1、04-11 23 31 00 - 1 SECTION 23 31 00 HVAC DUCTS AND CASINGS SPEC WRITER NOTES: 1. Delete between /-/ if not applicable to project. Also delete any other item or paragraph not applicable in the section and renumber the paragraphs. 2. References to pressure in this section are gage pressure unless othe
2、rwise noted. PART 1 - GENERAL 1.1 DESCRIPTION A. Ductwork and accessories for HVAC including the following: 1. Supply air, return air, outside air, exhaust, make-up air, and relief systems. 2. Exhaust duct with HEPA filters for / Autopsy Suite / Negative Pressure Isolation Room / Biological Safety C
3、abinets / Radioisotope Hoods /. 3. Exhaust duct for chemical fume hoods, kitchen hood exhaust (grease) and “wet exhaust” ducts. B. Definitions: 1. SMACNA Standards as used in this specification means the HVAC Duct Construction Standards, Metal and Flexible. 2. Seal or Sealing: Use of liquid or masti
4、c sealant, with or without compatible tape overlay, or gasketing of flanged joints, to keep air leakage at duct joints, seams and connections to an acceptable minimum. 3. Duct Pressure Classification: SMACNA HVAC Duct Construction Standards, Metal and Flexible. 4. Exposed Duct: Exposed to view in a
5、finished room, / exposed to weather. / 1.2 RELATED WORK A. Fire Stopping Material: Section 07 84 00, FIRESTOPPING. B. Outdoor and Exhaust Louvers: Section 08 90 00, LOUVERS and VENTS. C. Kitchen Hoods: Section 23 38 13, COMMERCIAL-KITCHEN HOODS. D. Fume Hoods: Section 11 53 13, LABORATORY FUME HOODS
6、. /E. Seismic Reinforcing: Section 13 05 41, SEISMIC RESTRAINT REQUIREMENTS FOR NON-STRUCTURAL COMPONENTS./ F. General Mechanical Requirements: Section 23 05 11, COMMON WORK RESULTS FOR HVAC and STEAM GENERATION. G. Noise Level Requirements: Section 23 05 41, NOISE AND VIBRATION CONTROL FOR HVAC PIP
7、ING and EQUIPMENT. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-04-11 23 31 00 - 2 H. Duct Insulation: Section 23 07 11, HVAC, PLUMBING, and BOILER PLANT INSULATION I. Plumbing Connections: Section 22 11 00, FACILITY WATER DISTRIBUTION J. Air Flow
8、 Control Valves and Terminal Units: Section 23 36 00, AIR TERMINAL UNITS. K. Duct Mounted Coils: Section 23 82 16, AIR COILS. L. Supply Air Fans: Section 23 73 00, INDOOR CENTRAL-STATION AIR-HANDLING UNITS. M. Return Air and Exhaust Air Fans: Section 23 34 00, HVAC FANS. N. Air Filters and Filters E
9、fficiencies: Section 23 40 00, HVAC AIR CLEANING DEVICES. O. Duct Mounted Instrumentation: Section 23 09 23, DIRECT-DIGITAL CONTROL SYSTEM FOR HVAC. P. Testing and Balancing of Air Flows: Section 23 05 93, TESTING, ADJUSTING, and BALANCING FOR HVAC. Q. Smoke Detectors: Section 28 31 00, FIRE DETECTI
10、ON and ALARM. 1.3 QUALITY ASSURANCE A. Refer to article, QUALITY ASSURANCE, in Section 23 05 11, COMMON WORK RESULTS FOR HVAC and STEAM GENERATION. B. Fire Safety Code: Comply with NFPA 90A. C. Duct System Construction and Installation: Referenced SMACNA Standards are the minimum acceptable quality.
11、 D. Duct Sealing, Air Leakage Criteria, and Air Leakage Tests: Ducts shall be sealed as per duct sealing requirements of SMACNA HVAC Air Duct Leakage Test Manual for duct pressure classes shown on the drawings. E. Duct accessories exposed to the air stream, such as dampers of all types (except smoke
12、 dampers) and access openings, shall be of the same material as the duct or provide at least the same level of corrosion resistance. 1.4 SUBMITTALS A. Submit in accordance with Section 01 33 23, SHOP DRAWINGS, PRODUCT DATA, and SAMPLES. B. Manufacturers Literature and Data: 1. Rectangular ducts: a.
13、Schedules of duct systems, materials and selected SMACNA construction alternatives for joints, sealing, gage and reinforcement. b. Duct liner. c. Sealants and gaskets. d. Access doors. 2. Round and flat oval duct construction details: Provided by IHSNot for ResaleNo reproduction or networking permit
14、ted without license from IHS-,-,-04-11 23 31 00 - 3 a. Manufacturers details for duct fittings. b. Duct liner. c. Sealants and gaskets. d. Access sections. e. Installation instructions. 3. Volume dampers, back draft dampers. 4. Upper hanger attachments. 5. Fire dampers, fire doors, and smoke dampers
15、 with installation instructions. 6. Sound attenuators, including pressure drop and acoustic performance. 7. Flexible ducts and clamps, with manufacturers installation instructions. 8. Flexible connections. 9. Instrument test fittings. 10 Details and design analysis of alternate or optional duct syst
16、ems. 11 COMMON WORK RESULTS FOR HVAC and STEAM GENERATION. C. Coordination Drawings: Refer to article, SUBMITTALS, in Section 23 05 1.5 APPLICABLE PUBLICATIONS A. The publications listed below form a part of this specification to the extent referenced. The publications are referenced in the text by
17、the basic designation only. B. American Society of Civil Engineers (ASCE): ASCE7-05 . Minimum Design Loads for Buildings and Other Structures C. American Society for Testing and Materials (ASTM): A167-99(2009) Standard Specification for Stainless and Heat-Resisting Chromium-Nickel Steel Plate, Sheet
18、, and Strip A653-09 Standard Specification for Steel Sheet, Zinc-Coated (Galvanized) or Zinc-Iron Alloy coated (Galvannealed) by the Hot-Dip process A1011-09a Standard Specification for Steel, Sheet and Strip, Hot rolled, Carbon, structural, High-Strength Low-Alloy, High Strength Low-Alloy with Impr
19、oved Formability, and Ultra-High Strength B209-07 Standard Specification for Aluminum and Aluminum-Alloy Sheet and Plate C1071-05e1 . Standard Specification for Fibrous Glass Duct Lining Insulation (Thermal and Sound Absorbing Material) Provided by IHSNot for ResaleNo reproduction or networking perm
20、itted without license from IHS-,-,-04-11 23 31 00 - 4 E84-09a Standard Test Method for Surface Burning Characteristics of Building Materials D. National Fire Protection Association (NFPA): 90A-09 . Standard for the Installation of Air Conditioning and Ventilating Systems 96-08 Standard for Ventilati
21、on Control and Fire Protection of Commercial Cooking Operations E. Sheet Metal and Air Conditioning Contractors National Association (SMACNA): 2nd Edition 2005 . HVAC Duct Construction Standards, Metal and Flexible 1st Edition - 1985 . HVAC Air Duct Leakage Test Manual 6th Edition 2003 . Fibrous Gla
22、ss Duct Construction Standards F. Underwriters Laboratories, Inc. (UL): 181-08 . Factory-Made Air Ducts and Air Connectors 555-06 Standard for Fire Dampers 555S-06 . Standard for Smoke Dampers PART 2 - PRODUCTS SPEC WRITER NOTE: The following ductwork is not permitted: 1. Fibrous glass ductwork 2. U
23、nderground Ductwork 3. Concrete Ductwork 2.1 DUCT MATERIALS AND SEALANTS A. General: Except for systems specified otherwise, construct ducts, casings, and accessories of galvanized sheet steel, ASTM A653, coating G90; or, aluminum sheet, ASTM B209, alloy 1100, 3003 or 5052. B. Specified Corrosion Re
24、sistant Systems: Stainless steel sheet, ASTM A167, Class 302 or 304, Condition A (annealed) Finish No. 4 for exposed ducts and Finish No. 2B for concealed duct or ducts located in mechanical rooms. C. Optional Duct Materials: 1. Grease Duct: Double wall factory-built grease duct, UL labeled and comp
25、lying with NFPA 96 may be furnished in lieu of specified materials for kitchen and grill hood exhaust duct. Installation and accessories shall comply with the manufacturers catalog data. Outer jacket of exposed ductwork shall be stainless steel. Square and rectangular duct shown on the drawings will
26、 have to be converted to equivalent round size. D. Joint Sealing: Refer to SMACNA HVAC Duct Construction Standards, paragraph S1.9. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-04-11 23 31 00 - 5 1. Sealant: Elastomeric compound, gun or brush grad
27、e, maximum 25 flame spread and 50 smoke developed (dry state) compounded specifically for sealing ductwork as recommended by the manufacturer. Generally provide liquid sealant, with or without compatible tape, for low clearance slip joints and heavy, permanently elastic, mastic type where clearances
28、 are larger. Oil base caulking and glazing compounds are not acceptable because they do not retain elasticity and bond. 2. Tape: Use only tape specifically designated by the sealant manufacturer and apply only over wet sealant. Pressure sensitive tape shall not be used on bare metal or on dry sealan
29、t. 3. Gaskets in Flanged Joints: Soft neoprene. E. Approved factory made joints may be used. 2.2 DUCT CONSTRUCTION AND INSTALLATION A. Regardless of the pressure classifications outlined in the SMACNA Standards, fabricate and seal the ductwork in accordance with the following pressure classification
30、s: B. Duct Pressure Classification: 0 to 50 mm (2 inch) 50 mm to 75 mm (2 inch to 3 inch) 75 mm to 100 mm (3 inch to 4 inch) Show pressure classifications on the floor plans. C. Seal Class: All ductwork shall receive Class A Seal SPEC WRITER NOTE: Duct specified to be stainless steel should be shown
31、 cross-hatched on the drawings. D. Operating Room/Cystoscopy Room Supply Air: All supply air ductwork on the downstream side of the terminal final HEPA filter serving an operating room or cystoscopy room shall be fabricated from welded stainless steel, including all components of the air distributio
32、n system up to and including the supply air outlet. E. Wet Air Exhaust Ducts and Accessories: Ducts for dishwashers, scullery hood, cart washers, manual cart washers, cage washers, steam sterilizer hoods and orthotics hoods shall be 1.3 mm (18 gage) stainless steel made liquid tight with continuous
33、external weld for all seams and joints. Provide neoprene gaskets at flanged connections. Where ducts are not self draining back to the equipment, provide low point drain pocket with copper drain pipe to sanitary sewer. Provide access door in side of duct at drain pockets. SPEC WRITER NOTE: Terminal
34、humidifiers shall be used only for special cases where a central humidifier cannot be utilized (In general, the humidifiers should be Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-04-11 23 31 00 - 6 located in the air handling unit). Terminal humid
35、ifiers shall not be used for the operating suite (including operating rooms and cystoscopy rooms). /F. Provide a welded stainless steel duct section for housing the duct-mounted terminal humidifiers. Ductwork shall be at least 3 feet long on the upstream side and 6 feet long on the downstream side.
36、Slope the ductwork against the direction of airflow and provide drain connections./ G. Kitchen and Grill Hood (Ventilator) Exhaust Ducts: Comply with NFPA 96. 1. Material: 1.6 mm (16 gage) steel sheet (black iron), ASTM A1011, or 1.3 mm (18 gage) stainless steel. Use stainless steel for exposed duct
37、 in occupied areas. See Optional Duct Materials. 2. Construction: Liquid tight with continuous external weld for all seams and joints. Where ducts are not self draining back to the equipment, provide low point drain pocket with copper drain pipe to sanitary sewer. Provide access doors or panels for
38、duct cleaning inside of horizontal duct at drain pockets, at 6 m (20 feet) intervals, and at each change of direction. 3. Access doors or panels shall be of the same material and thickness of the duct with gaskets and sealants that are rated 815 degrees C (1500 degrees F) and shall be grease-tight.
39、4. Grease Duct: Double-wall factory-built grease duct, UL labeled and complying with NFPA 96 may be furnished in lieu of specified materials for kitchen and grill hood exhaust. Installation and accessories shall comply with the manufacturers catalog data. Outer jacket of exposed ductwork shall be st
40、ainless steel. Square and rectangular duct shown in the drawings will have to be converted to equivalent round size. H. Radioisotope H3, Hood Exhaust and Associated Ductwork: 1.3 mm (18 gage) all welded stainless steel duct. I. Laboratory Hood, Exhaust and Associated Ductwork: 1.3 mm (18 gage) all w
41、elded Stainless steel. J. Biological Safety Cabinet, H12, Hood Exhaust and Associated Ductwork: 1.3 mm (18 gage) all welded stainless steel. K. Perchloric Acid H14, Hood Exhaust: 1.3 mm (18 gage) stainless steel, liquid tight welded construction. Provide water wash down system in the hood and all as
42、sociated ductwork to the exhaust air outlet. Coordinate the wash down system requirements with the specified hood. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-04-11 23 31 00 - 7 L. Duct for Negative Pressure Up to 750 Pa (3 inch W.G.): Provide fo
43、r exhaust duct between HEPA filters and exhaust fan inlet including systems for Autopsy Suite exhaust. 1. Round Duct: Galvanized steel, spiral lock seam construction with standard slip joints. 2. Rectangular Duct: Galvanized steel, minimum 1.0 mm (20 gage), Pittsburgh lock seam, companion angle join
44、ts 32 mm by 3.2 mm (1-1/4 by 1/8 inch) minimum at not more than 2.4 m (8 feet) spacing. Approved pre-manufactured joints are acceptable in lieu of companion angles. M. Round and Flat Oval Ducts: Furnish duct and fittings made by the same manufacturer to insure good fit of slip joints. When submitted
45、 and approved in advance, round and flat oval duct, with size converted on the basis of equal pressure drop, may be furnished in lieu of rectangular duct design shown on the drawings. 1. Elbows: Diameters 80 through 200 mm (3 through 8 inches) shall be two sections die stamped, all others shall be g
46、ored construction, maximum 18 degree angle, with all seams continuously welded or standing seam. Coat galvanized areas of fittings damaged by welding with corrosion resistant aluminum paint or galvanized repair compound. 2. Provide bell mouth, conical tees or taps, laterals, reducers, and other low
47、loss fittings as shown in SMACNA HVAC Duct Construction Standards. 3. Ribbed Duct Option: Lighter gage round/oval duct and fittings may be furnished provided certified tests indicating that the rigidity and performance is equivalent to SMACNA standard gage ducts are submitted. a. Ducts: Manufacturer
48、s published standard gage, G90 coating, spiral lock seam construction with an intermediate standing rib. b. Fittings: May be manufacturers standard as shown in published catalogs, fabricated by spot welding and bonding with neoprene base cement or machine formed seam in lieu of continuous welded sea
49、ms. 4. Provide flat side reinforcement of oval ducts as recommended by the manufacturer and SMACNA HVAC Duct Construction Standard S3.13. Because of high pressure loss, do not use internal tie-rod reinforcement unless approved by the Resident Engineer. N. VA Type A and B Canopy Hoods, Reagent Grade Water Treatment Room and Battery Charging Room Exhausts: Constructed of 1.3 mm (18 gage) stainle
