Safety and Operational Impacts of Differential Speed Limits on Two-Lane Rural Highways in Montana

  title={Safety and Operational Impacts of Differential Speed Limits on Two-Lane Rural Highways in Montana},
  author={Timothy J. Gates and Peter Tarmo Savolainen and Brendan J. Russo and Raha Hamzeie and Jonathan Kay and Sterling Frazier and Jacobo Finkelman},
As of July 2016, Montana was the only state to maintain a differential speed limit on two-lane two-way rural highways, utilizing a daytime statutory speed limit of 70 mph for cars and light trucks and 60 mph for trucks exceeding a one-ton payload capacity. Although differential speed limits are common on freeways, the use of differential limits on two-lane roadways presents unique safety and operational issues due to passing limitations and subsequent queuing, and prior research on such issues… 

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