Acronyms and Abbreviations in Engineering Complied by Allan Wise, based in Australia ( 根据澳标)AA - AmpereA/C - Air ConditioningA/H - After HoursAB - As BuiltAEC - Architecture, Engineering, and ConstructionAFL - Above Floor LevelAFL - Above Finished LevelAG - Agricultural pipe drainAGL - Above Ground LevelAHD - Australian Height Datum AHU - Air Handler UnitAPPROX - ApproximatelyAS - Australian StandardASCII - American Standard Code for Information InterchangeATF - Along Top FlangeBB - Basin or BottomBLDG - BuildingBNS - Business Network Services BOT - BottomBQ - Bendable QualityBSP - British Standard Pipe LL - Steel AngleLAN - Local Area NetworkLGX - Line Group Cross (Connector, fibre optical cable)LH - Left HandLPG - Liquid Petroleum GasLT - Laundry TroughMm - Metres (English) or MetersMAX - MaximumMDF - Main Distribution Frame (Telecommunications)MFR - ManufacturerMHz - MegahertzMicky Mouse - A toy project, of very low quality.MIN - MinimumMISC - MiscellaneousM.J. - Movement Jointmm - MillimetresMS - Mild SteelNNC - Normally ClosedNET - NetworkBT - Bath TubBT - Boundary TrapBTM - BottomBW - Both WaysCC - C shaped steel purlinC/C - Cross CentresC.J. - Control Joint (or Construction Joint) CAD - Computer Aided Design. Less commonly use is Computer Assisted Drafting.CCTV - Closed Circuit TeleVisionCFW - Continuous Fillet WeldCHS - Circular Hollow SectionCL - Center LineCLG - Control JointCLR - ClearanceCMU - Cement Masonry UnitCNJ - Construction JointCOL - ColumnCOMMS - CommunicationsCONN - ConnectionCONT - ContinuousCS - Cleaners SinkCT - ControllerCTR(S) - Centre/SCTRL - ControlCTRS - CentersCU - Dental Cuspidor No. - NumberNOM - NominalNS - Near SideN.S.O.P. - Not Shown On PlanNTS - Not To ScaleNZS - New Zealand StandardOOA or O/A - OverallOD - Outside DiameterOPT - OptionalPPCD - Pitch Circle DiameterPFC - Parallel Flange ChannelPL - PlatePT - Pressure TappingPVC - Ploy Vinyl ChlorideQQTY - QuantityRR - RadiusRAD - Radius or radialREF - ReferenceREINF - ReinforcementREQ'D - RequiredREV - RevisionRH - Right HandRHS - Rectangular Hollow Section RL - Reduced Level or Relative LevelCVR - Cover°C - Degrees CelsiusDDAR - Dressed All RoundDD - Design DrawingDIA - DiameterDIM - DimensionDN - Diameter NominalDP - Down PipeDR - DryerDW - DishwasherDWG - DrawingDWG(S) - Drawing/SEEA - Equal Angle (steel)EF - Each FaceEL - Elevated LevelEL - ElevationELEC - ElectricalEQ - EqualEQUIP - EquipmentEW - Each WayEWB - Electric Water BoilerEWC - Electric Water CoolerFFB - Footing BeamF'c - Characteristic Concrete Strength FCU - Fan Coil Unit SS - SinkSAN - SanitarySDU - Sanitary Disposal UnitSF - Strip FootingSHR - ShowerSHS - Square Hollow SectionSIM - SimilarSQ - SquareSS or S/S - Stainless SteelSL - Structural LevelSSL - Structural Slab LevelSTD - StandardTT - TopTB - Tie BeamTEMP - TemperatureTFC - Taper Flange ChannelTHK - ThickTO or T.O. or T.OFF - Top OffTR - Laundry TroughTUN - TundishTYP - TypicalUU/S - Under SideUA - Unequal Angle (steel)UB - Universal Beam (steel)UC - Universal Column (steel)UNO - Unless Noted Otherwise (UON isFFL - Finished Floor LevelFL - Floor LevelFOC - Fibre Optic CableFS - Far SideFSBL - Full Strength Butt WeldFTG - FootingFTP - Fibre Termination Panel (fibre optical cable)FW - Fillet WeldFWF - From Web Face (steel)GGALV - GalvanizedGCI - Galvanized corrugated iron.GIS - Graphic Information SystemGSM - Global System of Moblie or "Groupe Speciale Mobile" in FrenchHH - Prewash Hose ReelHOR - HorizontalHORIZ - HorizontalHP - High PressureHWB - Hair Wash BasinIID - Inside DiameterIE - Invert ElevationIL - Invert LevelIO - Inspection OpeningIP - Intersection PointISO - International Standard Organisation prefered)UON - Unless Otherwise NotedUR - UrinalVVER - VerticalVERT - VerticalWWAN - Wide Area NetworkWB - Welded Beam (steel)WC - Welded Column (steel)WC - Water Closet (toilet)WC(P) - Water Closet With 'P' TrapWC(S) - Water Closet With 'S' TrapWD - Working DrawingWM - Washing MachineWP - Water Proof or Work PointXX - By. Example, "N12 x 1200 long" also means "N12 by 1200 long".YZZ - Zulu (Greenwich Mean Time)Z - Z shaped steel purlinSpecial Characters°C = Degrees CelsiusØ = Diameter'# = Number。