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Every mechanical room shall have a minimum of one hose bib.

Piping dead legs are prohibited. During renovations, dead end piping must be removed to within six inches of mains (or what is appropriate).


Any pipe, fitting, or plumbing fixture intended to convey or dispense water for human consumption shall be certified to NSF-61 Annex G or NSF372.

Design water supply piping for human consumption so that food areas, break-room sinks, and water fountains are not at the end of a plumbing run, and are located so that the water supply has a high rate of turn-over to assure high water quality.

Water Closets

Specify high efficiency china and flush valves both rated for 1.28 or less. (consider 1 gpf) China shall be wall hung. Flush valves shall be manual except ADA facilities shall incorporate infrared. The flush valve and china combination shall remove a minimum of 1000 grams of waste in a single flush per MaP testing protocol. Provide the following owner preferred alternates for the flush valves: Sloan, Zurn, and American Standard.


Specify china and flush valves rated for 0.125 gpf. Flush valves shall operate by infrared sensor. Provide the following owner preferred alternates for the flush valves: Sloan, Zurn, and American Standard. Water Closets – NSP 61/ASME 61.9 Approved.


Specify low-flow lavatories with faucet aerators with push timed or engaged drop stick metering.


Specify low-flow showers with single handle that enables off/on temperature maintenance.

Floor Sinks and Drains

  1. Within a 2′ radius of floor sinks and drains, slope the floor downward 1/8″ per foot towards floor sinks and drains.
  2. Floor sinks and floor drains shall be slightly recessed below the floor.
  3. Prior to the pouring of concrete floors, floor sinks and drains shall be secured anchored into place. The contractor is responsible for reinstalling any floor sinks which are higher than the surrounding floor surface.
  4. For new construction, provide recessed floor sinks or hub drains for each source of equipment condensate. Verify the elevation of floor sinks prior to pouring.
  5. Provide floor sinks in areas prone to flooding and for the collection of condensate.
  6. Do not provide excess floor sinks in areas that are not required.
  7. Provide floor drains which require removal of the cover with a “special tool” or by qualified staff.
  8. Floor sinks for exterior stairwells, if required, shall be a minimum of 4″ with a minimum 12″ x 12″ x 6″ drain well with grate-type cover.

Water Coolers

Provide manufacturer recommended clearances. Provide ½” piping min. to water coolers to prevent bubbler height bounce with pressure fluctuation. Do not specify remote mounted condensing units. Condensing units should be accessible from the front of water cooler and in same enclosure.

Remote and stand-alone water coolers will be installed with at least the minimum side, front, rear and floor air flow clearances that are recommended by the manufacture and will not be recessed into areas with poor air flow. The water supply shall not be tied into the same supply water that feeds the rest room fixtures to prevent bubbler height bounce when any flush valve is activated.

Specify electric water coolers equipped with bottle filling stations. Specify as the basis of design Elkay EZH20 LZSTL8WSLK for the bi-level and EZH2O LZS8WSLK for the single bottle filling units. The equivalent Halsey Taylor model is approved.


For areas using large quantities of bleach, such as BSL3, BSL2+ labs, HIV labs, etc., sinks and drains shall be compatible with bleach. Stainless steel is not acceptable for frequent use with bleach.

Mixing valves

Mixing valves shall be installed below ceilings.

Provide isolation valves on piping branches.

Provide separate piping with a set of isolation valves for each specialty lab and to each bathroom of a bathroom group to allow for outages of individual spaces without affecting the adjacent space. For spaces with restricted access, the isolation valves must be located outside the room.

Service entrance domestic backflow protection

Provide dual, parallel backflow devices to protect the building domestic supply. At a minimum, back flow devices shall meet OWASA guidelines.

Backflow devices capable of dumping water (RPZs)

  1. Install in a location that may not flood the building such as an exterior hotbox or heated, above grade room that only opens to the exterior.
  2. In unusual cases, when RPZs must be located in a room that opens to the interior, RPZs must relieve to a funnel drain connected directly to the exterior. The funnel drain must not be equipped with a backwater valve. Provide an exterior concrete gutter or other means to conduct relief water 4′ to 10′ away from the building foundation and coordinate with University landscape architect. Provide a recessed floor sink. Slope the floor towards the drain. Provide a concrete curb or trench drain at the interior door. Walls shall be designed for splashing water. Seal the floor and the bottom 6″ of walls to an elevation of 6″. Seal the room fairly air tight and provide a door sweep to prevent a negatively pressurized building from drawing exterior air through the relief drain.

Backflow devices requiring maintenance shall be less than 5′ above the floor.

Domestic water shall not be used as a primary cooling source. Domestic water used as a back-up cooling source shall be reclaimed.

When domestic or reclaim water is used for back-up cooling, there shall be a separate branch pipe serving the building’s back-up cooling needs with a single switch over valve monitored by the BAS.

Large quantities of domestic water used to create vacuums for lab equipment shall be reclaimed.


Provide isolation valves on both sides of and all equipment that requires periodic replacement such as equipment, PRVs, meters, pumps, coils, tanks, heat exchangers, etc.

Vacuum Pumps, Air Compressors, and Air Dryers

  1. Provide 25 micron filter and pressure regulators with isolation valves on each side. Locate in an accessible location and not located behind the equipment.
  2. Provide one foot clearance in rear to wall and two foot clearance on each side.
  3. Provide washable condenser filter.
  4. PLCs: Provide a back-up copy of the programming software, ladder logic and database for all PLCs.
  5. Air compressor storage tanks shall be a minimum of 4 cft storage for each scfm of compressor capacity.
  6. Desiccant Dryers
    1. Provide a wet and dry storage tank on each side of the air dryers.
    2. For desiccant dryer final filters, provide audible alarms, alarm signal to the BAS, and a 4″ differential pressure gauge. Alarms shall be powered by 120 VAC, not battery-powered.
  7. Provide an exploded view parts drawings with parts numbers with O&M manuals.
  8. Vacuum pump style and features shall be selected to provide minimal water usage.
  9. Liquid ring vacuum pumps shall be equipped recirculating sealant water.

Pure-water (RO or DI)

In closed loop systems equipped with DI beds, provide a resistivity meter in the return piping. Provide pressure gauges and sample ports on both sides of each filter and component.

Sump Pumps

  1. Elevators shall be provided with sumps and sump pumps piped to the sanitary sewer.
  2. Provide a high-level alarm and monitoring with the BAS.
  3. For hydraulic elevators, equip sump pumps with oil-minder features.
  4. Provide lifting rails for sumps deeper than 8′.
  5. Lifting rails and mounting hardware for lifting rail and pump bases shall be stainless steel.

High Purity Water Systems (RO and DI Water)

For large systems, RO pretreatment is required. Provide a single, centralized RO system