8.1 Fixtures, Equipment & Clearances

8.1 Fixtures, Equipment & Clearances

Quick Answer: Set product-accepted fixtures plumb, level, and square; use 15 / 30 / 21 inch spacing in public and employee restrooms; send public restroom fixture dimensions to 521 CMR 30.00; keep public lavatories in the same room as the toilet; size shower drains from 1½ inches (one 2.0 GPM head) up to 4 inches (50 GPM); keep drinking-water stations out of toilet rooms.

The Candidate Information Bulletin lists only two items under fixtures, but 248 CMR 10.10 is one of the densest sections in the Uniform State Plumbing Code (effective December 8, 2023). Massachusetts also publishes standing Board interpretations on Policies, regulations, and statutes for plumbers and gas fitters. The exam will mix the code text with those policies. This section is the installation and clearance chapter: how fixtures go in, how far they sit from walls and each other, and which Massachusetts rules sit beside 10.10 rather than inside it. Occupancy counts in 10.10 Table 1 (how many toilets a restaurant needs) belong with minimum-facilities study; do not skip spacing, drains, and accessibility pointers just because the CIB looks short.

Product-accepted fixtures, setting, and supports

Fixtures must be product-accepted, smooth, and impervious, and free of defects. Slip-resistant shower and tub surfaces are the stated exception when the listing requires them. Overflows, when provided, cannot hold standing water when the stopper is closed or when the bowl is empty, and they discharge on the inlet / fixture side of the trap. Toilet and urinal flush-tank overflows discharge only into the fixture they serve.

Install so the fixture and the floor around it can be cleaned. Joints at walls and floors are watertight. Floor-outlet and wall-hung fixtures are rigidly secured with corrosion-resistant fasteners. Wall-hung fixtures need a concealed metal product-accepted carrier so no strain reaches the discharge connection. Set fixtures plumb, level, and square to adjacent walls and to other fixtures.

248 CMR 10.10(1)(c)6 is the public and employee restroom spacing rule:

Grab bars, paper holders, and similar accessories are not obstructions. Child-care fixtures under 606 CMR 7.00 are carved out. Do not mix this 15-inch plumbing spacing with accessible water-closet layout from 521 CMR. When 248 CMR 10.10(15)(d)1 applies, public restroom fixture dimensions come from 521 CMR 30.00: Public Toilet Rooms, which is tighter than 15 inches to a sidewall.

Accessibility: 521 CMR, 248 CMR, and the Board handicap policy

248 CMR 10.10(15)(a) requires inhabited buildings to contain plumbing facilities, including for persons with disabilities, as required in 521 CMR. 10.10(15)(d)1 then sends public restroom fixture dimensions to 521 CMR 30.00. An extra accessible lavatory may sit inside a handicap stall in an otherwise compliant 248 CMR toilet room, and that lavatory's placement follows 521 CMR, not the 15 / 30 / 21 inch table. Wherever drinking-water stations are provided, they must be accessible to the physically impaired. In accessible restrooms that have urinals, at least one urinal is set for handicapped use (10.10(3)(i)).

The Board's Handicap Fixture Requirements interpretation (enacted August 12, 2008, still listed on Mass.gov) is the exam's policy overlay:

• 248 CMR governs plumbing. Fixture dimensions for public toilets are taken from 521 CMR. Room size, turning space, and door swing are Architectural Access Board issues, not a 248 CMR room-dimension table.
• When public restrooms are installed, handicapped fixtures are required. The Board used a dictionary reading of "public" — open to all persons.
• If the restroom is not public, that 2008 interpretation does not require handicapped fixtures. 521 CMR still has its own applicability (places of public accommodation, Group 1 / Group 2 dwellings). The plumber's job is to know which document is being asked: 248 CMR plumbing, 521 CMR 30 public toilets, or 521 CMR 44 Group 2 dwelling bathrooms.

Unisex / gender-neutral handicap toilet rooms may need a Board variance under 248 CMR 3.04(2), unless the men's, women's, and unisex fixtures already meet 10.10 Table 1 and the unisex room is counted only once.

Water closets

Public and employee toilets are elongated. Flush tanks must deliver enough water to flush the bowl. Float valves and ballcocks are anti-siphon and must refill the trap seal. A flushometer is accessible for repair, completes its cycle automatically, serves not more than one fixture, and is backflow-protected under 10.14(8). Public and employee seats are elongated open-front. Closed-front seats are allowed in single-family dwellings, condominiums, apartments, dormitories, hotel and motel guest rooms, and private office bathrooms. Maximum flush is 1.6 gallons. Public and employee toilets go in separate compartments, except single-user gender-neutral rooms and fixtures for children younger than six.

Prohibited: toilets with an invisible seal, a mechanical seal, or a device that can siphon from bowl to tank.

Lavatories — including the "outside the bathroom" policy

248 CMR 10.10(1)(c)7: lavatories in public and employee restrooms shall be located in the same rest room as the toilet. The code exception is narrow: hotels, motels, and dwellings may install the lavatory outside of but in close proximity to the bathroom. The Board's Lavatory Installed Outside of a Bathroom interpretation (enacted April 30, 2014) sits on the same Mass.gov policy list; Board agendas applying that interpretation treat commercial, industrial, and places of assembly as in-room lavatory work. Do not park a restaurant or office lavatory in the corridor and call it close enough.

Core restrooms are the other exception inside 10.10(15): where core restrooms are installed, lavatories may sit in an area common to males and females directly outside the toilet facilities within the rest room area, sized from the total fixture count.

Public and employee lavatories: maximum hot water 120°F, faucets 0.5 GPM, metering faucets 0.25 gallons per cycle. Residential lavatories: maximum 130°F. Group wash sinks count every 20 inches of usable length as one lavatory for drain and water sizing.

Commercial kitchen hand sinks are a policy trap. An older 10.14(3)(a) sentence limited "public" outlets to 110°F. The Board's Maximum Temperature for Hand Sinks in Commercial Kitchens interpretation (enacted October 2, 2013) says commercial kitchens are not "public" because only employees use those sinks, often next to 140°F pot sinks, and the Board allows 120°F. The current 248 CMR 10.14(5) temperature table lists Hand Sink in Commercial Kitchen: 120°F minimum and 120°F maximum, and Public & Employee Lavatory: 120°F. Use 120°F on both the policy question and the current table question; 110°F is the obsolete public-outlet figure the 2013 interpretation distinguished.

Showers, bathtubs, and the multiple-head drain policy

Secure every shower-head supply riser to the structure, exposed or not. Shower heads max 2.0 GPM. Supply each head through a product-accepted thermostatic, pressure-balancing, or combination valve. Limit mixed water to 120°F, adjusted by the installing plumber before final inspection. Hand-held showers follow the same control rules, need a vacuum breaker, and count as a shower head. Central ASSE 1070 mixing valves may replace individual 120°F shower valves if the mixer holds 120°F whenever showers are in use, a thermometer sits in the mixer outlet, and check valves sit on the hot and cold inlets.

The Board's Minimum Drain Size With Multiple Shower Heads interpretation (enacted November 27, 2013) still posted on Mass.gov allows a maximum of five shower heads on one 2-inch drain, counting 2 fixture units for the first head and 1 fixture unit for each additional simultaneous head. Five 2.0 GPM heads equal 10 GPM — the same 2-inch threshold as current 10.10(4)(b)3.a. Waste outlets need removable strainers at least 3 inches in diameter with openings at least ¼ inch, unless another strainer is product-accepted. Multiple heads without individual waste outlets must pitch so one head's water does not run across another head's floor.

Square or rectangular stalls rough in 32 × 32 inches (or 30 inches wide if at least 48 inches long). Neo-angle 38 × 38. Neo-round 36 × 36. Interior height 72 inches above the drain; glass enclosures must encompass a 30-inch circle. Pans turn up at least 3 inches above a finished threshold. Built-in tubs with shower heads need waterproof walls to 72 inches above the floor. Free-standing tubs and whirlpools: hot water not over 120°F via an ASSE 1070 limiter; whirlpools need pump access. A no-threshold accessible shower with a second bathroom floor drain may tie that floor drain into the vertical piping between the shower drain and the trap weir.

Urinals, drinking-water stations, and floor drains

Urinals have integral traps. Flush only by automatic tank or flushometer with a backflow preventer. Maximum 1.0 gallon per flush. Automatic tanks that serve more than one urinal must flush all of them at once. Outside private residences, finish 1 foot in front of the lip, 1 foot each side, and walls to 4 feet with non-absorbent materials. Side shields for privacy. Waterless urinals need a liquid-barrier trap seal, must sit downstream of at least one water-supplied fixture, and get a water line roughed in for future use. Trough, stall-type, exposed-trap, and invisible-seal urinals are prohibited.

Drinking-water stations (with or without drain; bottle fillers with a drain count as stations) need a trap of at least 1¼ inches, self-closing NSF-61 fittings, and shall not be installed in toilet rooms. Stations without a drain still get rough plumbing for a future connection. Bi-level stations count as one fixture in 10.10 Table 1. Discharge may be direct or indirect. Principle 24 and the 10.03 definition both keep drinking water out of rooms that contain toilets or urinals.

Floor and trough drains: 3-inch water seal, removable strainers, readily cleaned, 2-inch minimum outlet. Grade them to drain the floor from all directions. Provide a readily accessible automatic trap-resealing device, with three exceptions: continuous or semi-continuous indirect waste under 10.12; product-accepted barrier devices on up to 90% of drains in a multi-drain room that still has at least one automatic primer (never in a one-drain room); or an accessible wall hydrant in the room in place of a primer. Required in commercial or public restrooms with more than one flushing fixture (place the drain in the urinal vicinity when a urinal is present), in commercial/industrial and multi-family laundries, and in commercial boiler rooms. Those same commercial/public restrooms also need a hose connection (10.10(15)(e)).

Exam traps for 8.1

• 15 inches is not the accessible water-closet number. It is the 10.10 plumbing spacing floor. Public accessible fixture dimensions are 521 CMR 30.00.
• Public lavatory in the hall fails 10.10(1)(c)7. Hotel, motel, and dwelling lavatories may sit just outside. Core restrooms may share lavatories in the restroom area outside the stalls.
• A 1½-inch shower drain is only for one 2.0 GPM head (or a tub). Simultaneous heads start at 2 inches.
• Drinking fountains do not live in toilet rooms, even if the restroom "needs" a fixture count.
• 110°F is not the commercial kitchen hand-sink answer on current Board policy or the 10.14(5) table.