toilet clearance

Hi All, I'm in Utah, and it's my understanding that we use the 2018 IRC Residential Code Which appears to indicate a minimum of 21" clearance between front of toilet and anything else. I had a bathroom remodel company come give me a bid, and they claimed a minimum of 30" clearance is required...

Greetings. We’re looking to install a glass shower enclosure in a corner in a guest bath in a California. The existing space we have to work with is ‘very’ tight in all directions (see attached plan). When I Google the minimum allowed size, most of the home improvement websites cite 30” x 30”...