uniform mechanical code- 2009 chapter 2

8/14/2019 Uniform Mechanical Code- 2009 Chapter 2

1/10

201.0 General.

For the purpose of this code, certain abbreviations,terms, phrases, words, and their derivatives shall beconstrued as specified in this chapter. Words used inthe singular include the plural, and the plural thesingular. Words used in the masculine genderinclude the feminine, and the feminine the mascu-line.

202.0 Accepted Meanings.

Except as defined in this chapter or elsewhere in thiscode, the interpretation of words used in this codeshall be in accordance with the meanings defined inthe applicable building, electric, fire, or plumbingcode and Websters Third New International Dictionaryof the English Language, Unabridged , copyright 1993.

203.0 AABSORPTION UNIT An absorption refrigerationsystem that has been factory-assembled and testedprior to its installation.ACCESSIBLE Having access to but which firstshall be permitted to require the removal of an accesspanel, door, or similar obstruction covering the itemdescribed.ACCESSIBLE, READILY Capable of beingreached safely and quickly for operation, repair, orinspection without requiring those to whom readyaccess is requisite to climb over or remove obstacles,or to resort to the use of portable access equipment.AIR, COMBUSTION SeeCombustion Air .AIR, CONDITIONED Air that has been treated toachieve a desired level of temperature, humidity, orcleanliness.AIR, EXHAUST Air being removed from any spaceor piece of equipment and conveyed directly to theatmosphere by means of openings or ducts.AIR-HANDLING UNIT A blower or fan used for thepurpose of distributing supply air to a room, space,or area.AIR, MAKEUP Air that is provided to replace air being exhausted.AIR-MOVING SYSTEM A system designed toprovide heating, cooling, or ventilation in which oneor more air-handling units are used to supply air to acommon space or are drawing air from a commonplenum or space.

AIR, OUTSIDE Air from outside the buildingintentionally conveyed by openings or ducts torooms or to conditioning equipment.AIR, RETURN Air from the conditioned area that isreturned to the conditioning equipment for recondi-tioning.AIR, SUPPLY Air being conveyed to a conditionedarea through ducts or plenums from a heatexchanger of a heating, cooling, absorption, or evap-orative cooling system.APPLIANCE A device that utilizes fuel or otherforms of energy to produce light, heat, power, refrig-eration, or air-conditioning. This definition also shallinclude a vented decorative appliance.APPROVED Acceptable to the Authority Having Jurisdiction.APPROVED TESTING AGENCY An organizationprimarily established for purposes of testing toapproved standards and approved by the AuthorityHaving Jurisdiction. [UPC:203.0]ASSEMBLY BUILDING A building or a portion of a building used for the gathering together of fifty(50) or more persons for such purposes as delibera-tion, education, instruction, worship, entertainment,amusement, drinking, dining, or awaiting trans-portation.

AUTHORITY HAVING JURISDICTION The organi-zation, office, or individual responsible for enforcingthe requirements of a code or standard, or forapproving equipment, materials, installations, orprocedures. The Authority Having Jurisdiction shall be a federal, state, local, or other regional depart-ment or an individual such as a plumbing official,mechanical official, labor department official, healthdepartment official, building official, or othershaving statutory authority. In the absence of a statu-tory authority, the Authority Having Jurisdictionmay be some other responsible party. This definitionshall include the Authority Having Jurisdictionsduly authorized representative.AUTOMATIC That which provides a functionwithout the necessity of human intervention. [NFPA96:3.3.6]AZEOTROPE A refrigerant blend comprisingmultiple components of different volatiles that, whenused in refrigeration cycles, do not change volu-metric composition or saturation temperature as theyevaporate or condense at constant pressure.

11

CHAPTER 2DEFINITIONS


2/10

204.0 BBOILER, HIGH-PRESSURE A boiler furnishingsteam at pressures in excess of fifteen (15) poundsper square inch (103.4 kPa) or hot water at tempera-tures in excess of 250F (121C) or at pressures inexcess of one-hundred and sixty (160) pounds per

square inch (1,102.4 kPa).BOILER ROOM Any room containing a steam orhot water boiler.BONDING JUMPER A reliable conductor to ensurethe required electrical conductivity between metalparts required to be electrically connected. [NFPA70:100.1]BREATHING ZONE The region within an occupiedspace between three (3) planes three (3) and seventy-two (72) inches (75 and 1,800 mm) above the floorand more than two (2) feet (600 mm) from the wallsor fixed air-conditioning equipment. [ASHRAE62.1:3]BREATHING ZONE OUTDOOR AIRFLOW ( Vbz ) The rate of outdoor airflow required in the breathingzone of an occupiable space.BREECHING A metal connector for medium- andhigh-heat appliances.BTU/H The listed maximum capacity of any appli-ance, absorption unit, or burner expressed in Britishthermal units input per hour, unless otherwisenoted.BUILDING CODE The building code that isadopted by this jurisdiction.BUILDING OFFICIAL SeeAuthority Having Juris-diction .

205.0 CCAS NUMBER The Chemical Abstract Systemregistry number.CENTRAL HEATING PLANT or HEATING PLANT Environmental heating equipment installed in amanner to supply heat by means of ducts or pipes toareas other than the room or space in which theequipment is located.CERTIFIED A formally stated recognition andapproval of an acceptable level of competency,acceptable to the Authority Having Jurisdiction.[NFPA 96:3.3.9]CHIMNEY A vertical shaft enclosing one or moreflues for conveying flue gases to the outside atmo-sphere.

Factory-Built Chimney A listed chimney.Masonry Chimney A chimney of solid masonryunits, bricks, stones, listed masonry units, or rein-forced concrete, lined with suitable flue liners.

Metal Chimney A chimney constructed of metal with a minimum thickness not less thanone-hundred and twenty-seven one-hundredths(0.127) inch (3.23 mm) (No. 10 manufacturersstandard gauge) steel sheet.

CHIMNEY CLASSIFICATIONS:

Chimney, Residential Appliance-Type Afactory-built or masonry chimney suitable forremoving products of combustion from residen-tial-type appliances producing combustion gasesnot in excess of 1,000F (538C), measured at theappliance flue outlet. Factory-built Type HTchimneys have high-temperature thermal shock resistance.Chimney, Low-Heat Appliance-Type Afactory-built, masonry, or metal chimney suit-able for removing the products of combustionfrom fuel-burning low-heat appliancesproducing combustion gases not in excess of

1,000F (538C) under normal operating condi-tions, but capable of producing combustiongases of 1,400F (760C) during intermittentforced firing for periods up to one hour. Alltemperatures are measured at the appliance flueoutlet.Chimney, Medium-Heat Appliance-Type Afactory-built, masonry, or metal chimney suit-able for removing the products of combustionfrom fuel-burning medium-heat appliancesproducing combustion gases not in excess of 2,000F (1,093C), measured at the appliance flueoutlet.

Chimney, High-Heat Appliance-Type Afactory-built, masonry, or metal chimney suit-able for removing the products of combustionfrom fuel-burning high-heat appliancesproducing combustion gases in excess of 2,000F(1,093C), measured at the appliance flue outlet.

CHIMNEY CONNECTOR The pipe that connects afuel-burning appliance to a chimney.CLOSED COMBUSTION SOLID-FUEL-BURNINGAPPLIANCE A heat-producing appliance thatemploys a combustion chamber that has no openingsother than the flue collar, fuel-charging door, andadjustable openings provided to control the amountof combustion air that enters the combustionchamber.CLOSET SeeConfined Space .CLOTHES DRYER An appliance used to dry wetlaundry by means of heat derived from the combus-tion of fuel gases or electric heating elements.CLOTHES DRYER, TYPE 1 Primarily used infamily living environment. May or may not be coinoperated for public use. [NFPA 54:3.3.18.1]

UNIFORM MECHANICAL CODE

12

204.0 205.0


3/10

CLOTHES DRYER, TYPE 2 Used in business withdirect intercourse of the function with the public.May or may not be operated by public or hired atten-dant. May or may not be coin operated. [NFPA54:3.3.18.2]CODE A standard that is an extensive compilation

of provisions covering broad subject matter or that issuitable for adoption into law independently of othercodes and standards.COMBUSTION AIR The total amount of airprovided to the space that contains fuel-burningequipment. Includes air for fuel combustion, drafthood dilution, and ventilation of the equipmentenclosure.COMPRESSOR, POSITIVE DISPLACEMENT Acompressor in which increase in pressure is attained by changing the internal volume of the compressionchamber.COMPRESSOR, REFRIGERANT A machine, withor without accessories, for compressing a refrigerantvapor.CONDENSER The part of the system designed toliquefy refrigerant vapor by removal of heat.CONDENSING APPLIANCE An appliance thatcondenses part of the water vapor generated by the burning of hydrogen in fuels.CONDENSING UNIT A mechanical refrigerationsystem, consisting of one or more power-drivencompressors, condensers, liquid receivers if provided, and the regularly furnished accessoriesthat have been factory assembled and tested prior to

its installation.CONDITIONED SPACE An area, room, or spacenormally occupied and being heated or cooled forhuman habitation by any equipment.CONFINED SPACE A room or space having avolume less than fifty (50) cubic feet (1.42 m3) per1,000 Btu/h (293 W) of the aggregate input rating of all fuel-burning appliances installed in that space.COOLING Air cooling to provide a room or spacetemperature of 68F (20C) or above.COOLING SYSTEM All of that equipment,including associated refrigeration, intended orinstalled for the purpose of cooling air by mechanicalmeans and discharging such air into any room orspace. This definition shall not include any evapora-tive cooler.COOLING UNIT A self-contained refrigerationsystem that has been factory assembled, tested, andinstalled with or without conditioned air and ducts,without connecting any refrigerant-containing parts.This definition shall not include a portable coolingunit or an absorption unit.

CRAWL SPACE In a building, an area accessible by crawling, having a clearance less than humanheight, for access to plumbing or wiring, storage, etc.CSST An acronym for corrugated stainless steeltubing.

206.0 DDAMPERS shall be defined as follows:

Fire Damper An automatic-closing metalassembly consisting of one or more louvers, blades, slats, or vanes that closes upon detectionof heat so as to restrict the passage of flame andis listed to the applicable recognized standards.Smoke Damper A damper arranged to seal off airflow automatically through a part of an air ductsystem so as to restrict the passage of smoke andis listed to the applicable recognized standard.Volume Damper Any device that, wheninstalled, will restrict, retard, or direct the flow

of air in any duct, or the products of combustionin any heat-producing equipment, its ventconnector, vent, or chimney.

DESIGN FLOOD ELEVATION The elevation of thedesign flood, including wave height, relative to thedatum specified on the communitys legally desig-nated flood hazard map.DIRECT GAS-FIRED MAKEUP AIR HEATER Aheater in which all the products of combustiongenerated by the gas-burning device are releasedinto the outside airstream being heated.DIRECT VENT APPLIANCE An appliance that isconstructed and installed so that all air for combus-

tion is derived from the outside atmosphere and allflue gases are discharged to the outside atmosphere.DISTRICT HEATING PLANT A power boiler plantdesigned to distribute hot water or steam to userslocated off the premises.DRAFT HOOD A device built into an appliance ormade a part of the vent connector from an appliance,that is designed to:(1) Assure the ready escape of the flue gases in the

event of no draft, back draft, or stoppage beyondthe draft hood.

(2) Prevent a back draft from entering the appliance.(3) Neutralize the effect of stack action of the

chimney or gas vent upon the operation of theappliance.

DUCT Any tube or conduit for transmission of air,fumes, vapors, or dusts. This definition shall notinclude:(1) A vent, vent connector, or chimney connector.(2) Any tube or conduit wherein the pressure of the

air exceeds one (1) pound per square inch.(3) The air passages of listed self-contained systems.

DEFINITIONS 205.0 206.0

13


4/10

DUCT FURNACE A warm-air furnace normallyinstalled in an air-distribution duct to supply warmair for heating. This definition shall apply only to awarm-air heating appliance that depends for aircirculation on a blower not furnished as part of thefurnace.

DUCT SYSTEM Includes all ducts, duct fittings,plenums, and fans assembled to form a continuouspassageway for the distribution of air.DWELLING A building or portion thereof thatcontains not more than two dwelling units.DWELLING UNIT A building or portion thereof that contains living facilities, including provisionsfor sleeping, eating, cooking, and sanitation, asrequired by this code, for not more than one family.

207.0 E

ELECTRIC HEATING APPLIANCE A device thatproduces heat energy to create a warm environment by the application of electric power to resistanceelements, refrigerant compressors, or dissimilarmaterial junctions.ELECTRICAL CODE The National Electrical Codepromulgated by the National Fire Protection Associ-ation, as adopted by this jurisdiction.EQUIPMENT A general term including materials,fittings, devices, appliances, and apparatus used aspart of or in connection with installations regulated by this code.EVAPORATIVE COOLER A device used forreducing the sensible heat of air for cooling by theprocess of evaporation of water into an airstream.EVAPORATIVE COOLING SYSTEM All of thatequipment intended or installed for the purpose of environmental cooling by an evaporative cooler fromwhich the conditioned air is distributed throughducts or plenums to the conditioned area.EVAPORATOR That part of a refrigeration systemin which liquid refrigerant is vaporized to producerefrigeration.EXCESS FLOW VALVE (EFV) A valve designedto activate when the fuel gas passing through itexceeds a prescribed flow rate.

208.0 F

FIRE CODE The fire code adopted by this jurisdic-tion.FIREPLACE STOVE A chimney-connected,solid-fuel-burning stove (appliance) having part of its fire chamber open to the room.

FIRE-RESISTIVE CONSTRUCTION Constructioncomplying with the requirements of the BuildingCode for the time period specified.FLOOD HAZARD AREA The greater of thefollowing two areas:(1) The area within a floodplain subject to a 1

percent or greater chance of flooding in anygiven year.(2) The area designated as a flood hazard area on a

communitys flood hazard map, or otherwiselegally designated.

FLOOD HAZARD AREA SUBJECT TO HIGHVELOCITY WAVE ACTION Area within the floodhazard area that is subject to high-velocity waveaction, and shown on a Flood Insurance Rate Map orother flood hazard map as Zone V, VO, VE or V1-30.FLOOR FURNACE A completely self-containedfurnace suspended from the floor of the space beingheated, taking air for combustion from outside such

space and with means for observing flames andlighting the appliance from such space.FORCED-AIR-TYPE CENTRAL FURNACE Acentral furnace equipped with a fan or blower thatprovides the primary means for circulation of air.

Horizontal-Type Central Furnace A furnacedesigned for low-headroom installations withairflow through the appliance in a horizontalpath.Upflow-Type Central Furnace A furnacedesigned with airflow essentially in a verticalpath, discharging air at or near the top of thefurnace.

Downflow-Type Central Furnace A furnacedesigned with airflow essentially in a verticalpath, discharging air at or near the bottom of thefurnace.Enclosed Furnace A specific heating orheating and ventilating furnace incorporating anintegral total enclosure and using only outsideair for combustion.

FRACTIONATION A change in composition of a blend by preferential evaporation of the morevolatile component or condensation of the lessvolatile component.FUSIBLE PLUG A device arranged to relieve pres-sure by operation of a fusible member at a predeter-mined temperature.

209.0 GGALVANIZED STEEL Any steel conforming to therequirements of UMC Standard No. 2-2.GENERATOR A device equipped with a means of heating used in an absorption system to drive refrig-erant out of solution.


14

206.0 209.0


5/10

GRAVITY HEATING SYSTEM Any heating systemconsisting of a gravity-type warm-air furnace,together with all air ducts or pipes and accessoryapparatus installed in connection therewith.GRAVITY-TYPE WARM-AIR FURNACE A warm-air furnace depending primarily on circulation of air

through the furnace by gravity. This definition alsoshall include any furnace approved with a booster-type fan that does not materially restrict freecirculation of air through the furnace when the fan isnot in operation.GROUNDING ELECTRODE A conducting objectthrough which a direct connection to earth is estab-lished. [NFPA 70:100.1]

210.0 HHAZARDOUS LOCATION Any area or spacewhere combustible dust, ignitable fibers orflammable, volatile liquids, gases, vapors or mixturesare or may be present in the air in quantities suffi-cient to produce explosive or ignitable mixtures.HEAT (ENERGY) RECOVERY VENTILATOR Adevice intended to remove air from buildings,replace it with outside air, and in the process transferheat from the warmer to the colder airstreams.HEATING DEGREE DAY A unit, based upontemperature difference and time, used in estimatingfuel consumption and specifying nominal annualheating load of a building. For any one day when themean temperature is less than 65F (18C), there existas many degree days as there are Fahrenheit degrees

difference in temperature between mean tempera-ture for the day and 65F (18C).HEATING EQUIPMENT Includes all warm-airfurnaces, warm-air heaters, combustion productsvents, heating air-distribution ducts and fans, and allsteam and hot water piping, together with all controldevices and accessories installed as part of, or inconnection with, any environmental heating systemor appliance regulated by this code.HEATING SYSTEM A warm air heating plantconsisting of a heat exchanger enclosed in a casing,from which the heated air is distributed throughducts to various rooms and areas. A heating systemincludes the outside air, return air and supply airsystem, and all accessory apparatus and equipmentinstalled in connection therewith.HEAT PUMP A refrigeration system that extractsheat from one substance and transfers it to anotherportion of the same substance or to a second substanceat a higher temperature for a beneficial purpose.HIGH SIDE The parts of a refrigeration systemsubjected to approximately condenser pressure.

HOOD An air-intake device connected to amechanical exhaust system for collecting vapors,fumes, smoke, dust, steam, heat or odors from, at, ornear the equipment, place, or area where generated,produced, or released.

211.0 IIDLH (Immediately Dangerous to Life and Health) A concentration of airborne contaminant's, normallyexpressed in parts per million (ppm) or milligramsper cubic meter (mg/m 3), that represents themaximum level from which one could escape withinthirty (30) minutes without any escape-impairingsymptoms or irreversible health effects. This level isestablished by the National Institute of OccupationalSafety and Health (NIOSH).INDUSTRIAL HEATING EQUIPMENT Includesappliances, devices, or equipment used, or intendedto be used, in an industrial, manufacturing, orcommercial occupancy for applying heat to anymaterial being processed, but shall not include waterheaters, boilers, or portable equipment used by arti-sans in pursuit of a trade.INSANITARY LOCATION An area, space, or roomwhere the air is unfit or undesirable for circulation tooccupied parts of a building.

212.0 JJOINT, BRAZED Any joint obtained by joining of metal parts with alloys that melt at temperatureshigher than 840F (449C) but lower than the melting

temperature of the parts being joined.JOINT, COMPRESSION Any multipiece joint withcup-shaped threaded nuts that, when tightened,compress tapered sleeves so that they form a tight joint on the periphery of the tubing they connect.JOINT, FLANGED One made by bolting together apair of flanged ends.JOINT, FLARED Any metal-to-metal compression joint in which a conical spread is made on the end of a tube that is compressed by a flare nut against amating flare.JOINT, MECHANICAL General form for gastight

joints obtained by the joining of metal parts througha positive holding mechanical construction (such asflanged joint, screwed joint, or flared joint).JOINT, SOLDERED A joint made by the joining of metal parts with metallic mixtures or alloys that meltat a temperature up to and including 840F (449C).

213.0 KNo definitions.


15


6/10

214.0 LLABELED Equipment or materials bearing a labelof a listing agency (accredited conformity assessment body). See Listed (Third Par ty Cer ti f ied) .[UPC:214.0]LEL (Lower Explosive Limit) SeeLFL .

LFL (Lower Flammable Limit or Lower Limit ofFlammability) The minimum concentration of acombustible substance that is capable of propagatinga flame through homogeneous mixture of thecombustible and a gaseous oxidizer under the speci-fied condition of test. The LFL is sometimes referredto as LEL (Lower Explosive Limit). For the purposesof this definition, LFL and LEL are identical.LINE CONTACT INSTALLATION An installationin which a furnace is installed so that building joists,studs, or framing are contacted by the furnace jacketupon the lines formed by the intersection of the jacket sides with the top surface.

LIQUEFIED PETROLEUM GAS or LPG (LP Gas) Means and includes a material composed pre-domi-nantly of any of the following hydrocarbons ormixtures of them: propane, propylene, butane's(normal butane or isobutane), and butylenes. Whenreference is made to liquefied petroleum gas in thiscode, it shall refer to liquefied petroleum gases ineither the liquid or gaseous state.LISTED (THIRD PARTY CERTIFIED) Equipment ormaterials included in a list published by a listingagency (accredited conformity assessment body) thatmaintains periodic inspection on current production of listed equipment or materials and whose listing stateseither that the equipment or material complies withapproved standards or has been tested and found suit-able for use in a specified manner. [UPC:214.0]LISTING AGENCY An agency accredited by anindependent and authoritative conformity assess-ment body to operate a material and product listingand labeling (certification) system and that isaccepted by the Authority Having Jurisdiction,which is in the business of listing or labeling. Thesystem includes initial and ongoing product testing,a periodic inspection on current production of listed(certified) products, and that makes available apublished report of such listing in which specificinformation is included that the material or productconforms to applicable standards and found safe foruse in a specific manner. [UPC:214.0]LOW-PRESSURE HOT-WATER-HEATING BOILER A boiler furnishing hot water at pressures notexceeding 160 pounds per square inch (1,102.4 kPa)and at temperatures not exceeding 250F (121C).LOW-PRESSURE STEAM-HEATING BOILER A boiler furnishing steam at pressures not exceedingfifteen (15) pounds per square inch (103.4 kPa).

LOW SIDE Refers to the parts of a refrigerationsystem subjected to approximate evaporator pressure.

215.0 MMACHINERY The refrigeration equipment forminga part of the refrigeration system, including, but notlimited to, the following: compressors, condensers,liquid receivers, evaporators, and connecting piping.MANUFACTURER The company or organizationthat evidences its responsibility by affixing its name,trademark, or trade name to equipment or devices.MANUFACTURERS INSTALLATION INSTRUC-TIONS Printed instructions included with equip-ment or devices for the purpose of providing infor-mation regarding safe and proper installation and usewhether or not as part of the conditions of listing.

216.0 N

NONCOMBUSTIBLE As applied to buildingconstruction material, means a material that in theform in which it is used is either one of the following:(1) A material that, in the form in which it is used

and under the conditions anticipated, will notignite, burn, support combustion, or releaseflammable vapors when subjected to fire or heat.Materials that are reported as passing ASTM E136, Standard Test Method for Behavior of Materialsin a vertical Tube Furnace at 750, are considerednoncombustible material. [NFPA 220:3.3.4]

(2) Material having a structural base of noncombustible material as defined in 1 above, with asurfacing material not over one-eighth (1/8) inch(3.2 mm) thick that has a flame-spread index nothigher than fifty (50).Noncombustible does not apply to surface finish

materials. Material required to be noncombustiblefor reduced clearances to flues, heating appliances,or other sources of high temperature shall refer tomaterial conforming to 1 above. No material shall beclassed as noncombustible that is subject to increasein combustibility or flame-spread index beyond thelimits herein established, through the effects of age,moisture, or other atmospheric condition.

217.0 OOCCUPANCY The purpose for which a building orpart thereof is used or intended to be used.OCCUPANCY CLASSIFICATION Classificationsare defined in the Building Code.OCCUPIED SPACE An enclosed space intendedfor human activities excluding those spaces intendedprimarily for other purposes such as storage rooms


16

214.0 217.0


7/10

and equipment rooms that are only occupied occa-sionally and for short periods of time.

218.0 PPEL (Permissible Exposure Limit) The maximumpermitted eight-hour time-weighted average concen-tration of an airborne contaminant. The maximumpermitted time-weighted average exposures to beutilized are those published in 29 CFR 1910.1000.PEX An acronym for cross-linked polyethylene.PIPING The pipe or tube mains for interconnectingthe various parts of a system. Piping includes pipe,tube, flanges, bolting, gaskets, valves, fittings thepressure-containing parts of other components suchas expansion joints, strainers, and devices that servesuch purposes as mixing, separating, snubbing,distributing, metering, or controlling flow pipe-supporting fixtures and structural attachments.

PLENUM An air compartment or chamberincluding uninhabited crawl spaces areas above aceiling or below a floor, including air spaces belowraised floors of computer/data processing centers orattic spaces, to that one or more ducts are connectedand that forms part of either the supply-air, return-air or exhaust-air system, other than the occupiedspace being conditioned.PLUMBING CODE The Uniform Plumbing Codepromulgated by the International Association of Plumbing and Mechanical Officials, as adopted bythis jurisdiction.

PORTABLE COOLING UNIT A self-containedrefrigerating system, not over 3 horsepower rating,that has been factory assembled and tested, installedwithout supply-air ducts and without connectingany refrigerant-containing parts. This definition shallnot include an absorption unit.PORTABLE EVAPORATIVE COOLER An evapo-rative cooler that discharges the conditioned airdirectly into the conditioned area without the use of ducts and can be readily transported from place toplace without dismantling any portion thereof.PORTABLE HEATING APPLIANCE A heatingappliance designed for environmental heating thatmay have a self-contained fuel supply and is notsecured or attached to a building by any means otherthan by a factory-installed power supply cord.PORTABLE VENTILATING EQUIPMENT Venti-lating equipment that can be readily transportedfrom place to place without dismantling a portionthereof and that is not connected to a duct.POSITIVE DISPLACEMENT COMPRESSOR Acompressor in which increase in pressure is attained

by changing the internal volume of the compressionchamber.POWER BOILER PLANT One or more power steam boilers or power hot water boilers and connectingpiping and vessels within the same premises.PP An acronym for polypropylene.

PRESSURE, DESIGN The maximum workingpressure for which a specific part of a refrigerationsystem is designed.PRESSURE, FIELD TEST A test performed in thefield to prove system tightness.PRESSURE-IMPOSING ELEMENT A device orportion of the equipment used for the purpose of increasing the pressure of the refrigerant vapor.PRESSURE-LIMITING DEVICE A pressure-responsive mechanism designed to automaticallystop the operation of the pressure-imposing elementat a predetermined pressure.PRESSURE-RELIEF DEVICE A pressure-actuatedvalve or rupture member or fusible plug designed toautomatically relieve excessive pressure.PRESSURE TEST The minimum gauge pressureto which a specific system component is subjectedunder test condition.PRESSURE VESSEL REFRIGERANT A refrig-erant-containing receptacle that is a portion of a refrig-eration system, but shall not include evaporators,headers, or piping of certain limited size and capacity.

219.0 QQUALIFIED A competent and capable person orcompany that has met the requirements and trainingfor a given field acceptable to the Authority Having Jurisdiction. [NFPA 96:3.3.38]

220.0 RRADIANT HEATER A heater designed to transferheat primarily by direct radiation.RECEIVER, LIQUID A vessel permanentlyconnected to a refrigeration system by inlet andoutlet pipes for storage of liquid.REFRIGERANT SAFETY CLASSIFICATIONS Made up of a letter (A or B), that indicates the toxicity

class, followed by a number (1, 2, or 3), that indicatesthe flammability class. Refrigerant blends are simi-larly classified, based on the compositions at theirworst cases of fractionation, as separately determinedfor toxicity and flammability. In some cases, theworst case of fractionation is the original formulation.

TOXICITY Classes A and B signify refrigerantswith lower toxicity and higher toxicity,respectively, based on prescribed measures of chronic (long-term, repeated exposures) toxicity.


17


8/10

FLAMMABILITY Class 1 indicates refrigerantsthat do not show flame propagation in air whentested by prescribed methods at specified condi-tions. Classes 2 and 3 signify refrigerants withlower flammability and higher flammability, respectively. The distinction depends on both the Lower Flammability Limit (LFL) andheat of combustion.

REFRIGERATION MACHINERY ROOM A spacedesigned to safely house compressors and pressurevessels.REFRIGERATION ROOM or SPACE A room orspace in which an evaporator or brine coil is locatedfor the purpose of reducing or controlling the temper-ature within the room or space to below 68F (20C).REFRIGERATION SYSTEM, ABSORPTION Aheat-operated closed-refrigeration cycle in which asecondary fluid, the absorbent, absorbs a primaryfluid, the refrigerant, that has been vaporized in the

evaporator.REFRIGERATION SYSTEM, MECHANICAL Acombination of interconnected refrigerant-containingparts constituting one closed refrigerant circuit inwhich a refrigerant is circulated for the purpose of extracting heat and in which a compressor is usedfor compressing the refrigerant vapor.REFRIGERATION SYSTEM, SELF-CONTAINED A complete factory-assembled and tested system thatis shipped in one or more sections and has no refrig-erant-containing parts that are joined in the field byother than companion or block valves.RESIDENTIAL BUILDING A building or portionthereof designed or used for human habitation.RISER HEAT PIPE A duct that extends at an angleof more than forty-five (45) degrees (0.79 rad) fromthe horizontal. This definition shall not include any boot connection.ROOM HEATER A freestanding, nonrecessed,environmental heating appliance installed in thespace being heated and not connected to ducts.ROOM HEATER, UNVENTED An unvented, self-contained, freestanding, nonrecessed, fuel-gas burning appliance for furnishing warm air bygravity or fan circulation to the space in which

installed, directly from the heater without ductconnection. [NFPA 54:3.3.55.6]ROOM LARGE IN COMPARISON WITH SIZE OFEQUIPMENT A room having a volume of at leasttwelve (12) times the total volume of a furnace orair-conditioning appliance and at least sixteen (16)times the total volume of a boiler. Total volume of the appliance is determined from exterior dimen-sions and includes fan compartments and burnervestibules when used. When the actual ceiling height

of a room is greater than eight (8) feet (2,438 mm),the volume of the room is figured on the basis of aceiling height of eight (8) feet (2,438 mm).RUPTURE MEMBER A pressure-relief device thatoperates by the rupture of a diaphragm within thedevice on a rise to a predetermined pressure.

221.0 SSEAM, WELDED SeeJoint, Welded.SELF-CONTAINED Having all essential workingparts, except energy and control connections, socontained in a case or framework that they do notdepend on appliances or fastenings outside of themachine.SHAFT An interior space enclosed by walls orconstruction extending through one or more storiesor basements that connects openings in successivefloors, or floors and roof, to accommodate elevators,dumbwaiters, mechanical equipment, or similardevices to transmit light or ventilation air.SHAFT ENCLOSURE The walls or constructionforming the boundaries of a shaft.SHALL Indicates a mandatory requirement.SHOULD Indicates a recommendation or thatwhich is advised but not required.SMOKE DETECTOR An approved device thatsenses visible or invisible particles of combustion.STANDARD A document, the main text of whichcontains only mandatory provisions using the wordshall to indicate requirements and that is in a formgenerally suitable for mandatory reference by

another standard or code or for adoption into law.Nonmandatory provisions shall be located in anappendix, footnote, or fine-print note and are not to be considered a part of the requirements of a stan-dard.STATIONARY FUEL CELL POWER PLANT Aself-contained package or factory-matched packagesthat constitute an automatically operated assemblyof integrated systems for generating useful electricalenergy and recoverable energy that is permanentlyconnected and fixed in place.STRENGTH, ULTIMATE The highest stress levelthat the component can tolerate without rupture.SYSTEM OUTDOOR AIRFLOW ( Vot ) The rate of outdoor airflow required at the ventilation systemoutdoor air intake.

222.0 TTRAINED A person who has become proficient inperforming a skill reliably and safely through instruc-tion and practice/field experience acceptable to theAuthority Having Jurisdiction. [NFPA 96:3.3.48]


18

220.0 222.0


9/10

223.0 UUNIT HEATER A heating appliance designed fornonresidential space heating and equipped with anintegral means for circulation of air.UNUSUALLY TIGHT CONSTRUCTION is construc-tion where:

(1) Walls and ceilings exposed to the outside atmo-sphere have a continuous water vapor retarderwith a rating of one (1) perm or less with anyopenings gasketed or sealed;

(2) Weatherstripping is on openable windows anddoors; and

(3) Caulking or sealants are applied to areas such as joints around window and door frames, betweensole plates and floors, between wall-ceiling joints, between wall panels, and at penetrationsfor plumbing, electrical, and gas lines and atother openings.

224.0 VVALVE, PRESSURE-RELIEF A pressure-actuatedvalve held closed by a spring or other means anddesigned to automatically relieve pressure in excessof its setting; also called a safety valve.VALVE, STOP A device in a piping system to shutoff the flow of the fluid.VALVE, THREEWAYTYPE STOP A manuallyoperated valve with one inlet that alternately canstop flow to either of two outlets.VALVES, COMPANION OR BLOCK Pairs of mating stop valves valving off sections of refrigera-tion systems and arranged so that these sections may be joined before opening these valves or separatedafter closing them.VENT A listed factory-made vent pipe and ventfittings for conveying flue gases to the outside atmo-sphere.

Type B Gas Vent A factory-made gas ventlisted by a nationally recognized testing agencyfor venting listed or approved appliancesequipped to burn only gas.Type BW Gas Vent A factory-made gas ventlisted by a nationally recognized testing agencyfor venting listed or approved gas-fired ventedwall furnaces.Type L A venting system consisting of listedvent piping and fittings for use with oil-burningappliances listed for use with Type L or withlisted gas appliances.

VENT CONNECTOR, GAS That portion of agas-venting system that connects a listed gas appli-ance to a gas vent and is installed within the space orarea in which the appliance is located.

VENTED APPLIANCE CATEGORIESCategory I An appliance that operates with anonpositive vent static pressure and with a ventgas temperature that avoids excessive conden-sate production in the vent.Category II An appliance that operates with anon-positive vent static pressure and with a ventgas temperature that may cause excessivecondensate production in the vent.Category III An appliance that operates with apositive vent static pressure and with a vent gastemperature that avoids excessive condensateproduction in the vent.Category IV An appliance that operates with apositive vent static pressure and with a vent gastemperature that may cause excessive conden-sate production in the vent.

VENTED DECORATIVE APPLIANCE A ventedappliance whose only function is providing anaesthetic effect of flames.VENTED WALL FURNACE A vented environ-mental heating appliance designed for incorporationin, or permanent attachment to, a wall, floor, ceiling,or partition and arranged to furnish heated air bygravity or by a fan. This definition shall not includefloor furnaces, unit heaters, and room heaters.VENTILATING CEILING A suspended ceilingcontaining many small apertures through which air,at low pressure, is forced downward from an over-head plenum dimensioned by the concealed space between the suspended ceiling and the floor or roof

above.VENTILATION SYSTEM All of that equipmentintended or installed for the purpose of supplying airto, or removing air from, any room or space bymechanical means, other than equipment that is aportion of an environmental heating, cooling,absorption, or evaporative cooling system.VENTING COLLAR The outlet opening of an appli-ance provided for connection of the vent system.VENTING SYSTEM The vent or chimney and itsconnectors, assembled to form a continuous openpassageway from an appliance to the outside atmo-sphere for the purpose of removing products of combustion. This definition also shall include a ventingassembly that is an integral part of an appliance.VENTING SYSTEMGRAVITY-TYPE A systemthat depends entirely on the heat from the fuel beingused to provide the energy required to vent an appli-ance.VENTING SYSTEMPOWER-TYPE A systemthat depends on a mechanical device to provide apositive draft within the venting system.


19


10/10

VOLUME, INTERNAL GROSS The volume asdetermined from internal dimensions of thecontainer, with no allowance for the volume of theinternal parts.

225.0 W

WALL HEATER SeeVented Wall Furnace.WARM AIR FURNACE An environmental heatingappliance designed or arranged to discharge heatedair through any duct or ducts. This definition shallnot include a unit heater.WATER HEATER or HOT-WATER-HEATINGBOILER An appliance designed primarily tosupply hot water and equipped with automaticcontrols limiting water temperature to a maximumof 210F (99C).

226.0 X

No definitions.

227.0 YNo definitions.

228.0 ZZEOTROPE A blend comprising multiple compo-nents of different volatiles that, when used in refrig-eration cycles, change volumetric composition andsaturation temperatures as they evaporate orcondense at constant pressure.


20

224.0 228.0

uniform mechanical code- 2009 chapter 2

Documents