Welcome to the forum. You did not say which state/municipality where your project is located, and that is critical. Your requirements may vary significantly, based on which code was adopted by the Authority having Jurisdiction (AHJ).
Please also be advised that there may be additional regulations that are applicable to your project that may not actually be enforced by the AHJ.
For example, I'm working on an affordable multifamily housing project in Los Angeles that uses federal tax credits and city dollars:
- California has its own accessibility code, CBC 11B, which is enforced by the building department. It requires 5% of the dwelling units to be mobility accessible, and the remainder to be adaptable. Commercial bathrooms must meet ADA.
- the Fair housing Act (FHA) has federal requirements to make dwelling units adaptable.
- Publicly funded housing is subject to compliance with the Americans with Disabilities Act. no one plan checks for this: you are expected to know it, and you might get sued for discrimination if you fail to comply. 5% of my dwelling units and all of my common area amenities (including commercial bathrooms) must be mobility accessible.
- Tax credits are considered a form of Federal funding / subsidy, which triggers compliance with federal section 504 and the Uniform Federal Accessibility Standards. UFAS has some areas that are more stringent than ADA (example: % of accessible washers and dryers).
- In California our tax credit committee has requested that 10% of the units must be mobility accessible.
- the city of LA requests that when they fund housing projects, 15% or more of the units should be mobility accessible.
After all this, you then need to comply with whichever specific requirements are the most stringent. In ADA, an accessible bathroom sink must be at least 15" away from an adjacent side wall; in California, it's 18" min. We design to 18".
So when you ask for "requirements and code" for commercial bathrooms, your location and funding sources need to be the starting point.