Current through Register Vol. 54, No. 45, November 9, 2024
Section 212.405 - Regulatory speed limits(a)General. Regulatory speed limits in temporary traffic-control zones and in the area in advance of a work zone where traffic queues are anticipated may be established as follows:(1) A regulatory speed limit up to 10 miles per hour below the normal speed limit may be established without an engineering and traffic study, provided the reduced regulatory speed limit is at least 25 miles per hour. Regulatory speed limits less than 25 miles per hour or more than 10 miles per hour below the normal speed limit require an engineering and traffic study and the prior approval of the Department for State-designated highways and approval of local authorities for local highways. To qualify for an additional speed limit reduction, the engineering and traffic study must indicate that traffic queues, erratic maneuvers, high vehicle crash rates or undesirable working conditions exist on the project or have existed on similar projects.(2) Regulatory speed limits for temporary traffic control must be signed with either Speed Limit Signs (R2-1), Work Area Speed Limit Signs (R2-2-2) or variable speed limit signs. For speed limits that are 50 miles per hour or less, the signs must be spaced not greater than 1/2 mile apart throughout the limits of the reduced speed limit zone. Conflicting regulatory or warning signs must be removed, covered, folded or turned so that they are not readable or identifiable by oncoming traffic whenever the reduced regulatory speed limit is in effect.(3) A Speed Limit Sign (R2-1) showing the speed limit on the section of highway immediately after the work zone must be positioned at the end of the reduced regulatory speed limit, except an R2-1 sign is not necessary if a Work Area Speed Limit Sign (R2-2-2) is used and an End Road Work Sign (G20-2) or End Work Area Sign (G20-3) is in place at the end of the regulatory speed limit.(b)Variable speed limits. In an effort to avoid unnecessary speed restrictions, variable speed limits are encouraged in lieu of static signs. These speed limits may be remotely controlled, either manually or by a computer using hardware and software to monitor functions such as traffic speeds, volumes, densities and queues.