Speed Zoning is the practice of establishing speed limits that are reasonable and safe for specific sections of the roadway. The public mistakenly associate higher speed with more accidents, but data does not support this theory. Speed Zoning is a traffic engineering tool that can properly enhance traffic safety. Many studies have shown that lowering speed limits artificially can reduce the speed limit’s effectiveness and promote a culture where speed limits are totally ignored.

Speed Zoning requires the implementation of civil engineering and with a speed or traffic survey. Through a combination of measuring traffic speeds, and inventory of crash records, and road conditions the critical speed is set at the 85th percentile of the volume of traffic moving through an area establishes a proper speed limit.

AAA of California has published the following book that explains the practice of Speed Zoning based on the California Vehicle Code (CVC) and the California Manual on Uniform Traffic Control Devices (CA MUTCD), as a way to educate the public on how safe speed limits are determined.

Effective Speed Zoning