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.