Residents of Montana may be aware of the rules for operating large vehicles, such as commercial trucks. Many rules are designed to reduce the number of truck accidents on highways. Owners and drivers have to abide by the rules, including speed restrictions, vehicle weight, standards on tire and braking systems and obeying the road signs.
All trucks weighing over one ton must follow the Montana speed limit law, under which the daytime speed limit on interstate highways is 65 mph, and on the primary and secondary highways, it is 60 mph. At night, the speed limit on interstate highways remains the same, but it is reduced to 55 mph on primary and secondary highways. For double and triple trucks, which are only permitted to drive on interstate highways, the speed limit for both day and night remains at 55 mph.
Trucks should be equipped with an engine compression brake device and studded tires are permitted between October and May. Chains are required on the drive wheels of the vehicles and are to be used in the zones where "chains required" signs have been erected by the department of transportation. The Traffic Department may also maintain and operate weigh stations on the highways to weigh vehicles over 10,000 pounds and to verify that they are in compliance with the law.
In case a trucker fails to comply with the rules and standards of operating a heavy commercial vehicle, the Department of Transportation is empowered to prohibit the vehicles from being used for any commercial activity. For commercial truck drivers, if it is determined that they are driving under the influence of alcohol, the permissible blood alcohol level is 0.04, whereas, for other vehicle drivers, it is 0.08. Truck drivers need to follow the traffic rules strictly and any violation may lead to a fine or prison term. It may also lead to the person's inability to find a job.