California is far from alone in its adoption (or adaptation) of the FGI Guidelines per the illustration below. And I'll note that as much as FGI strives to keep this material updated and correct, this is always a moving target, and even my home state of Ohio isn't shown truly correctly. (It's never been formally adopted in Ohio, but, de facto, we use the most recent version used by CMS and TJC.)
More pointedly to your question, California, to my knowledge, develops its own document, which, in turn, uses the Guidelines as a basis.
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Peter Bardwell FAIA Member Emeritus
BARDWELL+associates, LLC
Columbus OH
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