USACE / NAVFAC / AFCESA / NASA UFGS-23 35 19.00 20 (July 2006)
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Preparing Activity: NAVFAC Superseding
UFGS-23 35 19.00 20 (April 2006)
UNIFIED FACILITIES GUIDE SPECIFICATIONS
References are in agreement with UMRL dated January 2009
SECTION 23 35 19.00 20
INDUSTRIAL VENTILATION AND EXHAUST
07/06
NOTE: This guide specification covers the requirements for blower and exhaust
systems for removal of flammable vapors including paint spraying residue, corrosive
fumes, dust, and stock conveying.
Edit this guide specification for project specific requirements by adding, deleting,
or revising text. For bracketed items, choose applicable items(s) or insert
appropriate information.
Remove information and requirements not required in respective project, whether
or not brackets are present.
Comments and suggestions on this guide specification are welcome and should
be directed to the technical proponent of the specification. A listing of technical
proponents, including their organization designation and telephone number, is
on the Internet.
Recommended changes to a UFGS should be submitted as a Criteria Change Request
(CCR).
NOTE: This guide specification also includes plastic duct systems for removal
of nonflammable corrosive fumes and vapors. Materials shall be selected by
the designer to suit project requirements. The system shall be designed in
accordance with NFPA 91. Ventilation and exhaust systems and components for
removal of smoke and grease laden vapors from commercial type cooking equipment
are covered in Section 11400N FOOD SERVICE EQUIPMENT and Section 15810N DUCTWORK
AND DUCTWORK ACCESSORIES. Laboratory fume hoods are covered in Section 11601
LABORATORY EQUIPMENT AND FUME HOODS. The design agency (EFD, OICC, PWC, etc.)
shall ensure review of the ventilation system design by the appropriate Naval
Medical Command (NAVMEDCOM) activity in accordance with NAVOSH requirements.
For high temperature applications, the designer must specify special fans and
duct material as required for the particular application.
NOTE: The following information shall be shown on the project drawings:
1. Arrangement plan and details for fans, ducts, and accessories.
2. Duct pressure classes or duct operating pressures. Design duct for maximum
negative pressure practical to accommodate improper operation or poor maintenance.
3. Equipment schedules.
4. Equipment foundations and supports.
5. Structural supports for ducts where required.
6. The design of industrial ventilation systems and the editing of this section
should be performed by professional engineers or industrial hygienists with
a sound knowledge of industrial ventilation. Design should conform to the ACGIH
2092; ANSI Z9.2, Fundamentals Governing the Design and Operation of Local Exhaust
Systems; AIHA Z9.3, Design, Construction and Ventilation of Spray Finishing
Operations; MIL-HDBK-1003/17, Industrial Ventilation Systems; and other references
as applicable. Fan arrangements should be selected to eliminate system effects
identified in ANSI/AMCA 201.
PART 1 GENERAL
1.1 REFERENCES
NOTE: This paragraph is used to list the publications cited in the text of
the guide specification. The publications are referred to in the text by basic
designation only and listed in this paragraph by organization, designation,
date, and title.
Use the Reference Wizard's Check Reference feature when you add a RID outside
of the Section's Reference Article to automatically place the reference in the
Reference Article. Also use the Reference Wizard's Check Reference feature
to update the issue dates.
References not used in the text will automatically be deleted from this section
of the project specification when you choose to reconcile references in the
publish print process.
The publications listed below form a part of this specification to the extent referenced. The publications are
referred to within the text by the basic designation only.
[AIR MOVEMENT AND CONTROL ASSOCIATION INTERNATIONAL (AMCA)AMCA 201(2002) Fans and SystemsAMCA 210(2007) Laboratory Methods of Testing Fans for Aerodynamic Performance RatingAMCA 211(2005) Certified Ratings Programme - Product Rating Manual for Air Fan PerformanceAMCA 300(2005) Reverberant Room Method for Sound Testing of FansAMCA 301(2005) Methods for Calculating Fan Sound Ratings from Laboratory Test DataAMCA 500-D(1998) Laboratory Methods of Testing Dampers for RatingAMCA 99(2003) Standards HandbookAMCA 99-0401(1986) Classifications for Spark Resistant ConstructionAMCA Licensed Products(Online) Directory of Products Licensed Under the AMCA International Certified Ratings Program][AIR-CONDITIONING, HEATING AND REFRIGERATION INSTITUTE (AHRI)AHRI 1060(2005) Performance Rating of Air-to-air Heat Exchangers for Energy Recovery Ventilation Heat Equipment][AMERICAN BEARING MANUFACTURERS ASSOCIATION (ABMA)ABMA 11(1990; R 1999) Load Ratings and Fatigue Life for Roller BearingsABMA 9(1990; R 2000) Load Ratings and Fatigue Life for Ball Bearings][AMERICAN CONFERENCE OF GOVERNMENTAL INDUSTRIAL HYGIENISTS (ACGIH)ACGIH-2092S(2004) Industrial Ventilation: A Manual of Recommended Practice][AMERICAN INSTITUTE OF STEEL CONSTRUCTION (AISC)AISC 360(2005) Specification for Structural Steel Buildings, with Commentary][AMERICAN SOCIETY OF HEATING, REFRIGERATING AND AIR-CONDITIONING ENGINEERS (ASHRAE)ASHRAE 52.2(2007; Addenda B 2008) Method of Testing General Ventilation Air-Cleaning Devices for Removal Efficiency by Particle SizeASHRAE 55(2004; Interpertation 1: 2005; Errata 2006; Interpertation 2:2007; Errata 2007; Addendas a & B 2008) Thermal Environmental Conditions for Human OccupancyASHRAE 62.1(2007; INT 2007; INT 2-15 2008; Errata 2008; Addenda a, b, e, f and h 2008) Ventilation for Acceptable Indoor Air Quality][AMERICAN WELDING SOCIETY (AWS)AWS D1.1/D1.1M(2008) Structural Welding Code - SteelAWS D1.3/D1.3M(2008; Errata 2008) Structural Welding Code - Sheet SteelAWS Z49.1(2005) Safety in Welding, Cutting and Allied Processes][ASTM INTERNATIONAL (ASTM)ASTM A 1011/A 1011M(2008) Standard Specification for Steel, Sheet, and Strip, Hot-Rolled, Carbon, Structural, High-Strength Low-Alloy and High-Strength Low-Alloy with Improved FormabilityASTM A 123/A 123M(2008) Standard Specification for Zinc (Hot-Dip Galvanized) Coatings on Iron and Steel ProductsASTM A 167(1999; R 2004) Standard Specification for Stainless and Heat-Resisting Chromium-Nickel Steel Plate, Sheet, and StripASTM A 36/A 36M(2008) Standard Specification for Carbon Structural SteelASTM A 653/A 653M(2008) Standard Specification for Steel Sheet, Zinc-Coated (Galvanized) or Zinc-Iron Alloy-Coated (Galvannealed) by the Hot-Dip ProcessASTM B 117(2007a) Standing Practice for Operating Salt Spray (Fog) ApparatusASTM B 152/B 152M(2006ae1) Standard Specification for Copper Sheet, Strip, Plate, and Rolled BarASTM C 582(2002) Contact-Molded Reinforced Thermosetting Plastic (RTP) Laminates for Corrosion-Resistant EquipmentASTM C 920(2008) Standard Specification for Elastomeric Joint SealantsASTM D 1330(2004) Rubber Sheet GasketsASTM D 1654(2008) Evaluation of Painted or Coated Specimens Subjected to Corrosive EnvironmentsASTM D 1927(1981; R 1988) Rigid Poly(Vinyl Chloride) Plastic SheetASTM D 2000(2008) Standard Classification System for Rubber Products in Automotive ApplicationsASTM D 2564(2004e1) Standard Specification for Solvent Cements for Poly(Vinyl Chloride) (PVC) Plastic Piping SystemsASTM D 2665(2008b) Standard Specification for Poly(Vinyl Chloride) (PVC) Plastic Drain, Waste, and Vent Pipe and FittingsASTM D 4167(1997; R 2007) Fiber-Reinforced Plastic Fans and Blowers][BAY AREA AIR QUALITY MANAGEMENT DISTRICT (Bay Area AQMD)Bay Area AQMD Rule 8-51(1992; R 2001) Adhesive and Sealant Products][NATIONAL ELECTRICAL MANUFACTURERS ASSOCIATION (NEMA)NEMA ICS 1(2000; R 2005; R 2008) Standard for Industrial Control and Systems General RequirementsNEMA ICS 2(2000; Errata 2002; R 2005; Errata 2006) Standard for Industrial Control and Systems: Controllers, Contractors, and Overload Relays Rated Not More than 2000 Volts AC or 750 Volts DC: Part 8 - Disconnect Devices for Use in Industrial Control EquipmentNEMA ICS 6(1993; R 2006) Standard for Industrial Controls and Systems EnclosuresNEMA MG 1(2007; Errata 2008) Standard for Motors and Generators][NATIONAL FIRE PROTECTION ASSOCIATION (NFPA)NFPA 65(1993) Processing and Finishing of AluminumNFPA 664(2006) Prevention of Fires and Explosions in Wood Processing and Woodworking FacilitiesNFPA 70(2007; AMD 1 2008) National Electrical Code - 2008 EditionNFPA 91(2004) Exhaust Systems for Air Conveying of Vapors, Gases, Mists and Noncombustible Particulate Solids][RUBBER MANUFACTURERS ASSOCIATION (RMA)RMA IP-20(1988) Drives Using Classical V-Belts and Sheaves Cross Sections, A, B, C, and DRMA IP-22(1991) Drives Using Narrow V-Belts and Sheaves][SHEET METAL AND AIR CONDITIONING CONTRACTORS' NATIONAL ASSOCIATION (SMACNA)SMACNA 1143(1985) HVAC Air Duct Leakage Test ManualSMACNA 1378(1995, 2nd Ed) Thermoplastic Duct (PVC) Construction ManualSMACNA 1403(1975, 1st Ed) Accepted Industry Practice for Industrial Duct ConstructionSMACNA 1520(1999, 2nd Ed) Round Industrial Duct Construction StandardsSMACNA 1922(1980; Errata 2004, 1st Ed) Rectangular Industrial Duct Construction Standards][SOUTH COAST AIR QUALITY MANAGEMENT DISTRICT (SCAQMD)SCAQMD Rule 1168(1989; R 2005) Adhesive and Sealant Applications][THE SOCIETY FOR PROTECTIVE COATINGS (SSPC)SSPC Paint 11(1992; E 2000) Paint Specification No. 11Red Iron Oxide, Zinc Chromate, Raw Linseed Oil and Alkyd PrimerSSPC Paint 20(2002; E 2004) Paint Specification No. 20 Zinc-Rich Coating Type I Inorganic and Type II OrganicSSPC SP 5(2007) White Metal Blast Cleaning][U.S. DEPARTMENT OF DEFENSE (DOD)MIL-DTL-12276(Rev E) Varnish, Phenolic, BakingMIL-P-21035(Rev B; Notice 2) Paint, High Zinc Dust Content, Galvanizing Repair (Metric)MIL-P-24441(Rev C; Supp 1; INT Am 1) Paint, Epoxy-PolyamideMIL-PRF-23236(Rev C) Coating Systems for Ship Structures][U.S. GENERAL SERVICES ADMINISTRATION (GSA)FS A-A-272(Rev A, Notice 2) Caulking CompoundsFS TT-S-001543(Rev A) Sealing Compound: Silicone Rubber Base (For Calking, Sealing, and Glazing in Buildings and Other Structures)][U.S. GREEN BUILDING COUNCIL (USGBC)LEED(2002; R 2005) Leadership in Energy and Environmental Design(tm) Green Building Rating System for New Construction (LEED-NC)][U.S. NATIONAL ARCHIVES AND RECORDS ADMINISTRATION (NARA)29 CFR 1910.219Mechanical Power Transmission Apparatus][UNDERWRITERS LABORATORIES (UL)UL 181(2005; Rev thru Oct 2008) Standard for Factory-Made Air Ducts and Air ConnectorsUL 214(1997; Rev thru Aug 2001) Tests for Flame-Propagation of Fabrics and FilmsUL 33(2003; Rev thru Sep 2005) Heat Responsive Links for Fire-Protection ServiceUL Bld Mat Dir(2008) Building Materials Directory]1.2 GENERAL REQUIREMENTS
1.2.1 SMACNA Duct Construction Manuals
The recommendations in the Sheet Metal and Air Conditioning Contractors' National Association (SMACNA) duct construction
manuals shall be considered mandatory requirements. Substitute the word "shall" for "should" in these manuals.
1.2.2 Fan Data
[For fans include fan curves or rating tables and derating factors.] Provide certified performance curves showing
total pressure, power, and mechanical efficiency versus flow rate of the operating density and fan speed. All
areas of unstable operation shall be indicated. For fans equipped with adjustable capacity controls such as
variable inlet or vaneaxial fans with adjustable blade settings, minimum and maximum performance shall be indicated
along with performance for fire intermediate settings.
1.2.3 Natural Ventilation
Evaluate natural ventilation for appropriate spaces, and design air distribution systems to operate in the same
direction as natural ventilation to reduce energy cost of pumping outdoor air.
1.2.4 Industrial Ventilation and Exhaust Systems
Submit drawings including fan installation drawings; duct systems [, including welding and vehicle exhaust];
supports and anchor location and load imposed.
1.2.5 Start-Up Tests
Submit start-up tests reports in accordance with the paragraph entitled "Testing, Adjusting and Balancing."
Submit final test report for [the] system[s] tested, describing all test apparatus, instrumentation calculations,
factors, flow coefficients, sound levels, and equipment data based on ACGIH-2092S recommended forms or reasonable
facsimiles thereof to suit project conditions. Adjustment and setting data shall be included in test report.
Submit sound level test reports for high noise level equipment.
1.2.6 Related Requirements
Conform to Section 23 03 00.00 20 BASIC MECHANICAL MATERIALS AND METHODS as well as additional requirements specified
herein.
1.3 SUBMITTALS
NOTE: Submittals must be limited to those necessary for adequate quality control.
The importance of an item in the project should be one of the primary factors
in determining if a submittal for the item should be required.
A “G” following a submittal item indicates that the submittal requires Government
approval. Some submittals are already marked with a “G”. Only delete an existing
“G” if the submittal item is not complex and can be reviewed through the Contractor’s
Quality Control system. Only add a “G” if the submittal is sufficiently important
or complex in context of the project.
For submittals requiring Government approval on Army projects, a code of up
to three characters within the submittal tags may be used following the "G"
designation to indicate the approving authority. Codes for Army projects using
the Resident Management System (RMS) are: "AE" for Architect-Engineer; "DO"
for District Office (Engineering Division or other organization in the District
Office); "AO" for Area Office; "RO" for Resident Office; and "PO" for Project
Office. Codes following the "G" typically are not used for Navy projects.
Submittal items not designated with a "G" are considered as being for information
only for Army projects and for Contractor Quality Control approval for Navy
projects.
Government approval is required for submittals with a "G" designation; submittals not having a "G" designation
are [for Contractor Quality Control approval.][for information only. When used, a designation following the
"G" designation identifies the office that will review the submittal for the Government.] The following shall
be submitted in accordance with Section 01 33 00 SUBMITTAL PROCEDURES:
SD-02 Shop Drawings
Industrial ventilation and exhaust systems; G
SD-03 Product Data
Fans; G
Dampers; G
Flexible connectors
Flexible duct; G
Gaskets
Protective coating materials
Sealants; (LEED)
[ Submit manufacturer's product data, indicating VOC content.]
Access ports; G
Damper regulators; G
Blast gates; G
Vibration isolators; G
Ductwork, Dust [and Fume] Collection
Steel ducts; G
Fiberglass ductwork; G
Thermoplastic ductwork; G
Submit documentation indicating percentage of post-industrial and post-consumer recycled content
per unit of product. Indicate relative dollar value of recycled content products to total dollar
value of products included in project.
Vehicle tail pipe exhaust system; G
Welding fume exhaust system; G
[Local/Regional Materials
Submit documentation indicating distance between manufacturing facility and the project site.
Indicate distance of raw material origin from the project site. Indicate relative dollar value
of local/regional materials to total dollar value of products included in project.]
SD-07 Certificates
Welding procedures; G
Welding test agenda; G
Welding test procedures; G
Welders' identification; G
Fiberglass fan servicer experience information; G
SD-06 Test Reports
Fan tests, including sound power level tests; G
Ventilation and exhaust system start-up tests; G
Sound level tests; G
SD-10 Operation and Maintenance Data
Fans, Data Package 2; G
Vehicle tail pipe exhaust system, Data Package 2; G
Welding fume exhaust system, Data Package 2; G
Industrial ventilation and exhaust systems, Data Package 2; G
Submit in accordance with Section 01 78 23 OPERATION AND MAINTENANCE DATA.
SD-11 Closeout Submittals
Posted operating instructions
Submit text of posted operating instructions for ventilation and exhaust systems.
1.4 QUALITY ASSURANCE
1.4.1 Welders' Identification
Submit a listing of the names and identification symbols to be used to identify the work performed by the welder
or welding operator who after completing a welded joint shall identify it as his work by applying his assigned
symbol for a permanent record.
1.4.2 Fiberglass Fan Servicer Experience Information
Submit text.
1.4.3 Qualified Personnel
Operations involving joining thermoplastic ductwork by solvent or hot gas and joining fiberglass ductwork by
laminating shall be performed by personnel certified by the manufacturer as qualified for the work.
1.4.4 Qualification of Welders
Qualify each welder or welding operator by tests using equipment, welding procedures and a base metal and electrode
or filler wire from the same compatible group number that will be encountered in the applicable welding test
procedures. Welders or welding operators who make acceptable procedure qualification test welds will be considered
performance qualified for the welding procedure used. Determine performance qualification in accordance with
AWS D1.1/D1.1M. Notify the Contracting Officer 24 hours in advance as to the time and place of tests [and wherever
practical perform the tests at the work site].
1.4.5 TAB Requirements
Requirements are specified in Section 23 05 93 TESTING, ADJUSTING AND BALANCING and Section 23 08 01.00 20 TESTING
INDUSTRIAL VENTILATION SYSTEMS.
1.5 ENVIRONMENTAL REQUIREMENTS
NOTE: Effective delivery and mixing of fresh air within a building contributes
to the following LEED credit: EQ2.
For proper Indoor Environmental Quality, maintain positive pressure within the building. Ventilation shall meet
or exceed ASHRAE 62.1 and all published addenda. Meet or exceed filter media efficiency as tested in accordance
with ASHRAE 52.2. Thermal comfort shall meet or exceed ASHRAE 55.
1.6 POSTED OPERATING INSTRUCTIONS
Provide for ventilation and exhaust system. In addition, permanently mark, drill, and pin as an integral part
of device, final adjustment and settings pursuant to testing, adjusting, and balancing.
1.7 SAFETY PRECAUTIONS
1.7.1 Guards and Screens
Provide metal personnel safety guards for normally accessible unducted fan inlets and discharges and moving power
transmission components in accordance with OSHA 29 CFR 1910.219.
1.7.2 Welding
Conform to AWS Z49.1 for safety in welding and cutting.
1.8 SUSTAINABLE DESIGN REQUIREMENTS
1.8.1 Local/Regional Materials
NOTE: Using local materials can help minimize transportation impacts, including
fossil fuel consumption, air pollution, and labor.
Use materials or products extracted, harvested, or recovered, as well as manufactured, within a [500][_____]
mile [800][_____] kilometer radius from the project site, if available from a minimum of three sources.
PART 2 PRODUCTS
2.1 FANS, GENERAL REQUIREMENTS FOR
2.1.1 General Performance, Component, and Other Requirements
Fans shall have certified performance ratings as evidenced by conformance to the requirements of AMCA 211, and
shall be listed in AMCA Licensed Products, or shall be currently eligible for such listing. Fans shall generally
be in accordance with AMCA 99 unless superseded by other requirements stated elsewhere herein. Determine performance
data for fans in accordance with AMCA 210. Select fans to minimize the exposure of personnel working in or occupying
the immediate installation area. The total sound power level of the fan tests shall not exceed 90 dBA when tested
per AMCA 300 and rated per AMCA 301, or it shall be provided with an appropriate attenuation device or devices.
Scheduled fan performance is the performance required under specified or indicated installation conditions with
specified or indicated accessories. The net installed air performance of the fan, with accessories/appurtenances
in place, shall be sufficient to meet the scheduled performance within the limits of the fan rating certification
tolerance. Affix the manufacturer's product identification nameplate to each unit. Apply additional requirements
for specific service or generic type or class of fan. If nonuniform air flow conditions are likely to be encountered,
contact the fan manufacturer to ensure that the fan is rated for the additional fan inlet and outlet effect.
Install fans to minimize fan system effect in accordance with AMCA 201. Fans shall be listed in the Directory
of Products licensed to use AMCA seal.
2.1.2 Bearings and Lubrication
NOTE: Sleeve type bearings should be specified or indicated on drawings where
low noise levels are required.
Precision anti-friction or sleeve type with provisions for self-alignment and for radial and thrust loads imposed
by the service. Provide water-cooled bearings where required for the service or recommended by the manufacturer.
2.1.2.1 Anti-friction Bearings
NOTE:
Continuous 8-hour service 20,000
Continuous 24-hour service 40,000
Continuous 24-hour service 80,000
(extreme reliability)
Constructed of steel alloys with a certified L-10 minimum rated life of [20,000] [40,000] [80,000] hours under
load conditions imposed by the service. Rated and selected in accordance with ABMA 9 and ABMA 11. Provide with
dust-tight seals suitable for environment and lubricant pressures encountered; cast ferrous metal housing, bolted-split
pillow block type where located within fan casings; grease lubricated with provisions to prevent overheating
due to excess lubricant; surface ball check type grease supply fittings. Provide manual or automatic grease
pressure relief fittings visible from normal maintenance locations. Include lubrication extension tubes where
necessary to facilitate safe maintenance during operation and fill tubes with lubricant prior to equipment operation.
Prelubricated, sealed, anti-friction bearings, which conform to above specified materials and L-10 life requirements,
may be provided for fans requiring less than 0.37 kW 1/2 horsepower.
2.1.2.2 Sleeve Bearings
Premounted, self-aligning, continuous oil supply, single or double ring lubricated, insert type, with suitable
provisions for shaft expansion and such thrust as may be imposed by service loads. Provide water cooling for
shaft surface speed exceeding 6.1 meters per second 1200 feet per minute. Provide each sleeve bearing with approximately
473 mL 16 ounce capacity constant level oiler and oil level gage. Include on sleeve bearing submittal data:
Bearing manufacturing source, type, lubricant, clearances, "L/D" ratio, antifriction metal, belt angle, shaft
speed, shaft critical speed, Brinell hardness at journal, and shaft surface finish at journal in micro-inches.
2.1.3 Motors and Motor Starters
NOTE: The motor control requirements should be coordinated with the Electrical
Section and will depend on field conditions. The following types of motor starters
should be used as a guide only. When electrical power circuits to which ventilation
and exhaust equipment are connected are heavily loaded, the full voltage across
the line starting may result in excessive voltage drop on the circuits.
Power (kW) Voltage Type Starter
Up to 5 1/2 208-230 Across-the-line magnetic
5 1/2 to 11 208-230 Across-the-line magnetic
part winding or wye
delta
11 to 22 3/8 460 Across-the-line
magnetic, part winding
or wye delta
Above 11 208-230 Part winding or wye
delta
Above 22 1/2 460 Part winding or wye delta
Motor H.P. Voltage Type Starter
Up to 7 1/2 208-230 Across-the-line magnetic
7 1/2 to 15 208-230 Across-the-line magnetic
part winding or wye
delta
15 to 30 460 Across-the-line
magnetic, part winding
or wye delta
Above 15 208-230 Part winding or wye
delta
Above 30 460 Part winding or wye delta
Conform to NEMA MG 1 and NEMA ICS 1 and NEMA ICS 2. Motors less than 3/4 kW 1 hp shall meet NEMA High Efficiency
requirements. Motors 3/4 kW 1 hp and larger shall meet NEMA Premium Efficiency requirements. Motors shall not
exceed 1800 rpm, unless otherwise indicated, and shall be variable-speed, [[open] [dripproof] enclosure] [totally
enclosed fan cooled] [explosion proof] type. Provide [manual] [magnetic-across-the-line] [reduced voltage] [part-winding]
[wye-delta] type motor starters with [general-purpose NEMA 1] [weather resistant NEMA 3R] [watertight NEMA 4]
[moisture and dusttight NEMA 12] enclosure in accordance with NEMA ICS 6. Provide single-phase motors with inherent
thermal overload protection with manual reset. Provide three-phase motors with thermal overload protection in
the control panel. Provide permanently lubricated or grease-lubricated ball or roller bearings; auxiliary lubrication
and relief fittings on outside of fan casing; arrange grease lines to minimize pressure on bearing seals. Motor
power shall not be less than brake power required with blades set at maximum pitch angle at any air delivery
from the indicated amount down to 50 percent thereof.
2.1.4 Guards and Screens
Construct guards and screens to provide, as applicable: required strength and clearance with minimal reduction
in free area at fan inlets and discharges; cooling; access panels for tachometer readings; ease of sectional
disassembly for maintenance and inspection functions where guard total weight exceeds 22.70 kg 50 pounds; weather
protection where components are weather exposed. Installed guards and screens shall not negate noise control
and vibration isolation provisions. [For burn protection, insulate surfaces when service temperatures exceed
60 degrees C 140 degrees F as part of work under Section 23 07 00 THERMAL INSULATION FOR MECHANICAL SYSTEMS.]
2.1.5 Power Transmission Components
2.1.5.1 Fan Drives
[Direct] [or] [V-belt] type as indicated. V-belt drives shall conform to RMA IP-20 and RMA IP-22. Drives shall
be applied in accordance with the manufacturer's published recommendations, unless specified otherwise. Base
power rating of a V-belt drive on maximum pitch diameter of sheaves. Provide classical belt section adjustable
sheave type, with a minimum service factor of 1.5 for drives with motors rated up to and including 22 kW 30 hp
. [Provide classical section or narrow section, fixed sheave or adjustable sheave type with a minimum 1.5 service
factor for drives with motors rated over 22 kW 30 hp.] [Provide at least two belts for drives with motors rated
one hp and above.]
2.1.5.2 Sheaves
Statically and dynamically balanced, machined cast ferrous metal or machined carbon steel, bushing type, secured
by key and keyway. Pitch diameter or fixed sheaves and adjustable sheaves, when adjusted to specified limits,
shall not be less than that recommended by NEMA MG 1. Select adjustable sheaves that provide the required operating
speed with the sheave set at midpoint of its adjustment range. The adjustment range for various size and type
belts shall be: 16 percent, minimum for Classical section belts; 12 percent, minimum for Narrow section belts.
[Belt deflection in adjustable sheave drives shall not exceed 1 1/2 degrees.] Provide companion sheaves for
adjustable sheave drives with wide groove spacing to match driving sheaves, except that standard fixed pitch
spacing may be used for all two-through-four groove drives whose center-to-center dimensions exceed the following:
"A" and "B" Section 406 mm 16 inches; "C" Section 635 mm 25 inches; "D" Section 914 mm 36 inches. Furnish endless,
static dissipating, oil-resistant, synthetic cloth or filament reinforced elastomer construction belts.
2.1.6 Special Construction for Hazardous Areas
2.1.6.1 Spark-Resistant
Construct [_____] [specified or indicated] units in accordance with AMCA 99-0401; Type [A] [B] [C]. Provide
[Type B] [or] [Type C] construction and electrical grounding of fan parts and grounding to building structure
where fume or vapor handling systems conforming to NFPA 91 are specified. Do not place bearings in the air stream.
2.1.6.2 Explosion Proof
Construct fans to AMCA 99-0401, Type [A] [B] [C] spark-resistant requirements where explosion-proof electrical
components are specified or indicated to conform to NFPA 70, Class [_____], Group [_____], Division [_____] requirements.
2.1.7 Protective Coating for Fans
Prepare and coat fans as follows: Replace bolts required to provide access or adjustment and normally threaded
into the coated surface with studs or bolts having heads continuously welded inside. Omit sharp edges, self-tapping
screws, and permanent threads protruding into the coated surface. Eliminate hairline cracks and sharp inside
corners by continuous welding, brazing, or filling with high melting point solder. Seal impeller hub to the
shaft. Construct housing split to use external throughbolts. Flange inlet and outlet and consider as fan interior.
Peen or grind welds smooth, and grind outside corners to approximately 1.60 mm 1/16 inch radius. Sandblast metal
surfaces to white metal in accordance with SSPC SP 5Coat interior surfaces of housing in contact with airstream,
including inlet, impeller and shaft, flange faces, shaft seal, [exterior surfaces of housing] [, and bearing
and motor pedestal]. Do not coat bearings, coupling, motor, drive, or other auxiliaries. [Prepare and coat
stainless steel shaft.] [Finish fan in accordance with the manufacturer's standard practice.] [Coat fan with
[phenolic] [epoxy] [_____].] [Coat fan as indicated.] Statically and dynamically balance the fan in two planes
after coating and finishing, and where material has been removed, refinish and rebalance the fan as specified
herein.
2.2 CENTRIFUGAL FANS
2.2.1 General Requirements for Centrifugal Fans
NOTE: See Section 15070, "Mechanical Sound, Vibration, and Seismic Control,"
for guidance given in guide specification technical notes. Definite requirements
should be specified in contract specification for bidders' information.
Provide fan of [forward-curved] [radial] [backward inclined] [airfoil] type blades with [manual] [or] [automatic
inlet vanes [as indicated]]. Arrange fans for indicated service, and construct for the applicable AMCA 99Class
pressure ratings as indicated for system design pressure and temperature. Fan shaft shall be solid steel, ground
and finished as required for the service, with first critical speed a minimum 25 percent higher than cataloged
fan speed. Select fan for maximum efficiency, minimum noise, and stability during all modes of system operation.
[Vibration isolation mountings shall be spring type and limit vibration transmissibility to a maximum [_____]
[5] percent of the unbalanced force at lowest equipment speed, unless otherwise specified or indicated.] Arrangement
and drives shall be as indicated.
2.2.2 Industrial Exhauster[s]
NOTE: Use industrial exhausters for high particulate loading applications.
Single-width, single-inlet type arranged for indicated service and constructed for duty at indicated system design
pressure and temperature not to exceed [66] [93] [177] [260] [371] degrees C [150] [200] [350] [500] [700] degrees
F. Continuously welded [carbon] [alloy] [copper bearing alloy] [Type [_____] [304L] [316L] stainless] [steel]
[[_____] alloy aluminum] scroll with required reinforcement, flanged inlet and outlet connections, [cone] inlet
[bolted] [welded] to scroll side sheet, threaded and plugged scroll drain, [quick] [or] [bolted] access door
with gasket; [Carbon] [alloy] [Type [_____] stainless] steel shaft, [fitted with] [heat slinger] [shaft seal]
[grease lubricated stuffing box]; continuously welded [carbon] [alloy] [copper bearing alloy] [Type [_____] [304L]
[316L] stainless] [steel] [_____ alloy aluminum] impeller assembly. [_____] [radial] [paddle type (open radial)]
[backplated paddle] type impeller blades [with inlet shroud]. [Provide protective coating of _____.] on fan
surfaces exposed to [air] [fume] [vapor] stream; [Motor shall be totally enclosed type.] Mount complete assembly
including motor, power transmission components, and guards on a common vibration isolation base with spring mountings
[conforming to requirements indicated].
2.2.3 Utility Set[s]
Single-width, single-inlet, nonoverloading scroll type. Scroll shall be [intermittently] [or] [continuously]
welded [carbon] [Type [304L] [316L] stainless] [steel] [_____ alloy aluminum] with required reinforcement, [flanged
inlet and outlet connections], streamline orifice inlet bolted [and gasketed] to scroll side sheet, [threaded
and] [plugged] [piped] [scroll drain,] [access door with gasket]. [Carbon] [Type [304] [316] stainless] [steel]
[monel] shaft finished as required [and fitted with] [heat slinger] [shaft seal] [grease lubricated stuffing
box]; welded [carbon] [Type [304L] [316L] stainless] [steel] [_____ alloy aluminum] impeller assembly; [backward
inclined] flat or single thickness airfoil type impeller blades. Provide protective coating of [_____] for [fan
surfaces exposed to [air] [fume] [vapor] stream and weather.] Motor and power transmission components shall
be enclosed in ventilated weathertight hood. [Discharge shall be fitted with an automatic gravity shutter constructed
from [specified stainless steel] [aluminum].] [Mount complete assembly from individual points of support on
rails and vibration isolated by double-rubber-in-shear mountings] [conforming to requirements indicated].
2.2.4 In-line Centrifugal Fans
Welded steel casings, centrifugal backward inclined blades, stationary discharge conversion vanes, internal and
external belt guards and adjustable motor mounts. Inlet and outlet connections for fan casings to duct work
and equipment casings, may be of the slip fit or flanged type. [Provide guards for discharges. Rate fans with
guards in place.] Air shall enter and leave the fan axially. Inlet shall be streamlined and conversion vanes
shall eliminate turbulence and provide smooth discharge air flow. Enclose fan bearings and drive shafts, and
isolate from the air stream. Fan bearings shall be mechanically sealed against dust and dirt and shall be self-aligning,
pillow block ball or roller type. Motor and drive shall be provided by fan manufacturer.
2.2.5 Fiberglass Centrifugal Fans
NOTE: Show intended service on drawing fan schedule or specify here. Revise
paragraph if special chemical or corrosion resistance is required in accordance
with manufacturer's recommendations.
ASTM D 4167. Construct of fire retardant fiberglass with a flame spread rating at least equal to or less than
that of the duct system. Housing and fan impeller shall be fiberglass. Shaft and fan support stand shall be
steel with protective coating. Provide exterior gel coat, coating, or paint with ultraviolet light inhibiting
properties for fans exposed to sunlight. Fiberglass fans shall be suitable for [the intended service.] [use in
[_____]]. Provide with flanged outlet [and inlet] connections, [threaded [and plugged]] scroll drain, bolted
access and inspection doors, and epoxy coated steel fan base and motor mount.
2.3 [VANEAXIAL] [TUBEAXIAL] FANS
Direct-connected with adjustable blade impeller or V-belt driven. When direct connected, fans shall be driven
by totally-enclosed, air-over (TEAO), flanged or end mounted motors. When belt-driven, provide internal and
external belt guards and adjustable motor mounts.
2.3.1 Fan Impeller Blades
Air-foil type [with stationary guide vanes], designed to provide the efficiency [and sound level] indicated.
In fan selection, consider and account for any losses due to the size of the motor in relation to the fan hub
diameter. Impeller blades of direct-driven fans shall be adjustable to permit varying performance over a range
of volume and pressure. Index the hub to facilitate setting the angle of the blades uniformly and accurately
from minimum to maximum angle; provide stops to avoid overloading motor. Furnish motor with the factory blade
maximum setting included in the fan nameplate data.
2.3.2 Fan Casings
Cylindrical, or welded steel construction, with flanged inlets and outlets. Assemble motor support [and guide
vanes] by welding. Provide casings with bolted or hinged access plates adequate for inspection and servicing
of internal parts.
2.4 BATHROOM AND KITCHEN FANS
NOTE: Quiet operation will increase the likelihood that occupants will use
fans.
Power used shall be a maximum of 13 watts for 50 cfm fans; 15 watts for 70 cfm fans; 17 watts for 90 cfm fans;
and 20 watts for 100 cfm fans. Noise levels shall not exceed 0.5 sones for 50 to 70 cfm fans; 1.0 sones for
90 cfm fans; and 1.5 sones for 100 cfm fans. Fan lights shall be compact fluorescent.
2.5 BASIC MATERIALS
2.5.1 Coated and Uncoated Carbon Steel Sheets, Plates, and Shapes
2.5.1.1 Mill Galvanized Steel Sheet
ASTM A 653/A 653M, lock forming quality, Coating G-90[, 204 degrees C 400 degrees F, maximum].
2.5.1.2 Mill Galvanized Steel Shapes
ASTM A 36/A 36M galvanized in accordance with [ASTM A 123/A 123M] [ASTM A 653/A 653M].
2.5.1.3 Uncoated (Black) Carbon Steel Sheet
ASTM A 1011/A 1011M.
2.5.1.4 Uncoated (Black) Carbon Steel Plates and Shapes
ASTM A 36/A 36M.
2.5.2 Corrosion Resistant (Stainless) Steel
ASTM A 167, Type 304L or Type 316L with mill finish, except as otherwise specified.
2.5.3 Corrosion Protection
Treat equipment fabricated from ferrous metals that do not have a zinc coating conforming to [ASTM A 123/A 123M
] [ASTM A 653/A 653M] for prevention of corrosion with a factory coating or paint system that will withstand
125 hours in a salt-spray fog test except that equipment located outdoors shall withstand 500 hours. Perform
salt-spray fog test in accordance with ASTM B 117. Each specimen shall have a standard scribe mark as defined
in ASTM D 1654. Upon completion of exposure, evaluate and rate the coating or paint system in accordance with
procedures A and B of ASTM D 1654. The rating of failure at the scribe mark shall be not less than six (average
creepage not greater than 3 mm 1/8 inch). The rating of the unscribed area shall be less than ten (no failure).
Thickness of coating or paint system on the actual equipment shall be identical to that on the test specimens
with respect to materials, conditions of application, and dry-film thickness.
2.6 HEAT RECOVERY SYSTEMS
Heat recovery systems shall be utilized in ventilation units (100 percent outside air units) where the temperature
differentials between supply air and exhaust air is significant. Heat recovery systems shall operate at a minimum
of 70 percent efficiency. The heat recovery systems shall have factory-installed microprocessor controller that
in turn can be connected to a Direct Digital Control (DDC) Building Automation System to monitor temperatures,
[wheel operation,] filter cleanliness, defrost control, and other critical conditions. Prefilters shall be provided
in all heat recovery systems before the heat recovery equipment.
2.6.1 Unit Casing
NOTE: Include bracketed sentences unless condensate drain is not needed or
cross contamination is prevented by other methods.
Provide a self supporting unit casing constructed of minimum 1.1 mm0.04 inches thick extruded aluminum profiles
and aluminum zinc sheet steel that create a double wall. [The base of the casing shall be constructed as a continuous
condensate drain with a total of four connection possibilities.] The casing bottom, top, and sides shall be
insulated with 50 mm2 inch thick fibrous glass insulation with a minimum density of 96 kg per cubic meter6 lb
per cubic foot or another material with equivalent insulating value. [Provide a partition to isolate the exhaust
and supply airstreams from each other to avoid cross contamination.] Partition shall be a minimum of [1.9][_____]
mm[0.075][_____] inches [galvanized steel] [aluminum]. Provide stainless steel casing for corrosive air streams.
The casing shall be designed for diagonal mounting of the heat exchanger access from the side for maintenance
and cleaning. The casing shall be designed with an integral defrost control damper on the heat exchanger section
for defrost control. Provide full size access doors for checking the heat exchanger section.
2.6.2 Heat Exchanger Section
[2.6.2.1 Enthalpy Wheel
A desiccant-impregnated enthalpy wheel with variable speed rotary wheel shall be used in the supply and exhaust
systems. Wheels shall contain media made of a lightweight polymer that is coated with a corrosion-resistant
finish. Etched or oxidized surfaces are not acceptable. Heat transfer surfaces shall be coated with a non-migrating
(permanently bonded) absorbent. [Desiccant shall be silica gel for maximum latent energy transfer.] Wheel shall
allow laminar flow but not radial, and prevent leakage, bypassing, and cross contamination by cross flow within
wheel. The wheel shall have rotor seals specifically designed to limit cross-contamination, and a rotation detector.
Should rotation stop, the rotation detector shall alarm the HVAC control system. Wheel shall not condense water
directly or require a condensate drain for summer or winter operation. Performance rating shall be in accordance
with AHRI 1060.
][2.6.2.2 Heat Pipe
For sensible heat recovery a run-around type heat pipe shall use refrigerant to absorb heat from the air stream
at the air intake and reject the heat back into the air stream at the discharge of the air-handling unit. The
heat transfer between air streams shall take place in a counterflow arrangement. The unit shall have no moving
parts and shall be one piece construction. Tube core shall be [18][25][_____] mm[5/8][1][_____] inch OD seamless
aluminum tubing permanently expanded into the fins to form a firm, rigid and complete metal pressure contact
between the tube and fin collar of all operating conditions. Provide copper tubes and copper fins for corrosive
air streams. Secondary surfaces shall be of continuous plate type aluminum fins, [0.18][_____] mm[0.007][_____]
inch thick, and of corrugated design to produce maximum heat transfer efficiencies. System shall have solenoid
valve control to operate under partial load conditions.
][2.6.2.3 Run-around Coil
The run-around coils shall be used at the exhaust discharge from the building and at the fresh air intake into
the building. [A glycol run-around coil shall be used with control valves and a pump for part load conditions.]
][2.6.2.4 Sensible Heat Recovery Unit
[A cross-flow, air-to-air (z-duct) heat exchanger shall recover the heat in the exhaust and supply air streams.
Z-ducts shall be constructed entirely of sheet metal.] [Heat wheels shall be used for sensible heat recovery.
Unit shall have variable speed drive for controlling the temperature leaving the unit. Wheels shall contain
media made of a lightweight polymer that is coated with a corrosion-resistant finish. Etched or oxidized surfaces
are not acceptable. Wheel shall allow laminar flow but not radial, and prevent leakage, bypassing, and cross
contamination by cross flow within wheel. The wheel shall have rotor seals specifically designed to limit cross-contamination,
and a rotation detector. Should rotation stop, the rotation detector shall alarm the HVAC control system. Wheel
shall not condense water directly or require a condensate drain for summer or winter operation. Performance
rating shall be in accordance with AHRI 1060.]
]2.6.3 Defrost Control Damper Section
Provide an integral defrost control damper section with electric damper motor for defrost control of the heat
exchanger section. The defrost control dampers shall be mounted upstream of the heat exchanger section and shall
be capable of preventing frost build-up on the plates of the heat exchanger. Drain pan shall be stainless steel.
The damper motor shall be located outside of both airstreams.
2.6.4 Angle Filter Box
Provide a side access, galvanized steel duct mounted filter box assembly with integral holding frames suitable
for accommodating [50 mm2 inch][_____] thick filters with a minimum efficiency reporting value of 13. Provide
filter box constructed of minimum 1.3 mm0.05 inch thick galvanized steel with extruded aluminum tracks and individual
universal holding frames with polyurethane foam gaskets and positive sealing clips designed to accommodate various
standard size filters in various efficiency ranges. Provide access doors with positive sealing, heavy duty quick
opening half-twist latches and sponge neoprene gasking on each side of filter box for removal and replacement
of filters. For each filter box provide one magnehelic gauge or inclined manometer with static pressure taps,
shut-off and vent cocks, and aluminum tubing with range 50 to 1470 Pa0.0073 to 0.21 psi.
2.7 FIRE DAMPERS
NOTE: Use 1 1/2 hour rated damper for up to 2 hour fire walls. Use 3 hour
rated damper only for 3 hour or 4 hour fire walls.
Provide [_____] [single leaf] [guillotine] [recessed] [hinged] [type] [curtain type with interlocking blades]
[with frame and operating mechanism housed out-of-[air] [fume] [vapor] stream,] constructed and rated in accordance
with AMCA 500-D. Furnish dampers for indicated stream flow, to equal or exceed fire resistance rating of [1
1/2 hours] [3 hours]. Fire damper shall be rattle-free and shall cause a minimum [5] [10] percent increase in
stream velocity or system static pressure. [For [_____] system[s], stream exposed materials of construction
shall be [_____].] Provide building penetration collars in accordance with AMCA 500-D [and NFPA 91], [unless
otherwise indicated]. Provide one spare fusible link for testing of each fire damper operation and one spare
fusible link for each [10] fire dampers, but not less than two.
2.8 MISCELLANEOUS MATERIALS
2.8.1 Filler Metal, Welding
AWS filler metal specification and grade compatible with base materials to develop full joint strength.
2.8.2 Flashing Materials
[Mill galvanized, phosphatized, steel sheet with minimum spangle, conforming to ASTM A 653/A 653M, Coating G90,
24 gage minimum thickness. Mill No. 1 or 2D finished, stainless steel, fully annealed, soft temper, conforming
to ASTM A 167, Type 304, 0.38 mm 0.015 inch minimum thickness. Mill finished copper, conforming to ASTM B 152/B 152M
, minimum 1487 gram per square meter 16 ounces per square foot.] [As specified in Section [07 60 00] FLASHING
AND SHEET METAL.]
2.8.3 Flexible Connectors
2.8.3.1 General Service
Airtight, fire-retardant, fume and vapor resistant, chloroprene or chlorosulfonated polyethylene impregnated,
woven fibrous glass fabric, rated for continuous service at 121 degrees C 250 degrees F, conforming to UL 214
, with 678 gram per square meter 20 ounce per square yard weight for service at 498 Pa 2 inches water gage and
under and 1017 gram per sqaure meter 30 ounce per square yardweight for service over 498 Pa 2 inches water gage.
Provide with or without integral 24 gage mill galvanized sheet metal connectors.
2.8.3.2 Acoustic Service
Provide as second layer for nonpressure service to 60 degrees C 140 degrees F, leaded sheet vinyl, a minimum
1.40 mm 0.055 inchesthick, weighing a minimum 20.60 kg per square meter 0.87 pounds per square foot, capable
of 10 dBA attenuation in 10 to 10,000 Hz range, suitable for solvent seam or overlap joining and banding.
2.8.3.3 [Fume] [Dust Collection] Service
[3 mm][1/8 inch] [_____] thick, single-ply, synthetic fabric reinforced chloroprene suitable for 107 degrees
C 225 degrees F.
2.8.3.4 High Temperature Service
a. Bellows type metal expansion joints, temperature range minus 29 degrees C to [427] [538]
degrees C 20 degrees F to [800] [1000] degrees F, plus or minus 25 kPa 100 inches water gage
[with interior liner [and exterior cover]].
b. Fabric reinforced, insulated, elastomeric cover expansion joint for operating temperature
up to [204 degrees C] [400 degrees F][_____] [belt] [or] [flange] type for [10 kPa gage] [40
inches water gage] [_____] positive or negative pressure [, with interior liner or baffle].
2.8.4 Flexible Duct
NOTE: The designer shall indicate on the drawings the types of flexible duct
required.
2.8.4.1 Metallic Type
Single-ply [zinc-coated carbon steel] [mill galvanized carbon steel] [Type 316 stainless steel] [two-ply aluminum],
[self-supporting to 2.50 meters 8 foot spans] with corrugated and interlocked, folded and knurled type seam construction,
bendable without damage through 180 degrees with a throat radius approximately 10 times the duct diameter, airtight,
rated for positive or negative working pressure of 3735 Pa 15 inches water gage at [177 degrees C 350 degrees
F for aluminum] [343 degrees C650 degrees F for galvanized steel and stainless steel] UL 181, Class 1 rated,
conforming to NFPA 91.
2.8.4.2 Wire Reinforced Fabric Type
Elastomer impregnated woven synthetic fabric, bonded to and supported by corrosion protected or corrosion resistant
spring steel helix, rated for positive or negative working pressure of [3735 Pa gage at 121 degrees C] [15 inches
water gage at 250 degrees F] [_____] UL 181, Class 1 labelled. Provide with manufacturer's standard metallic
connection collar and clamping fastener assembly [fitted with] [dampers] [and] [extractors] [as indicated].
2.8.4.3 Ball Joints
Fabricated from cast iron or formed sheet metal with outer sections secured with bolts. Provide each half of
the ball joint with tubular stubs for connecting ducts.
2.8.4.4 Slip Joints
Fabricated from tubular sheet metal sections. Provide outer tube with formed steel flat bar clamps. Where required
or indicated, provide a chain or other means to fix relative longitudinal position of outer and inner joint sections.
2.8.5 Gaskets
2.8.5.1 Elastomer Buna N
Sheet, 3 mm 1/8 inch thick, conforming to ASTM D 2000, Type 2BG410B14.
2.8.5.2 Elastomer Chloroprene
Sheet, 3 mm 1/8 inch thick, conforming to ASTM D 2000, Type 2BE410B14.
2.8.5.3 Rubber
Sheet, 3 mm 1/8 inch thick red or black, natural, reclaimed, synthetic rubber or mixture thereof, conforming
to ASTM D 1330.
2.8.6 Protective Coating Materials
2.8.6.1 Baked Unmodified Phenolic
MIL-DTL-12276, Type II.
2.8.6.2 Epoxy Coating
Conform to MIL-PRF-23236, Type I, Class 1 or MIL-P-24441 system, Formula 150 green primer 0.076 mm 3 mils, Formula
151 haze gray 0.076 mm 3 mils, and Formula 152 white 0.076 mm 3 mils.
2.8.6.3 Inorganic Zinc Coating
SSPC Paint 20, Type I-C (Self-cure type).
2.8.6.4 Galvanizing Repair Paint
Conform to MIL-P-21035.
2.8.7 Sealants
NOTE: VOCs may be emitted from duct sealant during the curing process. However,
most fiberglass duct work is assembled using UL 181 approved duct tape, which
is applied to the exterior of the duct board and is not exposed to the air steam.
These tapes have little or no VOCs. Using low-VOC products contributes to the
following LEED credit: EQ4. Include VOC submittal if pursuing this LEED credit,
and coordinate with Section 01 33 29 LEED(tm) DOCUMENTATION.
2.8.7.1 Elastomeric
Sealant specified in these specifications or referenced standards as elastomeric or without further qualification,
shall be silicone, polyurethane, polysulfide, polyisobutylene, or acrylic terpolymer suitable for the service.
For sealing of nongasketed duct joints during fabrication or assembly, sealant shall be polyurethane, acrylic
terpolymer or polysulfide. Sealants shall conform to the following:
a. Silicone: Conforming to FS TT-S-001543, single component type, not requiring primed substrate,
with manufacturer published estimated life of 30 years and a maximum 5 percent shrinkage when
cured.
b. Polyurethane: Conforming to ASTM C 920, Type 2, Class A, single component type, not requiring
primed substrate, with manufacturer published estimated life of 20 years and a maximum 10 percent
shrinkage when cured.
c. Polysulfide: Conforming to ASTM C 920, Type 2, Class A, single component type, not requiring
primed substrate, with manufacturer published estimated life of 20 years and a maximum 10 percent
shrinkage when cured.
d. Polyisobutylene/Butyl: Conforming to FS A-A-272, Type 1, single component type, not requiring
primed substrate, with manufacturer published estimated life of 10 years and a maximum 15 percent
shrinkage when cured.
e. Acrylic Terpolymer: Conforming to ASTM C 920, single component type, not requiring primed
substrate, with manufacturer's published estimated life of 20 years and a maximum 10 percent
shrinkage when cured.
[f. Total volatile organic compounds (VOCs) shall not exceed the limits of SCAQMD Rule 1168
nor the limits of Bay Area AQMD Rule 8-51.]
2.8.7.2 Heat Shrinking over Round Exterior Duct
High molecular weight, irradiated polyethylene band with interior heat activated epoxy adhesive coating for heat
shrinking and epoxy extrusion over round, exterior, duct joints.
2.8.7.3 Hard Cast Caulking for Exterior Ducts
Mineral and adhesive impregnated woven fiber tape with adhesive activator for exterior round or rectangular duct
joints.
2.8.7.4 Caulking of Building Surface Penetration
Foamed silicones, two-component, fire-resistant, [gamma radiation resistant], low-exotherm, room temperature
vulcanizing silicone.
2.9 SPECIALTIES
Steel, cast iron, stainless steel, nonferrous metal, or plastic to match duct construction, or as indicated.
2.9.1 Access Ports, Test
With gasketed screw cap and flange, to suit exhaust service[, 25 mm one inch nominal pipe size].
2.9.2 Damper Regulators
Incremental position indicating and locking type, with satin finish chrome plated, flush surface mounting cover
and regulator box where concealment is required in finished spaces. For splitter dampers, provide splitter tip
mounted trunnion brackets with self-locking screw regulator or rods with external swivel joint brackets.
2.9.3 Blast Gates
Provide means for locking in adjusted position with bolt and nut.
2.9.4 Cast Iron Access Door
Cast iron frame, [hinged and] gasketed cast iron door, quick closing clamps for watertight sealing[, size as
indicated][, 152 by 229 mm 6 by 9 inches minimum size].
2.10 SUPPORTS AND HANGERS
NOTE: The designer shall design all supports, including wind bracing for stacks,
and show all important details on the drawings. SMACNA Accepted Industry Practice
for Industrial Duct Construction is illustrative and does not fix sizes of supports
or allowable loads. Refer to SMACNA round and rectangular duct construction
standards for design tables and other information.
2.10.1 General Requirements for Supporting Elements
Provide ducting systems and equipment supporting elements including but not limited to building structure attachments;
supplementary steel; hanger rods, stanchions and fixtures; vertical duct attachments; horizontal duct attachments;
anchors; supports. Design supporting elements for stresses imposed by systems, with a minimum safety factor
of 4.0 based on duct being 50 percent full of particulate conveyed. Supporting elements shall conform to SMACNA 1403
, SMACNA 1922, SMACNA 1520, [SMACNA 1378,] and NFPA 91, as applicable, and modified and supplementary requirements
specified herein. Do not use weld studs and powder actuated anchoring devices to support mechanical systems
components without prior approval.
2.10.2 Vertical Attachments
Provide in accordance with SMACNA Standards, except mill galvanized iron straps shall be a minimum of 25 mm one
inch wide, 16 gage thick.
2.10.3 Horizontal Attachments
Provide as indicated in accordance with SMACNA Standards.
2.10.4 Supplementary Steel
Provide where required to frame structural members between existing members or where structural members are used
in lieu of commercially rated supports. Such supplementary steel shall be fabricated in accordance with the
AISC 360.
2.10.5 Vibration Isolators
NOTE: See Section 15070, "Mechanical Sound, Vibration, and Seismic Control,"
for guidance given in guide specification technical notes. Definite requirements
should be specified in contract specification for bidders' information.
[Provide vibration isolators with in-series, contained, steel springs, chloroprene elastomer elements, and fasteners
for connecting to building structure attachments. Devices shall be loaded by support system in operating condition
to produce required static spring deflection without exceeding 75 percent of device maximum load rating.] [Conform
to Section [22 05 48.00 20] MECHANICAL SOUND VIBRATION AND SEISMIC CONTROL.]
2.11 DUCTWORK, DUST [AND FUME] COLLECTION
2.11.1 General Requirements for Dust [and Fume] Collection Ductwork
NOTE: Delete all welded seams and flanged joints when not required. However,
factors such as water intrusion under negative pressure in weather exposure
should be considered when construction which is not leak-tight is permitted
for the project. Duct conveying fumes subject to condensation should be leak-tight.
NOTE: Designer must verify that products meeting the indicated minimum recycled
content are available, preferably from at least three sources, to ensure adequate
competition. If not, write in suitable recycled content values that reflect
availability and competition.
[Where specified or indicated] [_____] fabricate system ductwork from black carbon steel [, with welded seams
and flanged and gasketed joints], minimum [5][10][_____] percent post-consumer recycled content, or minimum [20][40][_____]
percent post-industrial recycled content. Construct duct to handle [_____] [wood dust] particulate with an influent
loading of [15,000 grains per [standard liter per second (L/s)] [actual L/s]] [7,000 grains per [standard cubic
feet per minute (scfm)] [actual cubic feet per minute (acfm)] [_____]]. Provide ductwork in accordance with
best practice recommendations and requirements of SMACNA 1922 and SMACNA 1520, for [Class I] [Class II] [Class
III] [Class IV] duct and requirements specified or indicated.
2.11.2 Fabrication of Dust [and Fume] Collection Ductwork
NOTE: Delete all welded seams and flanged joints when not required. However,
factors such as water intrusion under negative pressure in weather exposure
should be considered when construction which is not leak-tight is permitted
for the project. Duct conveying fumes subject to condensation should be leak-tight.
Provide indicated sizes, lengths and configuration without deviation unless otherwise approved. Assemble ductwork
airtight [as defined under paragraph entitled "Ductwork Structural Integrity and Leakage Testing," in this section]
and include necessary reinforcements, bracing, supports, framing, gasketing and fastening to guarantee rigid
construction and freedom from vibration, airflow induced motion, and excessive deflection. For [_____] system,
provide SMACNA Class 1 construction with any of the reference standard seams and connections being acceptable
[, except [_____]]. For [_____] system, provide SMACNA Class [2] [3] [4] construction with welded duct and fitting
seams and welded companion angle or Van-Stone flanges. Welding shall conform to requirements specified herein.
Provide flanges at [branches] [hoods,] [equipment] [and] [enclosure connections,] where necessary for ease of
access to equipment or maintenance disassembly, and where indicated. Provide elbows and fittings a minimum 2
gages heavier than straight ducts of equal diameter.
2.11.3 Radius Elbows
Fabricated from butt welded specified piece gore sections or from formed welded or seamless tubing to a minimum
centerline radius of [2.0] [2.5] [_____] diameters. Assemble, weld, and finish ground gore sections to eliminate
internal projections. Construct gored elbow in accordance with the following:
400 mm diameter and less Over 400 mm diameter
16 inches diameter and less Over 16 inches diameter
90 degree - 5 piece minimum 90 degree - 7 piece minimum
60 degree - 4 piece minimum 60 degree - 6 piece minimum
45 degree - 3 piece minimum 45 degree - 5 piece minimum
30 degree - 3 piece minimum 30 degree - 4 piece minimum
15 degree - 2 piece minimum 15 degree - 3 piece minimum
2.11.4 Flanged Joints
Gasketed with full face gaskets 3 mm 1/8 inch thick red or black rubber as specified under paragraph, "Miscellaneous
Materials," in this section.
2.11.5 Access Doors
Provide hinged, gasketed, and fitted with snap-action closures access doors. Equip access door with gaskets
of common weather stripping type, foamed, closed-cell, elastomer with pressure sensitive adhesive back. Provide
cleanout adjacent to every bend and vertical riser. In horizontal duct runs, locate cleanout door with maximum
of spacing of 4 meters 12 feet for ducts 300 mm 12 inches or less in diameter and 6 meters 20 feet for larger
ducts.
2.11.6 Flexible Connectors
[Provide drawband secured flexible connectors, conforming to requirements specified under paragraph, "Miscellaneous
Materials," in this section, utilizing 3 mm 1/8 inch thick reinforced elastomer, fabricated into a cylindrical
shape by vulcanizing or otherwise bonding longitudinal seam.] [Provide flange secured flexible connectors, conforming
to requirements specified under paragraph entitled "Miscellaneous Materials," in this section, utilizing bellows
type metal expansion joint. Where service temperature exceeds 149 degrees C 300 degrees F, insert 25 mm one
inch thickness of mineral wool.]
2.12 PROTECTIVELY COATED STEEL DUCTS
Ductwork, Protectively Coated Steel, For Corrosive Fume and Vapor Exhaust:
2.12.1 General Requirements for Protectively Coated Steel Ductwork
NOTE: Designer must verify that products meeting the indicated minimum recycled
content are available, preferably from at least three sources, to ensure adequate
competition. If not, write in suitable recycled content values that reflect
availability and competition.
Fabricate [_____] system ductwork from black carbon steel with welded seams, flanged and gasketed joints and
protectively coated interior surfaces including flange faces, using a minimum of [5][10][_____] percent post-consumer
recycled content, or a minimum of [20][40][_____] percent post-industrial recycled content. Construct ductwork
to handle [_____] [fumes] [condensing] [noncondensing] [vapors] containing [_____]. Spiral welded duct is prohibited.
Provided ductwork in accordance with best practice recommendations and requirements of SMACNA 1922 and SMACNA 1520
, for Class [IV] [_____] duct.
2.12.2 Protective Coating
Provide [_____] [and] [_____] protective coatings as specified under "Protective Coating Materials" subparagraph
of paragraph entitled "Miscellaneous Materials," in this section. Provide [_____] coating to interior of duct
[and related fan] surfaces. Coat exterior duct [and related fan] surfaces with same protective coating as specified
for exterior surfaces [primed with] [inorganic zinc coating] [_____]. [Exterior fan surfaces shall be finished
[protectively coated] [primed] [as specified under paragraph, "_____".]] [Field finish exterior surfaces which
have only been primed, as specified in Section 09 90 00 PAINTS AND COATINGS.]
2.12.3 Fabrication of Protectively Coated Ductwork
Construct protectively coated ductwork for corrosive fume and vapor exhaust in accordance with SMACNA 1922 and
SMACNA 1520 and as specified herein. Provide indicated sizes, lengths and configuration without deviation, unless
otherwise approved. Spiral welded duct is prohibited. Install ductwork to be water washable, watertight, self-draining,
and airtight [as defined under paragraph entitled "Ductwork Structural Integrity and Leakage Testing," in this
section]. Provide necessary reinforcements, bracing supports, framing, gasketing, and drainage provisions, and
fastening to guarantee rigid construction and freedom from vibration, airflow induced motion, and excessive deflection.
Rigid construction is required to prevent damage to or failure of protective coating during construction, transport,
erection, and on-off system operation. Only companion angle flanged joints shall be permitted. Weld ducting
and fittings seams. Avoid seams in bottom 80 mm 3 inchesof ducting and in corners wherever practical by bending
of corners and arranging seams high in the side sheets or top sheet. Cracks, laps, sharp inside corners, sharp
sheared edges, weld "icicles," flux, pits, weld spatter, burrs, and similar defects which contribute to coating
discontinuities shall be eliminated by the following: a) welding continuously, b) grinding of metal flush
with surface or to 0.8 mm 1/32 inch radius or to maximum radius permitted by thinner metals, c) Utilizing other
fabrication techniques and subsequent surface preparation abrasive blasting. Removed from the job site for repair
rejected ducting not conforming to these requirements and which exhibit coating thickness deficiency. Welding
shall conform to requirements specified herein. Continuously weld companion flange angles to the inside of the
duct and intermittently weld with 25 mm one inch welds every 100 mm 4 inches on outside of duct. Intermittently
weld girth and transverse reinforcements to duct surface for 25 mm one inch on 152 mm 6 inch centers or spot
welded on 100 mm 4 inch centers. Weld and grind flange and reinforcement angles at corners or ends to form continuous
frames. Provide flanges at [branches,] [hoods,] [equipment] [and] [enclosure connections,] where necessary for
ease of access to equipment or maintenance disassembly, and where indicated. Limit duct lengths in accordance
with size, to permit complete and ready access for welding, grinding, blasting, coating, coating continuity checking
and testing, and visual inspection during fabrication and immediately prior to erection.
2.12.4 Radius Elbows
Fabricated radius elbows from butt welded specified piece gore sections or from formed welded or seamless tubing
to a minimum centerline radius of [2.0] [_____] diameters and preferably 2.5 times the duct diameter. Assemble,
weld, and finish ground gore sections to prevent internal crevices and projections. Construct gored elbow in
accordance with the following:
400 mm diameter and less Over 400 mm diameter
16 inches diameter and less Over 16 inches diameter
90 degree - 5 piece minimum 90 degree - 6 piece minimum
60 degree - 4 piece minimum 60 degree - 5 piece minimum
45 degree - 3 piece minimum 45 degree - 4 piece minimum
30 degree - 3 piece minimum 30 degree - 3 piece minimum
15 degree - 2 piece minimum 15 degree - 2 piece minimum
2.12.5 Flanged Joints
Gasketed with full-face gaskets which are one-piece, heat, adhesive or solvent vulcanized, or bonded and assembled
to prevent drainage and limit extrusion or cavity at joint.
2.12.6 Access and Cleanout Door Openings
Provide access plates upstream and downstream of equipment installed in ductwork, at locations to facilitate
duct cleaning (such as in horizontal runs, near elbow junctions, and vertical runs), and where indicated. For
ducts 300 mm 12 inches diameter or less, locate cleanout or access openings a minimum of 3.70 meters 12 feet
apart. Provide 250 by 300 mm 10 by 12 inches minimum size access opening; unless otherwise indicated or prevented
by duct dimension. Locate opening a minimum of 80 mm 3 inches from bottom of duct. Frame access openings by
welded and ground miter joint 5 mm 3/16 inch thick strap iron, or angle iron, with 6 mm 1/4 inch stainless steel
bolt or stud assembly to duct on 100 mm 4 inch centers. Fabricate plates out of 300 series corrosion-resistant
steel or polyvinyl chloride faced sheet backed by 16 gage sheet metal, reinforced as required for larger sizes,
or constructed of heavier gage metal. Ensure only corrosion resistant materials are expose to duct interior.
Provide one "U" handle on access plates through 250 by 300 mm 10 by 12 inches and two "U" handles on larger sizes.
Locate access openings at points which will permit ready access to duct internals with no duct cutting. Where
access through equipment or access doors specified herein is not available at a specific point, provide 200 mm
8 inch diameter gasketed access plates spaced on maximum 3 meters 10 foot centers. Where penetration of duct
surfaces is approved or specified, provide 300 series corrosion resistant steel fastener assemblies. Provide
hex type, cadmium plated flange fastener bolts and nuts and [3 mm 1/8 inch thick acid resistant chloroprene]
[3 mm 1/8 inch thick Buna N] joint gaskets.
2.13 THERMOPLASTIC DUCTWORK
NOTE: Duct systems of plastic material may be used to handle only nonflammable
corrosive fumes and vapor when conventional metal duct systems will not be adequate.
NOTE: SMACNA Thermoplastic Duct (PVC) Construction Manual is applicable to
fume exhaust systems construction and installation requirements for round and
rectangular PVC ductwork for positive and negative pressure systems operating
in environments up to 27 degrees C at 498 Pa, 1493 Pa, and 2488 Pa 80 degrees
F at 2 inches, 6 inches, and 10 inches water gage. The requirements of this
standard are applicable specifically to Classes 12454-B and 12454-C PVC compounds
as defined in ASTM D 1784, Rigid Poly(Vinyl Chloride) (PVC) Compounds and Chlorinated
Poly(Vinyl Chloride) (CPVC) Compounds. The designer shall indicate on the drawings
the static pressure classification (498 Pa, 1493 Pa, or 2488 Pa 2 inches, 6
inches, or 10 inches water gage positive or negative) to which each duct system
(or each portion of a duct system) is to be constructed.
2.13.1 Ductwork
Construct ductwork, fittings, hoods, and accessories in accordance with SMACNA 1378 and NFPA 91. Fabricate supplementary
steel in accordance with the AISC 360.
2.13.2 Product Requirements
Provide duct system from a manufacturer recognized in the field of fabrication of PVC material. Fabricating
personnel shall be certified by the manufacturer as qualified to perform the work in accordance with the specified
requirements.
2.13.3 Basic Ductwork Materials
NOTE: Designer must verify that products meeting the indicated minimum recycled
content are available, preferably from at least three sources, to ensure adequate
competition. If not, write in suitable recycled content values that reflect
availability and competition.
Fabricate ducts, hoods, accessories and components in sheet form from materials conforming to ASTM D 1927, [Type
I, Grade 1] [Type I, Grade 2]. Content shall be a minimum of [5][10][_____] percent post-consumer recycled content,
or a minimum of [20][40][_____] percent post-industrial recycled content. Utilize extrusions of the same compounds
as specified for duct. Solvent cement shall conform to ASTM D 2564. Construct metal components, when permitted
to be located interior to the duct, of [Type] [304 or 304L] [316 or 316L] [_____] [corrosion resistant steel]
[_____].
2.13.4 Fasteners
Where penetration of duct surfaces is approved or specified, provide Type 316 corrosion resistant steel fastener
assemblies encapsulated with polyester on duct interior, unless total disassembly is intended. Provide flange
fastener bolts and nuts of hex type only, cadmium plated, unless exposed to corrosive fumes; in which case provide
Type 316 stainless steel. Equip bolted assemblies with two oversized washers, except where assembled with metallic
reinforcement contact. Plastic bolting is prohibited.
2.13.5 Joint Gaskets
Provide [3 mm1/8 inch thick acid resistant chloroprene.] [3 mm1/8 inch thick Buna N.]
2.13.6 Fabrication
Construct water washable, watertight, self-draining, and airtight ductwork as specified or indicated. Provide
required reinforcements, bracing, supports, framing, gasketing, sealing, resilient mounting, drainage provisions,
and fastening to guarantee rigid construction and freedom from vibration, airflow induced motion and noise, and
excessive deflection at specified maximum system pressure and velocity.
2.13.6.1 Flanges
Provide flanges at all branches on maximum 6 meters 20 foot centers in ducting sized 400 mm 16 inches and under,
on maximum 2.40 meters 8 foot centers in duct sized over 400 mm 16 inches, where required for ease of access
to equipment, at hoods, enclosure connections and where indicated. Furnish one piece, heat, adhesive, or solvent
vulcanized or bonded full face gaskets at flange joints.
2.13.6.2 Access Plates
Provide access plates upstream and downstream of equipment in ducts at locations to facilitate duct cleaning,
and where indicated. Locate access openings a minimum of 50 mm 2 inches above bottom of duct and externally
frame with welded and ground miter joint steel which is isolated from duct interior. Construct access plate
with PVC on interior side, backed with steel on exterior side. Provide stainless steel access plate fasteners.
For ductwork cleaning access, provide 200 mm 8 inchdiameter gasketed access plates on maximum 3 meters 10 foot
on centers, except where access is available through an air terminal device or other required access.
2.14 FIBERGLASS DUCTWORK
NOTE: Duct systems of plastic material may be used to handle only nonflammable
corrosive fumes and vapor when conventional metal duct systems will not be adequate.
Ductwork, Fiberglass for Nonflammable [Corrosive] [Fume] [Vapor] Exhaust:
2.14.1 Fiberglass Ductwork
Construct ductwork, fittings, accessories, and material of construction in accordance with NFPA 91, and ASTM C 582
. Fabricate supplementary steel in accordance with the AISC 360.
2.14.2 Basic Ductwork Materials
NOTE: Fill in resin characteristics from ASTM C 582 if necessary. Verify suitability
of Type 316 stainless steel for the specific chemical exposure; for example,
chromic acid attacks Type 316 stainless steel. Revise as required.
NOTE: Designer must verify that products meeting the indicated minimum recycled
content are available, preferably from at least three sources, to ensure adequate
competition. If not, write in suitable recycled content values that reflect
availability and competition.
Fabricate ducts, accessories and components in sheet form from materials conforming to ASTM C 582 [, RTP _____].
Content shall be a minimum of [5][10][_____] percent post-consumer recycled content, or a minimum of [20][40][_____]
percent post-industrial recycled content. Provide exterior gel coat, coating or paint with ultraviolet light
inhibiting properties for ducts exposed to sunlight. Construct metal components, when permitted to be located
interior to the duct, of Type 316 corrosion resistant steel.
2.14.3 Fasteners
Where penetration of duct surfaces is approved or specified, provide Type 316 corrosion resistant steel fastener
assemblies encapsulated with polyester on duct interior, unless total disassembly is intended. Provide flange
fastener bolts and nuts of hex type only, cadmium plated, unless exposed to corrosive fumes; in which case provide
Type 316 stainless steel. Equip bolted assemblies with two oversized washers, except where assembled with metallic
reinforcement contact. Plastic bolting is prohibited.
2.14.4 Joint Gaskets
Provide [3 mm1/8 inch thick acid resistant chloroprene.] [3 mm1/8 inch thick Buna N.]
2.14.5 Fabrication
Construct water washable, watertight, self-draining, and airtight ductwork as specified or indicated. Provide
required reinforcements, bracing, supports, framing, gasketing, sealing, resilient mounting, drainage provisions,
and fastening to guarantee rigid construction and freedom from vibration, airflow induced motion and noise, and
excessive deflection at specified maximum system pressure and velocity.
2.14.5.1 Flanges
Provide flanges at all branches on maximum 6 meters 20 foot centers in ducting sized 400 mm 16 inches and under,
on maximum 2.40 meters 8 foot centers in duct sized over 400 mm 16 inches, where required for ease of access
to equipment, at hoods, enclosure connections and where indicated. Furnish one piece, heat, adhesive, or solvent
vulcanized or bonded full face gaskets at flange joints. Provide flanges at dissimilar material joints, such
as between fiberglass reinforced plastic (FRP) and PVC.
2.14.5.2 Access Plates
Provide access plates upstream and downstream of equipment in ducts at locations to facilitate duct cleaning,
and where indicated. Locate access openings at least 50 mm 2 inches above bottom of duct and externally frame
with welded and ground miter joint steel which is isolated from duct interior. Contruct access plate with fiberglass
on interior side, backed with steel on exterior side. Provide Type 316 stainless steel access plate fasteners.
For ductwork cleaning access, provide 200 mm 8 inch diameter gasketed access plates on not more than 3 meters
10 foot centers, except where access is available through an air terminal device or other required access provision.
2.15 VEHICLE TAIL PIPE EXHAUST SYSTEM
NOTE: Specifications included are for maintenance work. Dynamometer applications
require revised specifications with special considerations for high temperatures
involved. Following are kW/cms horsepower/cfm of exhaust gas recommendations
for sizing system and hoses for maintenance work applications.
Maintenance-gasoline: 223 (kW/0.07 m3/s; 261/0.09; 373/0.19 299 (HP)/150 (CFM);
350/200; 500/400
Maintenance-diesel: 224/0.19; 373/0.28; 522/0.47 300/400; 500/600; 700/1000
Turbo-charged diesel: to 373/0.66 500/1400
2.15.1 General Requirements for Vehicle Tail Pipe Exhaust System
Provide a hanging [exposed overhead] [disappearing overhead] [disappearing underfloor] [nondisappearing (plug-in
underfloor)] type vehicle tail pipe exhaust system. Construct and install in accordance with applicable requirements
of NFPA 91.
2.15.2 Ductwork
Construct ducts and miter or stamped fittings with galvanized steel. Duct sheet metal gages shall conform to
Class I in SMACNA 1922 and SMACNA 1520.
2.15.2.1 Suction Side Ductwork
Construct suction side ductwork with lock groove seam longitudinal joints. Connect circumferential joints between
sections with push-on or bead and crimp type, secured with a minimum 4 rivets or screws on ducts up to and including
100 mm 4 inches diameter, and with screws or rivets a minimum 80 mm 3 inches on center on larger sizes of duct.
Lap joints in the direction of air flow. On disappearing overhead systems, assemble roller duct sections using
pop rivets. Solder all joints or construct ductwork leak-tight as for discharge side ductwork below.
2.15.2.2 Discharge Side Ductwork
Construct ductwork on the discharge side of the fan leak-tight with joints and seams welded, brazed, or soldered.
Provide flanges with suitable gaskets, where required. Repair damaged galvanizing with galvanizing repair compound.
2.15.3 Fan
NOTE: The criteria for special AMCA construction for protective coating can
be further delineated here or incorporated into referenced paragraph, if this
is the only fan. Specify welded Class II construction only where required.
NOTE: See Section 15070, "Mechanical Sound, Vibration, and Seismic Control,"
for guidance given in guide specification technical notes. Definite requirements
should be specified in contract specification for bidders' information.
Comply with paragraph entitled "Centrifugal Fans," in this section [, subparagraph "Utility Set,"] and special
requirements for protective coatings. [Provide unit of all welded construction, utilizing minimum 14-gage carbon
steel in AMCA Class II construction.] [Internal and external protective coating shall be manufacturer's standard,
engineered quality type, with properties comparable to [air-dry or baked phenolic,] [or] [epoxy] applied in multiple
coats of 0.10 to 0.15 mm 4 to 6 mil dry film thickness.] [Mount entire assembly for vibration isolation on structural
steel base and spring or elastomer type isolators with minimum transmissibility of [10] [5] percent.] [Provide
split sleeve or flexible connection at fan inlet.]
2.15.4 Flexible Tail Pipe Exhaust Tubing and Connectors
Provide interlocking helical seam metallic type construction of 0.3 mm 0.012 inch minimum thickness up to and
including 150 mm 6 inch diameter and 0.51 mm 0.020 inch minimum thickness over 150 mm 6 inches diameter Type
302, 304, or 321 corrosion-resistant steel [with inside diameter] [and length as shown.] [of] [80] [100] [125]
[150] [200]mm and [_____] meters in length [3] [4] [5] [6] [8] [inches] and [_____] feet in length. Connect
to duct by welding or with screws or flanged joint with gasket [and fit with tail pipe adapters constructed of
minimum 20 gage Type 300 or 400 Series stainless steel, and which include provisions for secure tail pipe attachment].
Secure hose terminal connections by screws, clamps, or flanged connections. [Provide winch operated hose assembly.]
2.15.5 Supporting Elements
Support ducting [as indicated] with anti-sway bracing to resist perceptible movement in response to forces imposed
by flexible tubing location on handling. Suspend tubing from overhead location and provide means to raise and
lower for use. Assemble suspension system with rigid pulley restraint, 3 mm 1/8 inch diameter aircraft cable,
pulleys, and manually operated winch fitted with safety ratchet lock and slip resistant hand grip.
2.16 WELDING FUME EXHAUST SYSTEM
2.16.1 General Requirements for Welding Fume Exhaust System
Provide a [hanging] [long reach type] welding fume exhaust system as specified and indicated. Construct and
install in accordance with applicable requirements of NFPA 91.
2.16.2 Ductwork
Construct ducts and stamped fittings with galvanized steel. Duct sheet metal gages shall conform to Class I
in SMACNA 1922 and SMACNA 1520.
2.16.2.1 Suction Side Ductwork
Construct suction side ductwork with lock groove seam longitudinal joints. Connect circumferential joints between
sections with push-on or crimp and bead type, secured with a minimum 4 rivets or screws up to and including 100
mm 4 inches diameter, and with screws or rivets a maximum 80 mm 3 inches on center on larger sizes of duct.
Lap joints in the direction of air flow.
2.16.2.2 Discharge Side Ductwork
Construct ductwork on the discharge side of the fan leak-tight with joints and seams welded, brazed, or soldered.
Provide flanges with suitable gaskets, where required. Repair damaged galvanizing with galvanizing repair compound.
2.16.3 Fan
NOTE: The criteria for special AMCA construction for protective coating can
be further delineated here or incorporated into referenced paragraph, if this
is the only fan. Specify welded Class II construction only where required.
NOTE: See Section 15070, "Mechanical Sound, Vibration, and Seismic Control,"
for guidance given in guide specification technical notes. Definite requirements
should be specified in contract specification for bidders' information.
Comply with paragraph entitled "CENTRIFUGAL FANS" [, subparagraph "Utility Set,"] in this Section and special
requirements for protective coatings. [Provide unit of all welded construction, utilizing a minimum 14-gage
carbon steel in AMCA Class II construction.] [Internal and external protective coating shall be manufacturer's
standard, engineered quality type, with properties comparable to [air-dry or baked phenolic,] [or] [epoxy] applied
in multiple coats of 0.10 to 0.15 mm 4 to 6 mil dry film thickness.] [Mount entire assembly for vibration isolation
on structural steel base and spring or elastomer type isolators with a minimum transmissibility of [10] [5] percent.]
[Provide split sleeve or flexible connection at fan inlet.]
2.16.4 Flexible Welding Fume Exhaust Tubing and Connectors
Provide corrosion protected, spring steel helix reinforced, neoprene impregnated, woven fibrous glass fabric
laminate, flexible tubing with cuffed ends or equivalent construction, and with an inside diameter [and length
as shown.] of [100] [125] [150] mm [and _____ meters in length] [4] [5] [6] inches [and _____ feet in length]
. Connect to duct with clamp or gasketed flange [and fit with swivel connected conical fume hood, constructed
of minimum 20 gage aluminum [or 26 gage galvanized steel] [or ABS plastic] and fitted with 13 mm 1/2 inch mesh
intake screen and magnets for holding receptor in fixed location]. Secure tubing to terminal devices by clamping.
[Provide spring or weight counterbalanced supporting arms for flexible hose section of long reach system.]
2.16.5 Supporting Elements
Support ducting [as indicated] with anti-sway bracing to resist perceptible movement in response to forces imposed
by flexible tubing location on handling. Suspend tubing from overhead location [and provide means to raise and
lower for use]. [Assemble suspension system with rigid pulley restraint, 3 mm 1/8 inch diameter aircraft cable,
pulleys, and manually operated winch fitted with safety ratchet lock and slip resistant hand grip.] [Support
movable portion of long reach system with brackets.] Observe that hood remain in a fixed position after manual
adjustment.
2.17 STACKHEADS
Provide SMACNA 1403 no loss type stackheads for vertical discharge to the atmosphere unless indicated otherwise.
Weather caps are prohibited. Provide bracing or guy wires for wind loads on stacks as indicated. Discharge
stacks should be vertical and terminate at a point where height or velocity prevents reentry of exhaust air.
PART 3 EXECUTION
3.1 INSTALLATION
3.1.1 Installation Requirements
NOTE: Ductwork for Class 2, 3, and 4 service and supporting elements shall
be able to sustain working live loads imposed by ducting 50 percent filled with
particulate material being conveyed. Provide supplementary structural steel
for the support of system components.
Install in accordance to NFPA 91, and SMACNA 1922, and SMACNA 1520. Provide mounting and supports for equipment,
ductwork, and accessories, including structural supports, hangers, vibration isolators, stands, clamps and brackets,
access doors, blast gates, and dampers. Install accessories in accordance with the manufacturer's instructions.
Construct positive pressure duct inside buildings airtight.
3.1.1.1 Wood Facilities
NOTE: Include paragraphs when appropriate. For other projects, edit as required
and include appropriate references.
For [wood processing] [and] [woodworking] facilities, conform to NFPA 664.
3.1.1.2 Aluminum Facilities
NOTE: Include paragraphs when appropriate. For other projects, edit as required
and include appropriate references.
For aluminum [processing] [and] finishing facilities, conform to NFPA 65.
3.1.2 Electrical Ground Continuity
Where electrical ground continuity is required, provide brazed connection insulated, multi-strand, copper wire
jumpers across points of discontinuity. Provide connection to ground and continuity testing as part of the work
of Division 16.
3.1.3 Special Installation Requirements
Special installation requirements for protectively coated steel ductwork for corrosive fume and vapor exhaust:
Slope horizontal ducts [25] [_____] mm in [12] [_____] meters [one] [_____] inch in [40] [_____] feet in the
direction of air flow or [25] [_____] in [3] [_____] meters [one] [_____] inch in [10] [_____] feet in the direction
opposite to airflow. Where necessary, slope duct to common drainage point. Provide drains at low points, at
internal duct restrictions, at base of risers and where indicated. Provide drain connections of 25 mm one inch
pipe size corrosion resistant steel couplings welded to duct and provided with polytetrafluoroethylene paste
lubricated PVC plug where drainage piping is not indicated. Provide drain lines with a trap of 25 mm one inch
greater depth than the positive or negative pressure in the duct but not less than 50 mm 2 inches. Provide
duct support system to include additional weight due to collection or [condensate] [and] washing water in nondrainable
deflected surface and other areas. Provide duct supports and building structure attachments in accordance with
SMACNA 1922 and SMACNA 1520.
3.1.4 Special Requirements for Installation of Thermoplastic Ductwork
Requirements for installation of thermoplastic ductwork for nonflammable corrosive fume and vapor exhaust:
3.1.4.1 Slope
Slope horizontal ducts [25] [_____] mm in [12] [_____] meters [one] [_____] inch in [40] feet in the direction
of airflow or [25] [_____] in [3] [_____] meters [one] [_____] inch in [10] [_____] feet in opposite to the direction
of airflow. Where necessary, slope duct to common drainage point.
3.1.4.2 Drains
Provide drains at all low points, at internal to duct drainage restrictions, at base of risers, and where indicated.
Provide drain connections of 25 mm one inch IPS couplings with polytetrafluoroethylene paste lubricated plug
where drainage piping is not indicated, and where piping is indicated, provide PVC Type DWV piping conforming
to ASTM D 2665 to points indicated. Provide trap of 25 mm one inch greater depth than the positive or negative
pressure in the duct but not less than 50 mm 2 inches.
3.1.4.3 Duct Supports
Isolate duct support contact surfaces from supporting steel by 6 mm 1/4 inch thick closed-cell foamed cellular
elastomer insulation material of a width greater than support. Provide duct support system to include additional
weight due to collection of condensate and washing water in nondrainable, deflected surface and other areas.
3.1.5 Special Requirements for Installation of Fiberglass Ductwork
Requirements for installation of fiberglass ductwork for nonflammable corrosive fume and vapor exhaust:
3.1.5.1 Slope
Slope horizontal ducts [25] [_____] mm in [12] [_____] meters [one] [_____] inch in [40] [_____] feet in the
direction of airflow or [25] [_____] mm in [3] [_____] meters [one] [_____] inch in [10] [_____] feet in opposite
to the direction of airflow. Where necessary, slope duct to common drainage point.
3.1.5.2 Drains
Provide drains at all low points, at internal drainage restrictions, at base of risers, and where indicated.
Provide drain connections of 25 mm one inch IPS couplings with polytetrafluoroethylene paste lubricated plug
where drainage piping is not indicated, and where piping is indicated, provide PVC Type DWV piping conforming
to ASTM D 2665 to points indicated. Provide a trap of one inch greater depth than the positive or negative pressure
in the duct but not less than 50 mm 2 inches.
3.1.5.3 Duct Supports
Isolate duct support contact surfaces from supporting steel by 6 mm 1/4 inch thick closed-cell foamed cellular
elastomer insulation material of a width greater than support. Design duct supporting system to include additional
weight due to collection of condensate and washing water in nondrainable, deflected surface and other areas.
3.1.6 Miscellaneous Sheet Metal Work
Provide [_____] and [_____], fabricated from [mill galvanized steel] [black steel and protectively coated] [aluminum]
[_____], as indicated. Sheet metal thickness, reinforcement and fabrication, where not indicated, shall conform
to SMACNA 1403.
3.1.7 Building Penetrations
3.1.7.1 General Penetration Requirements
Provide properly sized, fabricated, located, and trade coordinated sleeves and prepared openings, for duct mains,
branches, and other item penetrations, during the construction of the surface to be penetrated. Provide sleeves
for round duct 380 mm 15 inches and smaller and prepared openings for round duct larger than 380 mm 15 inches
and square or rectangular duct. Fabricate sleeves, except as otherwise specified or indicated, from 20 gage,
1.00 mm 0.0396 inch thick mill galvanized sheet metal. Sleeves penetrating load bearing surfaces shall be standard
weight galvanized steel pipe. Provide roof penetrations as shown in SMACNA 1403.
3.1.7.2 Framed Opening
Provide framed openings in accordance with approved shop drawings. Refer to paragraph entitled "Fire Dampers,"
in this section, for related work.
3.1.7.3 Clearances
Provide a minimum 25 mm one inch clearance between penetrating and penetrated surfaces. Fill clearance space
with bulk fibrous glass or mineral wood [or foamed silicone] and seal and close.
3.1.7.4 Tightness
Penetration shall be [weathertight] [fireproof where fire rated surfaces are penetrated] [vaportight to prevent
vapor transmission to conditioned spaces] [sound tight to prevent sound transmission to or between normally occupied
or finished spaces] [deleterious or hazardous substance-tight where] [toxic] [flammable] [_____] [substances
or gases could migrate].
3.1.7.5 Sealants
Provide sealant of [_____] [elastomeric] type [or foamed silicone type], as specified under paragraph entitled
"Sealants," in this section. Apply to oil free surfaces to a minimum 10 mm 3/8 inch depth.
3.1.7.6 Closure Collars
Provide a minimum 100 mm 4 inches wide, unless otherwise indicated, for exposed ducts and items on each side
of penetrated surface, except where equipment is installed. Install collar tight against the surface and fit
snugly around penetrating item without contact. Grind sharp edges smooth to prevent damage to penetrating surface.
Fabricate collars for round ducts 380 mm 15 inches in diameter or less from 20 gage, 1.00 mm 0.0396 inch nominal
thickness, mill galvanized steel. Attach collars a minimum of 4 fasteners to where the opening is 300 mm 12
inches in diameter or less, and a minimum of 8 fasteners where the opening is 500 mm 20 inches in diameter or
less. Fabricate collars for square and rectangular ducts with a maximum side of 380 mm 15 inches or less from
20 gage, 1.00 mm 0.0396 inch nominal thickness, mill galvanized steel. Fabricate collars for round, square,
and rectangular ducts with minimum dimension over 380 mm 15 inches from 18 gage, 1.40 mm 0.0516 inch in nominal
thickness, mill galvanized steel. Install collars with fasteners a maximum of 150 mm 6 incheson center. [Where
penetrating items are irregularly shaped and where approved, smoothly finished, fire-retardant, foamed silicone
elastomer may be utilized without closure collar.]
3.1.8 Installation of Fire Dampers
Install fire dampers at locations indicated. Provide units and connecting ductwork in accordance with applicable
provisions of [NFPA 91,] [UL Bld Mat Dir,] AMCA 500-D [and UL 33], [and as indicated]. Install retaining angles,
sleeves, break-away connections, and duct access doors at each damper, as required. Minimum thickness of sleeves
shall be 14 gage [, except as otherwise indicated]. Duct access doors shall be hinged [and fitted with UL listed
glass viewing port assembly]. Prior to acceptance, simulate conditions to cause each unit to function automatically.
Apply safe, nonflame, heat source to fusible links and replace test activated fusible links.
3.1.9 Installation of Flexible Connectors
Flexibly connect duct connected and vibration isolated fans [, ducts crossing building expansion joints] and
specified or indicated components [, except where direct connections are specified or indicated]. When fans
are started, stopped, or operating, flexible connector surfaces shall be curvilinear, free of stress induced
by misalignment or fan reaction forces, and shall not transmit vibration. Leakage shall not be perceptible to
the hand when placed within 150 mm 6 inches of the flexible connector surface or joint. Provide a minimum of
150 mm 6 inches and a maximum of 610 mm 2 feet active length with a minimum of 25 mm one inch of slack, secured
at each end by folding in to 24 gage sheet metal or by metal collar frames.
3.1.10 Installation of Supports
3.1.10.1 Selection
Select duct and equipment support system taking into account the best practice recommendations and requirements
of SMACNA 1922, SMACNA 1520, and NFPA 91; location and precedence of work under other sections; interferences
of various piping and electrical work; facility equipment; building configuration; structural and safety factor
requirements; vibration and imposed loads under normal and abnormal service conditions. Indicated support sizes,
configurations, and spacings are the minimal type of supporting component required for normal loads. Where installed
loads are excessive for the normal support spacings, provide heavier duty components or reduce the element spacing.
After system start-up, replace or correct support elements which vibrate and cause noise or possible fatigue
failure. Exercise special care to prevent cascading failure.
3.1.10.2 General Requirement for Supports
NOTE: See Section 15070, "Mechanical Sound, Vibration, and Seismic Control,"
for guidance given in guide specification technical notes. Definite requirements
should be specified in contract specification for bidders' information.
Securely attach supporting elements to building structural steel or structural slabs. Where supports are required
between building structural members provide supplementary structural steel as specified for work under this section.
On submittals show location of supports and anchors and loads imposed on each point of support or anchor. Do
not hang ductwork or equipment from piping, or other ducts or equipment. Attach supports to structural framing
member and concrete slab. Do not anchor supports to metal decking unless a means is provided and approved for
preventing the anchor from puncturing the metal decking. Where supports are required, between structural framing
members, provide suitable intermediate metal framing. Where C-clamps are used, provide retainer clips. A maximum
span of 3 meters 10 feet shall exist between any two points, with lesser spans as specified or as required by
duct assemblies, interferences, and loads imposed or permitted. Provide a minimum one set of two vertical support
elements for each point of support and each length of duct, except as otherwise specified. Install supports
on both sides of all duct turns, branch fittings, and transitions. Cross-brace hangers sufficiently to eliminate
sway. Perforated strap hangers are prohibited. Where ductwork system contains heavy equipment, hang such equipment
independently of the ductwork. [Duct supports shall be vibration isolated from structure at points indicated.]
[Provide vibration isolators in indicated discharge ducting system for a minimum distance of [15 meters] [50
feet][_____] beyond the fan. Coordinate deflection of duct and equipment mountings and conform to Section [
22 05 48.00 20] MECHANICAL SOUND VIBRATION AND SEISMIC CONTROL.] [The location of supporting elements shall
be limited by the allowable load on the purlin which shall be limited to that no greater than the moment produced
by 4450 Newton one Kip load at mid-span of purlin. When the hanger load exceeds these limits, provide reinforcing
of purlin[s] or additional support beam[s]. When an additional beam is used, the beam shall bear on the top
chord of the roof trusses and bearing shall be over gusset plates of top chord. Stabilize beam by connection
to roof purlin along bottom flange.]
3.1.10.3 Methods of Attachment
Clamp, or weld when approved, attachment to building structural steel in accordance with AWS D1.1/D1.1M. Construct
masonry anchors selected for overhead applications of ferrous materials only. Install masonry anchors in rotary,
non-percussion, electric drilled holes. Self-drilling anchors may be used provided masonry drilling is performed
with electric hammers selected and applied in such a manner as to prevent concrete spalling or cracking. Pneumatic
tools are prohibited.
3.1.11 Welding
Welding test agenda shall be done in accordance with the applicable provisions of AWS D1.1/D1.1M and AWS D1.3/D1.3M
.
3.1.12 Test Ports
NOTE: The designer shall indicate on the drawings the location of test ports
required for proper testing, including static pressure, velocity pressure, and
test openings for sampling discharge stack or duct. See ACGIH 2092 for recommendations
in the chapter on testing.
Provide test access ports at points required for work under paragraph entitled "Testing, Adjusting, and Balancing,"
in this section. Locate test ports in straight duct as far as practical downstream of fans, change of direction
fittings, takeoffs, interior to duct accessories, and like turbulent flow areas.
3.1.13 Ductwork Cleaning
Protect duct openings from construction debris using temporary caps, flanges, or other approved means. Clean
ductwork in accordance with manufacturer's recommendations [and the North American Insulation Manufacturers Association
(NAIMA) Guide on Cleaning of Duct Board Materials]. [Clean dirty duct interior with high velocity water and
oil-free air streams or by vacuum cleaning as required by project conditions. ][Test watertight duct work for
proper support, leakage, and unacceptable drainage provisions by intermittently spraying interior with garden
hose nozzle, at a rate of 0.2 liter per second 3 gallons per minute, exercising care to prevent excessive water
accumulation.] After construction is complete but accessible and prior to acceptance, remove all construction
debris from exterior surfaces. Do not close duct inspection ports until inspected by the Contracting Officer.
3.1.14 Protective Coating Work
3.1.14.1 General Requirements for Protective Coating Work
Provide protective coating on interior [and exterior] surfaces of [_____] [and] [interior] [and] [exterior] surfaces
of [_____] with [_____] system as specified hereafter. Prime coat exterior surfaces of [_____] [and] [_____]
with [_____] [inorganic zinc coating as part of work under this section] [.] [, for field finishing of exterior
surfaces as part of work under Section [09 90 00] PAINTS AND COATINGS.] Brush primer, or protective coating
where no primer is specified, onto corners and into crevices and welds, working the material into irregular surfaces
for a holiday free finish.
3.1.14.2 Baked, Unmodified Phenolic System
a. General: The following shall govern for a protective coating system based on unmodified
phenol-formaldehyde resin intended for shop application to [black carbon steel] [_____] surfaces
in [fume] [vapor] exhaust service with possibility of materials concentration by condensation
and subsequent evaporation. Shop apply coating by an applicator approved or licensed by the
coating manufacturer.
b. Surface Preparation: Clean and blast surfaces with dry abrasive to "White Metal" and critical
profile and anchor pattern in accordance with SSPC SP 5, and requirements and recommendations
of the coating manufacturer.
c. Application: The complete system shall include the application of two coats of red pigmented
base followed by not less than one coat of the clear finish, to provide a total minimum dry
film thickness of [0.15 mm] [6 mils] [_____]. Apply coating materials by conventional industrial
pressure spray equipment. Use only those thinners and cleaners in amounts recommended by the
manufacturer. Heat-cure each coat between coats and bake surfaces after the last coat in accordance
with manufacturer's applicable published instructions and specific instructions for the specified
application. Baking time between coats shall be a minimum 1 1/2 to 2 hours at 93 to 121 degrees
C 200 to 250 degrees F. Baking after top coat shall be one hour at 93 to 177 degrees C 200
to 350 degrees F, plus 2 hours final bake at a temperature of [177] [204] degrees C [350] [400]
degrees F. Other baking schedules to achieve required quality coating may be proposed.
d. Repair: Return damaged surfaces to the applicator's shop for repair, unless otherwise approved
by the Contracting Officer.
3.1.14.3 Inorganic Zinc Coating System
a. General Requirements, Inorganic Zinc Coating System: The following shall govern for a protective
coating system primer based on inorganic zinc coating intended for shop application to [_____]
[specified] black carbon steel surfaces with subsequent field finishing with compatible tie
coat and [epoxy] [acrylic latex] [modified acrylic] [chlorinated rubber] top coat [applied as
part of work under Section 09 90 00 PAINTS AND COATINGS.]
b. Surface Preparation: SSPC SP 5.
c. Application: Apply one coat at [0.05 to 0.10] [0.10 to 0.13] mm [2 to 3] [3 to 5] mils
dry film thickness by airless or conventional spray equipment. Use only those thinners and
cleaners in amounts recommended by the manufacturer.
d. Repair: Field repair damaged surfaces in accordance with manufacturer's instructions.
3.1.14.4 Field Inspection of Protective Coating Work
Visually inspect coated surfaces from a maximum distance of 1.5 meters 5 feet with special attention given to
corners and crevices. Check coating thickness in accordance with SSPC Paint 11. Perform inspection immediately
prior to erection of ductwork and equipment and in the presence of the Contracting Officer. Repair coating as
required. Apply additional coating if thickness is not sufficient.
3.1.15 Factory and Field Painting and Finishing
3.1.15.1 Factory Work
Factory finish interior ferrous metal and other specified metallic equipment and component surfaces with manufacturer's
standard surface preparation, primer, and finish coating. Factory finish exterior to building space ferrous
metal surfaces and other exterior to building and interior to building metallic or nonmetallic surfaces with
specified protective coating system in accordance with the paragraph entitled "Protective Coating Material,"
in this section and otherwise with manufacturer's standard surface preparation, primer and finish which meet
the requirements of paragraph entitled "Corrosion Prevention."
3.1.15.2 Field Work
Touch-up or if necessary, repaint factory applied finishes which are marred, damaged, or degraded during shipping,
storage, handling, or installation to match the original finish. Clean and prime field or shop fabricated ferrous
metals required for the installation specified under this section in accordance with the applicable provisions
of Section [09 90 00] PAINTS AND COATINGS. Painting of surfaces not otherwise specified and finish painting
of items only primed at the factory or elsewhere, are specified as part of the work under Section [09 90 00]
PAINTS AND COATINGS.
3.2 TESTING, ADJUSTING, AND BALANCING
3.2.1 Ductwork Structural Integrity and Leakage Testing
NOTE: In addition to significant energy losses, air leakage from HVAC ducts
and air handling units can cause significant IAQ problems due to unexpected
airflow between indoors and outdoors, and between areas within the building.
Air leakage from supply or return duct work contributes to the condensation
of humid air in building cavities and/or on the neighboring surfaces. Air leakage
can be especially problematic for ducts or AHUs that are located outside the
conditioned spaces.
Inspect and test systems pressure rated higher than 498 Pa 2 inches water gage for structural integrity and leakage
as systems or sections during construction but after erection, as work progresses, in system or section lengths
not exceeding 30 meters 100 feet. Test for structural integrity at [_____] percent in excess of system fan positive
or negative total pressure. Test for leakage at [_____] percent in excess of system fan positive or negative
total pressure. [Leakage test procedure and apparatus shall be in accordance with SMACNA 1143. Total leakage,
prorated to length of duct under test, shall not exceed one percent of system capacity.] [Confirm that duct
leakage is less than three percent of coil airflow for new systems and less than six percent for existing systems.]
Do not permit leakage in positive pressure ducts in buildings carrying flammable or toxic materials.
3.2.2 Power Transmission Components Adjustment
Test and adjust V-belts and sheaves for proper alignment and tension preliminary to operation and after 72 hours
of operation at final speed, in the presence of the Contracting Officer. Belts on drive side shall be uniformly
loaded, not bouncing. [Align direct-drive couplings to less than half of manufacturer's allowable range of misalignment.]
3.2.3 Preliminary Tests
Conduct an operational test on the entire exhaust duct systems, components, and equipment for a period of not
less than 6 hours after power transmission components are adjusted. Replace filters, if any, after preliminary
tests and prior to conducting final acceptance tests.
3.2.4 Testing, Adjusting, and Balancing Work
Perform work in accordance with the applicable and recommended procedures of: ACGIH-2092S. Provide apparatus,
certified, calibrated, instrumentation including that to measure sound levels, motor current, and power factor.
Unless approved otherwise, instruments shall be limited to manometers and approved aneroid type gages (such as
a Magnehelic). Velometers may be used for low velocity measurements if approved by the Contracting Officer.
3.2.5 Systems Volume Acceptance Criteria
Systems final volume shall be within the following limits:
Fan: Plus 10 percent, minus zero percent of design volume at design temperature
Hood or Equipment: Plus or minus [5] [10] percent of design volume at design temperature
Note: Tolerances shall be taken on clean or dirty conditions as indicated on the drawings.
3.2.6 Sound Level Tests
Report to the Contracting Officer in writing, sound levels higher than 84 dBA at hoods or at workers' normal
operating positions at equipment in addition to being included in the required test reports.
3.3 SYSTEM[S] OPERATION DEMONSTRATION
After systems and equipment testing, adjusting, and balancing has been completed and accepted, demonstrate the
complete and correct functioning of systems equipment and controls by operation through normal ranges and sequences,
and by simulation of abnormal conditions, [including the manual tripping of fire dampers]. Manually and automatically
cause every device to function as intended. Readjust, as necessary, any settings and after sufficient operating
time, but not less than [6] [_____] hours, verify ability of equipment and controls to establish and maintain
stable and accurate operation and required system performance. Note any abnormal deviations, such as excessive
vibration, noise, and heat, binding damper mechanisms, and incorrect fan rotation. Make any necessary repairs,
replacements or adjustments.
3.4 WASTE MANAGEMENT
NOTE: Diverting waste from the landfill contributes to the following LEED credit:
MR2. Coordinate with Section 01572 CONSTRUCTION AND DEMOLITION WASTE MANAGEMENT.
Separate waste in accordance with the Waste Management Plan, placing copper materials, ferrous materials, and
galvanized sheet metal in designated areas for reuse. Close and seal tightly all partly used adhesives and solvents;
store protected in a well-ventilated, fire-safe area at moderate temperature.
3.5 SCHEDULE
Some metric measurements in this section are based on mathematical conversion of inch-pound measurements, and
not on metric measurements commonly agreed on by the manufacturers or other parties. The inch-pound and metric
measurements shown are as follows:
Products Inch-Pound Metric
a. Motors
Capacity = 7 1/2 hp = 5 1/2 kW
= 15 hp = 11 kW
= 30 hp = 22 3/8 kW
b. Gaskets
Thickness = 1/8 inch = 3 mm