Public Restroom Hot Water Temperature in Ohio: The 85 to 110°F Rule
By the ACC Solutions team
Short answer: in Ohio, the sinks in a public restroom used by customers, patrons or visitors must deliver tempered water, which the plumbing code defines as 85°F to 110°F, through a temperature-limiting device that meets ASSE 1070. If the business serves food, Ohio's food code separately requires every handwashing sink to provide water of at least 85°F through a mixing valve or combination faucet. So the target window for a restaurant's customer restroom sink is 85°F to 110°F.
This guide covers commercial spaces in Cleveland and across Ohio. It quotes the Ohio Plumbing Code, Chapter 4 (the 2021 International Plumbing Code as Ohio adopted it) and the Ohio Uniform Food Safety Code rule 3717-1-05.1, read November 11, 2026. Your local building official and health inspector make the final call on your project.
What "tempered water" means in the code
The code's definitions chapter sets three terms that matter here:
- Tempered water: "Water having a temperature range between 85°F (29°C) and 110°F (43°C)."
- Hot water: water at 110°F (43°C) or more.
- Toilet facility: a room or space with at least one water closet and one lavatory.
Section 419.5 then says tempered water "shall be delivered from lavatories and group wash fixtures located in public toilet facilities provided for customers, patrons and visitors," through "an approved water-temperature limiting device that conforms to ASSE 1070/ASME A112.1070/CSA B125.70." Ohio's own amendments to Chapter 4 (OAC 4101:3-4-01) don't change Section 419.5.
Two practical takeaways. First, the rule is about the restroom that customers and visitors use, so staff-only restrooms aren't named in 419.5. Second, the device is the point: you can't meet 419.5 just by turning the water heater down, because the code calls for an ASSE 1070 limiting device at the fixtures.
The restaurant twist: Ohio's 85°F food-code minimum
Ohio's food code rule 3717-1-05.1(C) adds requirements for every handwashing sink in a food operation, including the ones in the kitchen:
- Water "at a temperature of at least eighty-five degrees Fahrenheit" through a mixing valve or combination faucet.
- No steam mixing valves at a handwashing sink.
- A self-closing, slow-closing or metering faucet must run for at least 15 seconds without being reactivated.
The same rule says the plumbing system is to be designed, built and installed according to the Ohio plumbing code. In a restaurant's customer restroom, both rules apply: at least 85°F from the food code and 85°F to 110°F from the plumbing code. For the rest of a food-service build-out, see our page on restaurant plumbing in Cleveland.
Other fixtures with temperature limits
Restroom sinks aren't the only fixtures the Ohio Plumbing Code caps. Commercial jobs often include these:
| Fixture | Code section | What it requires |
|---|---|---|
| Public restroom lavatories and group wash fixtures | 419.5 | Tempered water (85 to 110°F) via ASSE 1070 device |
| Individual showers and tub-showers | 412.3 | Balanced-pressure, thermostatic or combination valve (ASSE 1016 or ASME A112.18.1), limited to 120°F max |
| Gang showers on one tempered supply | 412.4 | Automatic temperature control mixing valve (ASSE 1069 or CSA B125.3), or individual valves at each head |
| Bathtubs and whirlpool tubs | 412.5 | ASSE 1070 device (or ASSE 1082/1084 water heater), max setting 120°F |
| Bidets | 408.3 | Not greater than 110°F via ASSE 1070 device |
| Pedicure chairs and footbaths | 423.3 | Not greater than 120°F via ASSE 1070 device or ASSE 1082 water heater |
| Emergency showers and eyewash stations (hot and cold supplied) | 411.3 | Temperature-actuated mixing valve complying with ASSE 1071 |
For tubs, Section 412.5 also requires access to adjustable ASSE 1070 devices, with an exception for some nonadjustable devices.
Where this comes up on real jobs
- A new tenant build-out. Plan reviewers look for the limiting device on customer restroom lavatories. Show it on the drawings with the fixture count. Our guide to how many restrooms a commercial space needs in Ohio covers the count.
- A water heater replacement. A new heater set hotter than the old one can push restroom sinks above 110°F if there's no working limiting device. See our post on commercial water heater replacement permits in Ohio.
- Customer complaints of scalding or ice-cold water. A failed or misadjusted mixing valve is a common suspect, and so is a long run from the water heater.
- A health inspection at a restaurant. A handwashing sink below 85°F, or a metering faucet that shuts off in under 15 seconds, is a food-code item.
A quick check you can do before a plumber comes
- Run the restroom sink on full hot for a minute and measure the water with a kitchen thermometer.
- Write down the reading, the time of day, and whether other fixtures were running.
- Look under the sink, or in an access panel nearby, for a small mixing valve, and photograph its label.
- Note the water heater's age and setting if you can see them.
That's enough for a plumber to tell you whether the issue is the device, its setting or the supply. Don't take apart or readjust a valve yourself in a space open to the public.
How ACC helps
ACC Solutions coordinates commercial plumbing in Cleveland and Cuyahoga County, including restroom build-outs, fixture work and water heater replacements, and we quote after a walkthrough (here's what the walkthrough covers). Send us the thermometer readings and photos by email or the contact form. Call the plumbing desk at (216) 480-8899 or request a commercial plumbing project review.
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
We work asynchronously, so you can reach us by email or the contact form from any time zone; you don't need to catch us during Ohio business hours.
Frequently Asked Questions
What temperature should hot water be in a public restroom in Ohio?
Public restroom lavatories for customers, patrons and visitors must deliver tempered water, which the Ohio Plumbing Code defines as 85°F to 110°F, through an ASSE 1070 temperature-limiting device (Section 419.5).
What is the minimum handwashing sink temperature for restaurants in Ohio?
Ohio's food code, rule 3717-1-05.1, requires a handwashing sink to provide water of at least 85°F through a mixing valve or combination faucet.
Does the tempered water rule apply to employee restrooms?
Section 419.5 names public toilet facilities provided for customers, patrons and visitors. In a food operation, every handwashing sink, including staff sinks, still has to meet the food code's 85°F minimum.
Can I just turn down the water heater to meet the code?
Section 419.5 calls for an approved water-temperature-limiting device that conforms to ASSE 1070, so turning down the heater alone doesn't meet it.
How long must a metering faucet run in an Ohio restaurant?
At least 15 seconds without being reactivated, under rule 3717-1-05.1.
