IAPMO UMC MPE study materials
IAPMO UMC MPE study resources

IAPMO UMC MPE flashcards

IAPMO UMC MPE · Build recall with a focused review session.

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

Authority having jurisdiction
The official or agency responsible for enforcing the code, approving materials and methods, interpreting provisions, and conducting inspections.
Permit requirement
Mechanical work requires a permit before installation or alteration; ordinary repairs generally do not, but the AHJ makes the final determination.
Alternate materials and methods
The AHJ may approve materials or methods not specifically named in the code when they are shown to be equivalent in quality, strength, and safety.
Concealed work inspection
Work that will be covered must be inspected and approved before concealment; covering unapproved work may require its removal for inspection.
Duct pressure class
A classification of duct construction based on operating static pressure; higher classes require heavier gauge metal and closer seam and reinforcement spacing.
Return air prohibition
Return air may not be drawn from bathrooms, kitchens, garages, closets, or furnace rooms because of odors, contaminants, or combustion appliance hazards.
Fire damper
A listed device installed in a duct penetration of a fire-rated assembly that closes on fire to maintain the fire-resistance rating of the assembly.
Flexible duct friction
Flexible duct has roughly two to three times the friction loss of rigid duct of equal diameter, so it must be fully extended and limited in length.
Category I appliance
A gas appliance that operates at non-positive vent pressure and produces flue gases that do not condense in the vent; it uses a listed Type B vent.
Confined space threshold
A space is confined when its volume is less than 50 cubic feet per 1,000 Btu/h of total appliance input, requiring dedicated combustion air openings.
Outdoor combustion air sizing
Vertical ducts require 1 square inch free area per 4,000 Btu/h; horizontal ducts require 1 square inch per 2,000 Btu/h of total input.
Type B vent clearance
Listed double-wall Type B vent requires a specified clearance from combustibles, commonly 1 inch, as stated in its listing and instructions.
Garage appliance elevation
In garages, ignition sources such as burners and pilots must be elevated at least 18 inches above the floor and protected from vehicle impact.
Condensate disposal
Condensate from cooling coils and condensing appliances must drain by gravity or an approved pump to an approved receptor, trapped and protected from freezing.
Clearance to combustibles
The minimum distance between an appliance or vent and a combustible surface, set by the listing and measured from the casing or listed spacing.
Service platform
Attic and crawl space appliances require a level service platform and an unobstructed passageway sized for inspection and maintenance access.
A2L refrigerant
A mildly flammable refrigerant classification requiring ignition-source controls, leak detection, and ventilation when the charge exceeds the allowable limit in a space.
Refrigerant concentration limit
The maximum refrigerant concentration allowed in an occupied space, expressed in pounds per 1,000 cubic feet or parts per million, based on safety group.
Nitrogen pressure test
Refrigerant piping is pressure-tested with dry nitrogen, never oxygen or air, to the specified test pressure, then evacuated to the required micron level.
Refrigerant relief discharge
Where pressure relief is required, relief piping must discharge to a safe location outside the building away from air intakes and occupied areas.
Expansion tank
A closed hydronic system requires an expansion tank to absorb the increased volume of heated water and maintain system pressure within safe limits.
Hydronic relief valve
Boilers and closed hydronic systems require a relief valve sized to the system capacity, with discharge terminating at a safe point of disposal.
Backflow protection
Where a hydronic system connects to a potable water supply, an approved backflow preventer or air gap must protect the water supply from cross-connection.
Glycol derating
Antifreeze solutions increase expansion volume and reduce heat transfer capacity, so system components and concentration must be selected and maintained accordingly.
Type I kitchen hood
A hood listed for grease-laden vapors from cooking appliances, requiring listed fire suppression and ducted outdoor exhaust.
Dryer exhaust duct
Clothes dryer exhaust ducts must be smooth, of the required diameter, limited in developed length, and terminate outdoors with a backdraft damper.
Outdoor air intake location
Intakes must be separated from exhaust outlets, plumbing vents, and contamination sources by the minimum distances set in the code.
Sediment trap
A trap installed downstream of the appliance shutoff valve, arranged to collect debris so it cannot enter the appliance gas controls.
Gas piping test
Gas piping is tested with air or inert gas at the code-specified pressure and duration, not exceeding the pressure rating of any connected component.
Appliance connector limits
Listed flexible gas connectors must be the correct length and must not pass through walls, floors, or ceilings.
Solar stagnation protection
Solar thermal systems must control overheating during stagnation with expansion capacity, relief devices, and a means to dissipate collected energy.
Solid-fuel venting
Solid-fuel appliances require a chimney or vent listed for solid fuel, with clearances to combustibles set by the listing and a carbon monoxide alarm.