From January 2017 until December 2017 The Cowra Guardian reported on 18 instances were drivers were found guilty of mid range drink-driving and could have been ordered to install an interlock.

The mandatory alcohol interlock program will be expanded under the new Road Safety Plan to include all mid-range drink-driving offenders.

Interlock device installation, monthly device leasing, regular device servicing and device removal at the end of the mandatory interlock period can cost the offender about $2200 a year.

Cowra Auto Electrical currently install the devices with owner Brian McCabe saying they installed quite a few of the devices last year with banned drivers coming from as far as Canberra for installations.

Drivers ordered to install an interlock device under current rules have limited access to installers.

There are three accredited interlock service providers in NSW, Guardian Interlock Systems, Draeger Safety Pacific and Smart Start Interlocks.

Outside of Cowra installers in the region are based in Bathurst, Dubbo, Parkes, Wagga and Forbes.

Interlocks are electronic breath testing devices linked to the ignition system of cars, motorcycles and heavy vehicles.

Drivers must provide a breath sample that the interlock analyses for the presence of alcohol.

It prevents the vehicle from starting if alcohol is detected. Randomly timed breath tests must also be passed while you drive.

All breath test results, a photograph of the person providing the sample, and any attempts to tamper with the device are recorded by the interlock.

This information is used to monitor attempts to drink and drive, and any breach of interlock licence conditions.

In NSW, all program participants must have a zero blood alcohol concentration when driving.