Question:
California Code seems to be the most difficult to search on the internet. I am looking for Code and Laws related specifically concerning projection rooms, i.e. building requirements such as bathrooms in booth, safety, amount of equipment per square feet, etc.

Answer: I suspect that you will have to go to a more local level than the state. Theatres are covered under the "Uniform Building Code" and most municipalities and county governments base their own permit process on this, perhaps adding local restrictions. Reaching way back into memory, I seem to recall that booths must have at least 80 SF of floor space and one ceiling ventilator, have the usual non-flammable wall treatment, wiring enclosed in conduits or chase, and sprinklered space with battery backup exit sign and emergency lighting. Two exits or more may be required based on size. Newer codes probably dictate shut-offs of equipment and HVAC based on triggering of the fire alarm, annunciator, etc. Contact the fire dept or office of the fire marshall in the area. AFAIK, bathrooms are not a requirement in booths, although they may have been when nitrate and carbons were in common use.