California Manual on Uniform Traffic Control Devices

Design specifications are detailed on a section of the Caltrans website that is based on the national Standard Highway Signs and Markings (SHSM) document.

In 1952, the California Department of Public Works Division of Highways published a Planning Manual of Instructions.

Section 21401 legally requires all traffic control devices on streets and highways to conform to these standards.

[5] The CA MUTCD is developed by Caltrans in consultation with the California Traffic Control Devices Committee (CTCDC) and other stakeholder agencies.

The CTCDC is the successor to the California State Sign Committee, which was originally responsible for highway signage from 1933 to 1947.

Each of the California sign specifications is assigned an alphanumeric designation and organized according to the same series found in the SHSM.

California is the only state that retains the nonrectangular U.S. Route shield , which was used nationally until 1961.
The iconic " immigration sign " was coded as W54 in the 1990s.
In California, guide signs are laid out horizontally with a consistent height. Pull-through signs are used instead of diagrammatic signs . [ 7 ]