These come from the FDA Food Code, which nearly every state adopts. A health inspector checks for them on plan review and at inspection — regardless of your state:
Also required in most kitchens: a mop/service sink (cleaning-water disposal), mechanical exhaust hood (Type I over grease/smoke), adequate hot water, indirect waste/air gaps on food & warewashing equipment, and a grease interceptor where local plumbing code requires it.
Licensing authority: Local health departments; MDARD for certain categories. Regime: Local licensing + statewide unit class.
Two distinct classes, and the choice shapes the whole build. MOBILE FOOD ESTABLISHMENT: not fully equipped for full service, therefore MUST return to a licensed commissary at least once every 24 hours; the commissary licence number must appear on the application or it will not be processed. TRANSITORY FOOD UNIT (previously Special Transitory Food Unit / STFU): a permanently licensed operation that may work anywhere in Michigan without the 14-day temporary limit AND is NOT required to return to a commissary. Fee $135 whether issued by a local health department or MDARD; MDARD plan review $197. Requires submitted standard operating procedures and plan review. Notification of intent to operate must be sent to the local jurisdiction at least 4 business days ahead. Restaurants, catering trucks and event vendors sit with the local health department; groceries, bakeries and fair concessions sit with MDARD.
Mobile/food-truck reciprocity: PARTIAL - the Transitory Food Unit (formerly STFU) class is licensed to operate statewide
New builds and remodels almost always require a plan review and a pre-opening inspection. Submit your equipment layout early — the sink count, hood, and hot-water sizing are the usual sticking points.
See restaurant-equipment dealers in Michigan → — many do design + fabrication and know local plan-review requirements.