How many hand sinks and mop sinks does a Maricopa County restaurant need, and where?

Under Hand Wash Sinks, the guide says to provide a sufficient number of hand-wash sinks, easily accessible with no barriers. The distance rule is the quote above: within approximately 25 feet of the listed areas, "without obstruction (i.e., a door)." A sign, sticker or poster reminding food employees to wash their hands is also required.

On splash protection, the guide says: "Splash guards are required when a hand-wash sink is located within 24 inches of a food contact surface, food/utensil storage shelves, food service areas, a vegetable preparation sink, or a dish washing sink." The guard is waterproof, at least as high as the faucet (the apex of the faucet neck) and as deep as the hand sink, securely fastened, and sealed at the seam with silicone.

For the water supply, the restroom provisions in the same section say each hand-wash sink gets hot and cold water, or tempered water through a mixing valve or combination faucet. A self-closing, slow-closing or metered faucet must give a pressurized flow of at least 15 seconds without reactivation, and hot or tempered water must reach the faucet within 45 seconds. The guide quotes IPC 607.2: the developed length of hot or tempered water piping from the source to the fixtures must not exceed 50 feet, and recirculating or heat-traced piping counts as a source.

For the mop sink, the guide requires "At least one approved large floor-mounted, wall-hung, or leg-supported service sink of a type suitable for janitorial and building maintenance purposes." It lists mop sinks and basins, utility tubs, janitor sinks, slop sinks, or a curbed facility with a sanitary drain, all with hot and cold water for mop use. The faucet must be a combination mixing faucet with an approved backflow prevention device. Toilets and urinals "may not be used as a service sink for the disposal of mop water."

• Service sink. The guide's name for the mop sink or curbed cleaning facility.
• Obstruction. The guide's own example is a door.
• Food contact surface. The guide does not define it in this section. The 24-inch splash guard trigger names food contact surfaces, shelves, service areas, a vegetable prep sink and a dish sink.
• Within approximately 25 feet. The guide's word is "approximately." The guide does not say how the reviewer measures it.

Food establishments whose plans are reviewed under the Maricopa County guide. The service sink rule is written for "all permitted establishments."

The county's service sink line cites the Food Code and the plumbing code together: "(FC §5-203.13), IPC §403, §613.1)". A city's plumbing-code amendment does not by itself change that county line. Mesa's checklist, for example, says "Service sinks shall not be required for Groups B and M where occupant loads do not exceed 100 persons. (M-IPC 403.1)". That changes the city's plumbing fixture count. The checklist says nothing about the county guide, so a county-reviewed food establishment in a Mesa B or M space should still plan for the service sink the guide asks of "all permitted establishments." A non-food B or M tenant in Mesa is the case the amendment is written for.

A fast-casual kitchen. The designer places one hand sink at the line, one at the dish area and one at the bar. Each is inside 25 feet of its stations with no door in the way, the splash guard is drawn where the sink sits close to the prep sink, and the reviewer approves the layout.

A hand sink the reviewer moves. The hand sink sits beside the walk-in, across a swinging door from the cooks. The distance is short, but the guide counts a door as an obstruction, so the plan moves the sink.

The edge case. A two-story brewery restaurant puts its single mop sink on the ground floor. The guide says if there is no elevator, a service sink must be available on each floor, because carrying a mop bucket up or down stairs or up ladders is not considered conveniently located.

1. 1Mark every workstation, prep area, bar, wait station, ice machine and ware washing area on the floor plan and draw a 25-foot circle from each hand sink.
2. 2Check each hand sink against food contact surfaces, shelves, service areas, prep sinks and dish sinks within 24 inches, and add splash guards where needed.
3. 3Confirm the hot water run to every hand sink fits the 50-foot developed length and the 45-second delivery limit, adding recirculation or heat trace if not.
4. 4Place the service sink or curbed basin so it is reachable by everyone, with a hot and cold mixing faucet and backflow protection.
5. 5Show all of these fixtures on the plumbing schedule and floor plan before submitting through the Permit Center.

• Myth: Close enough through a door. The guide's own example of an obstruction is a door.
• Myth: The splash guard is optional. It is required within 24 inches of the listed surfaces.
• Myth: Any sink can take mop water. The guide requires a service sink or curbed facility, and says toilets and urinals may not be used for it.
• Myth: Mesa's 100-person exception drops the mop sink for a restaurant. The amendment is to Mesa's plumbing fixture table. The county guide's service sink rule is written for "all permitted establishments" and cites FC 5-203.13 as well as IPC 403.
• Myth: A water softener must stay away from the mop sink. The guide says stationary equipment such as water softeners or water filter systems "may not obstruct the mop basin or sink" and asks for space adjacent for mop buckets.