IAPMO PPE flashcards

32 cards. Read the term and the definition here. The deck at the top of this page is optional.

Uniform Plumbing Code

IAPMO's model plumbing code establishing minimum requirements for plumbing installation, adopted with local amendments by the authority having jurisdiction in each jurisdiction.

Authority having jurisdiction

The official or agency responsible for enforcing the plumbing code, approving installations, issuing permits, and interpreting code provisions where the text is silent.

Rough-in inspection

Inspection performed after piping is installed and tested but before it is concealed by walls, floors, or ceilings, verifying code compliance of drains, vents, and water lines.

Listed fixture

A fixture or device evaluated by an approved testing agency and bearing its label, confirming compliance with recognized standards for the intended installation.

Plumbing permit

Official authorization required before installing, altering, or repairing a plumbing system; exempt work is defined in the code's administrative provisions.

Code edition in force

The specific published edition of the model code that a jurisdiction has formally adopted, which may differ from the most recently published edition.

Existing installation

Plumbing lawfully installed under a prior code edition, generally permitted to remain unless the code or authority having jurisdiction requires upgrade.

Fixture unit

A dimensionless measure of probable load a fixture places on the plumbing system, used to size both water supply and drainage piping.

Drainage slope

Required fall per unit length of horizontal drain; commonly one-quarter inch per foot for 2-inch pipe and one-eighth inch per foot for 3-inch pipe.

Trap arm length

Maximum distance from the trap weir to the vent connection, limited by pipe diameter per code tables to prevent self-siphonage of the trap.

Vent stack sizing

Determination of vent pipe diameter based on drainage fixture units connected and stack length, using code tables to ensure adequate air flow.

Closet flange rough-in

Distance from the finished wall to the center of the closet flange, commonly 12 inches, used to position the water closet drain correctly.

Sanitary tee restriction

A sanitary tee may connect a vertical drain to a horizontal branch but cannot be used where flow changes from horizontal to horizontal or horizontal to vertical drainage.

T&P relief valve

Temperature and pressure relief valve on a water heater, piped full size to a safe discharge location without traps, reductions, or uphill runs.

Thermal expansion tank

Device installed in a closed water system to absorb water expansion from heating, preventing excessive pressure buildup and protecting piping and fixtures.

Residual pressure

Water pressure measured while water is flowing; the code sets a minimum at fixtures during peak demand, commonly 8 psi.

Static pressure

Water pressure measured with no flow occurring, reflecting elevation and supply pressure without friction losses in the piping system.

Probable demand

Estimated peak water flow in gallons per minute derived from total supply fixture units using code tables, used to size water service and distribution piping.

Velocity limit

Maximum allowable water velocity in piping, typically about 8 feet per second cold and 5 feet per second hot, to limit noise and erosion.

Building drain sizing

Selection of drain pipe diameter based on total drainage fixture units and available slope, using code tables for horizontal drainage piping.

Storm drainage sizing

Sizing of roof drains and storm piping based on roof area and local rainfall intensity, kept separate from the sanitary drainage system.

Water hammer arrestor

Device installed near quick-closing valves to absorb pressure surges, preventing pipe noise and damage from sudden flow stoppage.

Backwater valve

Device installed on a drainage line to prevent sewage from reversing into a building, required where fixtures are below the upstream manhole elevation.

Cross-connection

Any actual or potential connection between potable water piping and a source of contamination or pollution that could allow backflow into the drinking water supply.

Air gap

Unobstructed vertical separation between a water supply outlet and the flood level rim of a receptor; the only absolute protection against backflow.

Backsiphonage

Backflow caused by negative or reduced pressure in the supply piping, drawing contaminated liquid into the potable water system.

Backpressure

Backflow caused when downstream pressure exceeds the supply pressure, forcing nonpotable liquid into the potable water system.

RPZ assembly

Reduced pressure zone backflow assembly providing protection against both backsiphonage and backpressure at high hazard, with test cocks and shutoff valves.

Double check assembly

Backflow assembly with two check valves providing protection against backsiphonage and backpressure at low hazard only, not high hazard.

Pressure vacuum breaker

Backflow device protecting against backsiphonage only, installed at least 12 inches above the highest downstream outlet and not subject to backpressure.

Atmospheric vacuum breaker

Backflow device protecting against backsiphonage only, installed at least 6 inches above the highest downstream point and not under continuous pressure.

Annual backflow testing

Requirement for certified testers to verify performance of reduced pressure and double check assemblies yearly, with results reported to the water authority.