Journeyman Plumber (UPC/IPC) — All Questions

A clothes-washer standpipe trap must be located at what height above the floor?

• a.At the ceiling
• b.48 in above the floor
• c.Below the floor
• d.6 in to 18 in above the floor✓

The standpipe trap must be set between 6 in and 18 in above the floor (IPC 802.4), keeping the seal accessible and at a workable height while the standpipe rises above it. Below the floor or at the ceiling is outside the allowed range.

The floor of a shower compartment must slope to the drain at a minimum of:

• a.1/4 in per ft✓
• b.1/8 in per ft
• c.1 in per ft
• d.1/2 in per ft

A shower floor must slope to the drain at not less than 1/4 in per ft (about 2 percent) so water does not stand (UPC 408.5 / IPC 417.5.2). 1/8 in per ft is too flat and 1/2 in or 1 in per ft is steeper than required and awkward to stand on.

A model-code showerhead is limited to 2.5 gpm at 80 psi. Where several showerheads serve one shower compartment, many codes limit the flow to:

• a.1.5 gpm
• b.2.5 gpm combined for the compartment✓
• c.2.0 gpm
• d.5.0 gpm

The model-code maximum is 2.5 gpm per showerhead at 80 psi, and many adopted codes limit the combined flow of all heads serving one compartment to 2.5 gpm as well, so confirm the adopted code. Treating each head as a separate 2.5 gpm allowance can exceed the limit.

What is the minimum drain size for a commercial food-waste grinder (disposer)?

• a.2 in✓
• b.1-1/4 in
• c.1-1/2 in
• d.3 in

A commercial food-waste grinder requires a minimum 2 in drain and trap because of the volume and character of its discharge (IPC 704 / manufacturer listing). 1-1/2 in serves a residential disposer, and 1-1/4 in is far too small.

What is the minimum drain size for a residential food-waste grinder (disposer)?

• a.1-1/2 in✓
• b.3 in
• c.2 in
• d.1-1/4 in

A residential disposer discharges through the kitchen-sink drain and requires a minimum 1-1/2 in drain and trap. 1-1/4 in is the lavatory minimum and is undersized for a disposer, while 2 in is the commercial-grinder minimum.

What is the minimum trap and drain size for a bathtub?

• a.3 in
• b.1-1/4 in
• c.2 in
• d.1-1/2 in✓

A bathtub requires a minimum 1-1/2 in trap and drain (IPC Table 709.1). 1-1/4 in is the lavatory minimum and is undersized for a tub, and 2 in or 3 in exceeds what a tub requires.

An emergency eyewash or drench shower for worker safety must deliver tepid water in what temperature range?

• a.32 to 50 degrees F
• b.About 140 degrees F
• c.110 to 120 degrees F
• d.60 to 100 degrees F✓

Emergency eyewash and shower equipment must deliver tepid flushing fluid, generally 60 to 100 degrees F (ANSI/ISEA Z358.1), so a victim can tolerate a full flush without cold shock or scalding. 110 degrees and above is a scald risk and near-freezing water drives victims off the unit.

A bathtub trap and its waste-and-overflow concealed in a wall or floor must be provided with:

• a.No access, since it is concealed
• b.A wall that is cut open each time service is needed
• c.The overflow opening only
• d.An access panel or other approved access to the trap and waste✓

Concealed slip-joint connections such as a tub waste-and-overflow must remain accessible through an access panel or removable access so the joints can be serviced (IPC 405.8 / 712 access rules). Sealing them permanently behind finished construction is not permitted.

To control Legionella growth, stored hot water in a water heater is generally kept at a minimum of about:

• a.110 degrees F
• b.90 degrees F
• c.180 degrees F
• d.140 degrees F✓

Storing water at about 140 degrees F suppresses Legionella, while the water delivered to fixtures is tempered down (for example to 110 degrees F at public lavatories) with a mixing valve to prevent scalding. 90 and 110 degrees are within the range where the bacteria thrive.

A fuel-fired water heater installed in a bathroom or a bedroom must be:

• a.Any atmospheric-vented type
• b.Prohibited entirely
• c.Limited to an electric water heater only, because no gas-fired unit of any kind may ever be placed in a bedroom or bathroom
• d.A direct-vent or sealed-combustion type, or installed in a sealed enclosure with combustion air from outdoors✓

A fuel-burning water heater in a bedroom or bathroom must be a direct-vent unit or be enclosed in a sealed room that draws combustion air from outdoors, so occupants are not exposed to combustion products in a sleeping or bathing space (IFGC / IRC). An open atmospheric unit is not allowed there.