Plumber's Licensing Exam: Faucets And Fixture Fittings

When people turn on a faucet, they expect the delivery of safe water at a volume and temperature suitable for their use. They aren’t concerned with low volume, scalding, or an unsafe supply due to a backflow condition at the faucet. That’s how it should be. Faucets are meant to be taken for granted. The plumbing codes ensure this.

Objectives
- Gain familiarity with faucet requirements
- Identify various types of flushing devices
- Explain water conservation requirements

Key Terms:
flush tank
flushometer tank
flushometer valve

From the mundane to the exotic, faucets are some of the most taken-for-granted items in buildings.

The two figures below show examples of a plain, utilitarian faucet and a highly decorative faucet.

Figure: Basic Lavatory Faucet

Figure: Fancy Lavatory Faucet

Real-Life Situation: Ace Plumbing Company is bidding on another renovation. This time it involves the one common bathroom on the second floor of a college dormitory dating from the 1930s. All the walls are large tile. The old floor-mount urinals are all flushed together by a tank behind the wall. Tiny dental lavatories line the interior dividing walls. The water closets have washout bowls, and their flush tanks are equipped with flush ells. All of the showers have two-handle faucets that are original. This equipment was great stuff to have been in service this long, but can and should it be salvaged? Give Sophia some help deciding what to do here. Does any of this stuff still meet code requirements? Remember, we’re dealing with an institution here—budget, budget, budget.
 
Water Consumption
Heightened awareness of, and in many cases the necessity for, water conservation drove the authorities having jurisdiction to limit maximum flows from faucets. We are only touching on faucet flows at this point in the book in keeping with the subject of this guide.

The table below provides a quick look at the maximum water flows specified by the IPC.

Design
We all assume that with any two-handle faucet the hot will be on the left and the cold will be on the right. That’s tradition, right? It is also part of the UPC. Section 415.0 clearly states that single-handle mixing faucets need to have markings on the faucet trim to indicate hot and cold to the user. (Refer to IPC 425.1.1; UPC 404.0, 415.0, 603.4.5)
Handheld showers create a strong potential for a backflow condition, because the business end could be left hanging in a filled bathtub. Therefore, all hand showers are required to have either an integral back-flow preventer or they must be connected to an external backflow preventer. Without this protection, bathtub water could be sucked into the potable water distribution system of the building—definitely not a good thing.

Tips
Some faucet manufacturers make tub and shower faucets and lavatory faucets in which the hot and cold side can be reversed by making an internal adjustment. This is useful when it is more convenient to rough-in the hot and cold pipes on the “wrong” side. This situation can occur when bathtubs or lavatories are back to back on the same wall, as can be found in apartment complexes. One hot supply pipe and one cold supply pipe can supply both fixtures.

Fact: The first modern plumbing code was the English Public Health Code of 1848. The first American plumbing code was the Metropolitan Health Law adopted in New York City in 1870. The connection between bacteria and disease was made after the Civil War and the importance of sanitation increased the focus on sanitary plumbing systems.
Faucet outlets must be designed to have an air gap of at least 1 inch above the flood-level rim of the fixture it is serving. In the event that the design of a fixture prevents this, the outlet must be protected with a vacuum breaker mounted at least 6 inches above the flood-level rim of the fixture. Much of the body of both plumbing codes is aimed at the prevention of backflow conditions. That’s the whole point of having a plumbing code: protecting the health of all of those who use the plumbing systems we create. The advancement of modern plumbing codes has increased the health of our nation many times over.
All plumbing fixtures must have strainers in their drains to catch debris and minimize the size of solids passing down the drain. This helps prevent blockages. The exception to this rule is water closets and siphon-action or blowout urinals. Even field-built fixtures like garbage can washers and trough drains need a strainer.
Every water closet is required to be equipped with some kind of device to flush it. (Thank goodness!) That goes for any fixture that drains with a siphon, like urinals and bedpan washers. Either a flush tank, flushometer tank, or a flushometer valve is required. Every fixture must have its own individual flushing device. The days of the common flush tank and automatic common flushing valves are gone. This rule helps with water conservation. All flushometers must have a vacuum breaker integral with the valve. The fill valve in the gravity flush tanks must prevent back-siphonage.

Temperature Control
According to the UPC, 120°F is the highest temperature water allowed to flow from a lavatory faucet installed in a public facility. For the IPC, the maximum temperature for public lavatories is 110°F. Table 424.4 of the IPC shows this requirement (Table below). Read this guide on Water heaters and take a look at the table above to see how severe burns can be, even at 120°F. (Refer to IPC Table 424.4; UPC 413.1)

Caution: An average of 300 children a day are taken to emergency rooms in the United States for burns from hot water. According to the National Safety Council, the United States has the highest rate of burns in the industrialized world. In the United States, after congenital malformations, disorders related to short gestation and low birth weight, and sudden infant death syndrome, burns are the leading cause of death for children from birth age through five years. The thinner skin of a child burns much faster than an adult’s skin.

It is important to note that the temperature control for public lavatories cannot be the thermostat on the water heater. This rule obligates the installer to control the temperature with an approved tempering valve or some other type of secondary temperature control. This is a smart rule since water heater thermostats are good for general temperature control, but are not designed for highly accurate temperature control. This same temperature (120°F) applies to all bathtubs and showers, whether they are public or private.
Both the UPC and the IPC require pressure-balancing faucets for tubs and shower valves. Pressure-balancing faucets react to a sudden drop in pressure of either the cold or the hot water supply to the faucet. If the hot water pressure drops, such as when a washing machine starts to fill with hot water, a mechanism inside the body of the faucet reduces the water delivery from the cold side of the faucet, which keeps the outlet water at a relatively stable temperature. The same is true when someone flushes a water closet and the cold water supply pressure suddenly drops. The internal mechanism, usually a sliding piston, moves to reduce the hot water flow to the shower head or tub spout to prevent scalding of the bather. When multiple showers are installed in a locker-room type of facility, hot water temperature control can be achieved with one main mixing valve rather than a temperature control at each shower fixture.