Do I Need a Service Sink? Ohio Commercial Mop Sink Requirements
By the ACC Solutions team
Short answer: most commercial buildings in Ohio need at least one service sink (a mop sink or similar fixture for cleaning tools and dumping mop water). The Ohio Plumbing Code's Table 403.1 lists "1 service sink" for nearly every occupancy, with one clear exception: business and mercantile spaces with an occupant load of 15 or fewer don't need one. Restaurants and other food operations need one under Ohio's food code no matter how small they are.
This post is by the ACC Solutions team (Licensed General Contractor, License #CR25025171). It summarizes the Ohio Plumbing Code (the 2021 International Plumbing Code as adopted and amended by Ohio in OAC Chapter 4101:3) and the Ohio Uniform Food Safety Code, read November 13, 2026. It's general information, not legal advice; your building department and, for food businesses, your health department make the final call. If you're planning a build-out, our commercial plumbing team quotes after a walkthrough.
Where the requirement comes from
Ohio's plumbing code is the 2021 IPC with Ohio's own changes. Chapter 4 sets the minimum fixtures in Table 403.1, and the "Other" column is where the service sink lives. Ohio's Chapter 4 amendments in OAC 4101:3-4-01 change how occupant load is set and how swimming pool fixtures are counted, and they don't remove the service sink line. Ohio also adds an exception to Section 403.1: buildings under 100 square feet don't need facilities if fixtures are available within 500 feet.
Service sinks by occupancy in Table 403.1
Occupancy (examples from the table) | Service sink requirement |
|---|---|
Assembly: restaurants, banquet halls, bars, theaters, places of worship, gyms, libraries | 1 service sink |
Business: offices, banks, professional services, ambulatory care | 1 service sink (none if occupant load is 15 or fewer) |
Mercantile: retail stores, shops, markets, service stations | 1 service sink (none if occupant load is 15 or fewer) |
Educational, factory and industrial, storage (warehouses) | 1 service sink |
Institutional: custodial care, prisons, adult and child day care | 1 service sink |
Hospitals and nursing homes (care recipients) | 1 service sink per floor |
Residential: hotels and motels, dormitories, congregate living for 16 or fewer | 1 service sink |
Apartment houses; one- and two-family dwellings | No service sink line; kitchen sink per unit and washer connections instead |
The table counts minimum fixtures "based on the actual use of the building or space," and uses not listed are considered individually by the code official. So the sink you need follows the use group on your plans, not the name on the lease.
The small-office and small-shop exception
Table 403.1 footnote e: "For business and mercantile classifications with an occupant load of 15 or fewer, service sinks shall not be required." Occupant load is the number set under the building code (Section 1004), which is usually based on floor area and use, not your headcount. Ohio's amendment lets the building official set an alternate occupant load when the real number will be very different, and that alternate basis is written into the certificate of occupancy. If you're counting on the exception, get the occupant load in writing during plan review.
The exception is for Business and Mercantile only. Educational, institutional, day care, factory and storage uses don't get it. And even where a small food business is classified as Business or Mercantile, the food code below still requires a service sink.
Food businesses: the health code requires one regardless
Ohio's food code, OAC 3717-1-05.1(I) (effective September 5, 2024), says: "At least one service sink or one curbed cleaning facility equipped with a floor drain is to be provided and conveniently located for the cleaning of mops or similar wet floor cleaning tools and for the disposal of mop water and similar liquid waste." That applies to food service operations and retail food establishments even where the plumbing code's footnote e might otherwise exempt a small mercantile space, such as a small grocery or a coffee counter inside a shop.
Two related rules trip up food operators:
Don't use the other sinks. Under OAC 3717-1-06.4, lavatories, food preparation sinks and warewashing sinks aren't to be used for cleaning maintenance tools, holding maintenance materials or disposing of mop water. Planning to dump the bucket in the three-compartment sink is a violation, not a workaround.
Backflow at the hose. OAC 3717-1-05.1(J) requires backflow protection at each point of use, including on a hose bibb when a hose is attached. Service sinks usually have a threaded faucet for a hose or chemical dispenser, so plan for the right device there.
Tenant spaces in malls: the 300-foot rule
Section 403.6: service sinks aren't required in individual tenant spaces in a covered mall if service sinks are within 300 feet of travel of the most remote point in the tenant space and not more than one story above or below it, on an accessible route. That exception is written for covered malls. A strip-center tenant should ask the building official before assuming a shared janitor closet down the hall covers them.
Five things to settle before you rough in a service sink
Confirm the occupancy and occupant load on the plans. That decides whether footnote e applies.
If you serve or sell food, plan the service sink or curbed cleaning facility with a floor drain from day one, because the health code requires it.
Pick the location. The food code says "conveniently located." In practice, put it where staff will use it, not behind stored stock.
Plan the faucet and backflow device for hoses and chemical dispensers.
Count it on the permit. Many Cuyahoga suburbs price permits per fixture; in Warrensville Heights, for example, a slop sink is its own line on the commercial permit. See our Warrensville Heights commercial plumbing guide.
Common mistakes
Assuming "small" means exempt. Only Business and Mercantile at 15 or fewer get the footnote, and food operations never do under the health code.
Treating a floor drain alone as the answer. The food code's alternative is a curbed cleaning facility with a floor drain.
Leaving it off the drawings. Adding a fixture after plan review means a revised permit and another inspection.
For the rest of the fixture count (toilets, lavatories and drinking fountains), see our posts on commercial restroom fixture counts in Ohio and drinking fountain requirements in Ohio. Restaurant owners should also read our guide to grease interceptor requirements.
Planning a build-out or a change of use? Call the ACC plumbing desk at (216) 480-8899 or request a commercial plumbing project review. We quote after a walkthrough.
ACC Solutions team · Licensed General Contractor, License #CR25025171
Plumbing desk: (216) 480-8899 · Email: support@accmgmtsolutions.com · Contact form
6545 Market Ave N, Canton, OH 44721
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