New rules allowing for a maximum speed limit of 80 mph in rural, less populated areas were approved last week by the Texas Transportation Commission.

The rules, which do not include tractor-trailers, implement the Legislature’s House Bill 2257, which allows 5-mph speed limit increases on interstate highways in counties with populations of less than 15 persons per square mile. New speed limit signs were unveiled this past weekend in time for Memorial Day travel.

Factors evaluated during speed limit engineering studies included prevailing speeds -- logged between 77-and-79 miles per hour for 85 percent of drivers -- roadway width, crash history, horizontal or vertical curves, and shoulder conditions.

The truck speed limit will remain at 70 miles per hour.