The Americans with Disabilities Act is governed by the federal government. The 1991 ADA standards for Accessible Design is approved and published by the Department of Justice. All subsequent updates are approved and adopted through the Department of Justice. The adopted updates are published and available on the ADA website. (See Resources.)
In 2006, the model building codes that were adopted by each individual state were combined and rewritten as the International Building Code. The International Building Code, like the model codes before them, adopted and incorporated the Americans with Disabilites Act standards for Accessible Design. The International Building Code follows the regulations described in the Accessible Design manual. The Accessible Design manual provides standards and minimum requirements that designers and engineers must follow in order to comply with the Americans with Disabilities Act.
The California adopted the International Building Code as it's model code to for writing the state's California Building Code. California is one of the few states that has adopted stricter requirements for ADA compliance in its building code. One example is California's requirements for Braille. The state created what is known as "California Braille" in 1980, which exceeds the minimum requirements called for in the Americans with Disabilities Act.
Each local city jurisdiction has to adopt the state's building codes. The local city building codes can have stricter requirements for ADA compliance then what is asked for in the state's building codes or even in the Americans with Disabilities Act. Each local jurisdiction will any additional ADA specifications written and adopted by the governing city council before it can be enforceable. The local city planning and bulding department will have all the requirements in their offices for individuals to read.