Maryland DUI/DWI Interlock Providers
The device is basically an option following a DUI/DWI arrest in Maryland when a breath sample is provided reflecting a BAC (breath alcohol content) of .15 or higher or when the driver refuses to blow when requested to by a police officer.
The following locations are certified by Maryland's MVA:
Nat'l Interlock Service - 800-374-5760
Smart Start - 800-880-3394
Draeger Interlock of Maryland - 800-332-6858
Guardian Interlock Systems - 800-499-0994
Alcohol Detection Systems - 800-786-7394
The foregoing companies offer different products at different prices. They may also charge differently for their prodcurts. In this writer's experience, digital devices tend to be more accurate then analog devices where you have a choice.