Medical and Dental Office Plumbing in Phoenix

Any dental office that places or removes amalgam fillings and drains to a city sewer needs an amalgam separator. The EPA's Dental Amalgam Rule (40 CFR Part 441) requires one or more separators that meet ANSI/ADA Specification 108 or ISO 11143, with at least 95 percent removal, sized for the office's maximum flow. Existing offices had to comply by July 14, 2020. New offices comply from the first day they discharge.

A few offices are outside the rule. Practices that do only oral surgery, orthodontics, periodontics, prosthodontics, oral pathology or oral radiology are exempt, and so are mobile units. Offices that don't place amalgam and remove it only in rare emergencies can certify that instead. The City of Phoenix flyer adds a useful line: an office that stocks amalgam capsules clearly intends to place amalgam.

Watch the calendar on older equipment. A separator installed before June 14, 2017 is grandfathered only until June 14, 2027, or until it has to be replaced, whichever comes first. If yours predates 2017, plan the swap now instead of during a busy week next spring.

Gilbert adds its own line: Town Code 66-248 requires amalgam traps on all equipment that might carry amalgam waste to the sewer.

In Phoenix, the city's Water Services Department is the Control Authority, so the One-Time Compliance Report goes to its Environmental Services Division. A new office files within 90 days of first sending wastewater to the sewer. A new owner files within 90 days of the sale, even when nothing in the operatory changed.

After that, the rule is about records. Keep these for at least three years:

1. 1The date, the person and the result of each separator inspection.
2. 2Every canister or container replacement.
3. 3Each amalgam pickup or shipment, and the disposal facility that took it.
4. 4Any repair or replacement of the separator, with make and model.

Keep the manufacturer's operating manual on hand too. And check what goes down the vacuum lines: bleach, chlorine, iodine and peroxide line cleaners outside pH 6 to 8 are banned on lines that drain to the sewer. The Phoenix industrial wastewater permit page covers the city's wider pretreatment program.

Phoenix puts medical buildings on its list of facilities that need backflow protection. City Code 37-144 lists hospitals, medical buildings, clinics, nursing homes and research laboratories among the facilities that need an air gap or a reduced pressure (RP) assembly on the water service. Phoenix's 2024 plumbing code amendments go further and call for a secondary RP assembly at hospitals, surgical clinics, medical buildings and labs.

Every assembly is tested at least once a year by a certified tester, and the customer sends the results to the city and keeps records three years. Inside the suite, the 2024 IPC also requires backflow protection on the water supply to dental pumping equipment. Not sure which assembly you have? Here's RPZ vs double check, and what happens when an assembly fails its test.

Dental and medical suites carry plumbing a normal office never sees. Sterilizers that discharge potable water to the drain do it through an indirect waste pipe with an air gap under the 2024 IPC, so a drain backup can't reach the sterilizer. Vacuum pumps, compressors and cuspidors each have water feeds and drains that need to be where the equipment maker's drawings say.

Two local wrinkles. Phoenix amended IPC 803.1 so corrosive waste has to be neutralized or treated by an approved device, and notes that diluting chemical waste instead is prohibited under 40 CFR 403.6(d). Paradise Valley requires dental vacuum piping under an on-grade slab to follow drawings from a registered design professional. The takeaway: plan the under-slab work before the concrete, not after.

Opening or expanding a practice in Phoenix means a permit. The city's building code requires one before you install, alter or replace a plumbing system, and its short list of exemptions covers small repairs, not new chairs, sinks or equipment rooms. Phoenix does let you repair or replace an existing secondary backflow assembly of 2 inches or smaller without a permit, as long as a certified tester's report goes to the city. See the Phoenix commercial TI permit page and commercial tenant improvement plumbing.

We clear commercial drains and jet lines, replace backflow assemblies, install water heaters, run gas lines, and camera and repair sewer lines. We work around patient hours, including evenings and weekends, and we're available 24/7 for a backup that can't wait. You get an upfront price before work starts, and estimates are free.