus line schedules often mean that drivers begin or finish their workday at a bus stop, instead of at the bus depot. To keep the schedule, it is necessary to make the change of driver as quick as possible.

“With the previous alcolock system, the driver who was finishing a shift had to shut down the engine for 15 minutes to reset the alcolock system,” explains Jan-Olov Åkersten. “The new driver then logged on, took the breath test and, after a negative result, was able to start the engine.”

With the new Volvo alcolock solution, there is no need to turn off the engine, as the brakes instead block the bus, saving valuable time. Now, the driver firstly resets the system with a button, but allows the engine to run. The brakes are simultaneously activated. The second driver performs the breath test and is then able to continue the journey.

“There is another major advantage for operators with large bus fleets,” says Jan-Olov Åkersten.

Preparing and warming up a bus fleet in the depot in the morning can be a one-man job. Having to first perform 30 breath tests to be able to start 30 buses takes a long time. But now, there is no need for the breath test until the driver comes to collect the bus.

The system is also adapted for workshops. There is a workshop mode, which means that the bus can be driven in the depot at a maximum speed of 15 km/hour with hazard flashers, without first performing a breath test. 

Dashboard display
Volvo Buses’ alcolock system consists of a handheld unit connected to the dashboard display. The display is located where all other information about the bus is shown and the driver can see the test results immediately without needing to remove the handheld unit from his/her mouth.

The handheld unit is not connected to a certain vehicle and can thus be collected from the buses and calibrated at one of Volvo Buses’ service centers, which means that calibrating large bus fleets is simple.

“The new alcolock system is available for buses with the BEA 2 electrical system, which means most bus models manufactured in the past four years,” says Jan-Olov Åkersten. “The system is simple to install as an aftermarket accessory or on the assembly line.”

October 07, 2009

For further information, please contact Per-Martin Johansson, Press Officer, +46 31 322 52 00, E-mail: