3. Intermediate metal conduit (IMC). 4. Electric metallic tubing (EMT). 5. Flexible metal conduit (FLEX). 6. Polyvinyl chloride conduit (PVC).

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1 SECTION CONDUITS PART 1 - GENERAL 1.01 DESCRIPTION A. General: Provide conduits, complete, as shown, specified or required per Contract Documents. Principal items include: 1. Rigid aluminum conduit. 2. Rigid steel conduit. 3. Intermediate metal conduit (IMC). 4. Electric metallic tubing (EMT). 5. Flexible metal conduit (FLEX). 6. Polyvinyl chloride conduit (PVC). B. Other Applicable Sections: Requirements of Division 1 and Section apply to work of this Section. PART 2 - PRODUCTS 2.01 MINIMUM SIZE A. Conduit and EMT shall be 1/2" minimum except that conduits in earth shall be 3/4" minimum size. All raceways and fittings shall be new and bear UL label RIGID CONDUIT A. Conduit: Rigid conduit including couplings, locknuts, bushings, and nipples shall be galvanized steel or aluminum, thick wall, threaded. No running thread will be accepted; use nipples, unions or other fittings.

2 B. Fittings: Conduit fittings shall be galvanized steel or aluminum, threaded type, compatible with conduit material INTERMEDIATE METAL CONDUIT (IMC) A. Conduit: IMC conduit shall be galvanized with protective coating on inside. B. Fittings: Couplings shall be galvanized steel with threads on one end and swivel fitting on other end. Locknuts, bushings and nipples shall be galvanized steel, threaded type ELECTRICAL METALLIC TUBING (EMT) A. Tubing: Electrical metallic tubing shall be galvanized steel with protective coating on inside. B. Fittings: Fittings for use in EMT runs shall be galvanized steel. Connectors and couplings shall be steel setscrew type FLEXIBLE METAL CONDUIT (FLEX) A. Conduit: Flexible metal conduit shall be galvanized steel. B. Fittings: Connectors shall be galvanized and shall give positive continuity of ground by a squeeze or setscrew method. When flex is cut square, "jake" type connectors properly screwed into the convolutions of the conduit will be approved. Angle connectors shall be accessible at all times. C. Where exposed to moisture or weather, flex and fittings shall be watertight POLYVINYL CHLORIDE CONDUIT (PVC) A. Conduit: Polyvinyl chloride conduit shall be Schedule 40 with round smooth bore for direct burial. Type EB for concrete encasement may be used for utility services. B. Fittings: Couplings, bends, elbows, adapters and other fittings and materials, including jointing cement, shall be the product of, or as approved by, the conduit manufacturer. Fittings shall be of same basic material as conduit.

3 PART 3 - EXECUTION 3.01 LOCATIONS A. Rigid steel or IMC conduit above 3/4" shall be used for installation in concrete or where exposed to physical injury in all sizes. In dry locations, rigid aluminum conduit may be used in lieu of steel. All power and lighting feeders shall be in rigid conduit or IMC. B. Polyvinyl chloride conduit shall be used for installation in earth for exterior branch circuit wiring and communications and may be used for feeders in earth. Provide ground wire in all power and lighting conduit per NEC Table PVC conduit used for power and communications services and for power feeders shall be concrete-encased. C. Electric metallic tubing may be installed for wiring above ground in dry places, where not subject to mechanical damage, in sizes up through 2" diameter. EMT may be used in sizes no larger than 3/4" in concrete. EMT may be used for telephone and signal wiring in sizes larger than 2" diameter. D. Flexible Metallic Conduit: Short wiring connections to motor and equipment shall be installed in flexible metallic conduit. Connections for fixed motors and other fixed equipment installed under this and other Sections affected by vibration or expansion due to heat shall be made with a short, suitable run of flexible metallic conduit. Install separate green ground conductor in all flexible conduits supplying motors or equipment PREPARATION A. Conduit runs shall be clean and dry before pulling in conductors. Provide nylon pull-line in all empty conduits INSULATED BUSHINGS A. All conduits entering panels, junction boxes, outlets and devices shall be provided with insulated bushings or insulated throat connectors. Bushings for conduits 2" and larger shall be O-Z/Gedney Type "B" or equal BUSHINGS A. Where a data, telephone, intercom, control, etc., conduit terminates in space, that is, not attached to a box or other fitting, a bushing shall be provided to the end of the conduit to protect the future wire from abrasion.

4 3.05 CAPPING 3.06 JOINTS A. Conduit shall be capped during construction by means of manufactured conduit seals or caps to prevent entrance of water or debris, and shall remain closed until ready for use. A. Conduit joints in concrete, masonry walls, or where exposed to weather or moisture, shall be made with an approved joint compound PENETRATIONS OF WALLS BELOW GRADE A. Conduit penetrations of walls below grade shall be made using O- Z/Gedney Type WSK through-wall waterproofing fittings or equal SUPPORTS A. General: Fastenings for raceways shall be made by means of not smaller than 3/16" diameter bolts, expansion bolts, or toggle bolts; or by equivalent approved fastenings. Fastenings, where exposed to weather or moisture, shall be galvanized. Nails or wooden or fiber inserts in masonry, shall not be used. Multiple conduit runs shall be racked on galvanized Unistrut. B. Masonry and Concrete: On masonry or concrete walls, columns or flooring, fastenings shall be made by means of lead expansion shields not smaller than 3/8" diameter by 5/8" long for use with No round head machine screws. Machine screws shall be not less than 1-1/4" long for installation on ceiling and not less than 1" long elsewhere. C. Steel Expansion Shield: Shall be Tampins Union Catalog Stock #2M5275 or an equivalent as manufactured by Star or Phillips. Holes for shields shall be carefully and accurately drilled, using sharp drills, to a depth which will afford the maximum practical engagement of threads (depth no less than 1-1/4" into solid concrete) and installation shall develop full strength for screws. D. Exposed or Accessible Locations: In accessible spaces or where exposed, rigid steel conduit smaller than 1", and EMT smaller than 1-1/4" shall be supported by means of approved galvanized clamps and fastenings. Conduit shall be secured so that it cannot be moved without use of tools.

5 E. Exposed Raceways: Exposed wireway runs shall be made horizontal and vertical and parallel to structural members and lines of building. Bends shall be neat and of not less than minimum radii permitted by Code, or fittings shall be used to obtain a neat appearance INSTALLATION OF PVC CONDUIT A. General: Installation of PVC conduit and fittings and preparation of permanent joints shall be performed in a manner, using cement, as recommended by conduit manufacturer. Care shall be practiced in performing cutting, using guides, proper heating and jigs to prevent crimping or deforming during the bending process. All bends should be made to conform with NEC Table , "Bends: How Made." B. Risers Into Equipment: All risers including bends or sweeps from PVC conduit into pull boxes or panelboards shall be coated rigid steel conduit and suitable adapters shall be furnished and installed as required for such transition. Risers outside of partitions and equipment enclosures shall terminate with threaded steel coupling flush with floor EXCAVATION, TRENCHING AND BACKFILLING A. General: All excavations, trenching, backfilling and compacting for raceways shall be performed under the work of this Section and shall conform to the requirements of Division 2. B. Record Drawings: Accurately locate and dimension all underground runs on the record drawings OPENINGS IN WALLS, CEILINGS AND FLOORS A. General: Openings in existing walls, partitions, ceilings and floors shall be made under this Section. Care shall be taken to avoid piping and equipment and unnecessary damage. Holes shall be a practicable minimum in size and number. Patch, repair and paint in workmanlike, approved manner. Penetrations shall be sealed to maintain existing fire rating. B. Sleeving: Provide galvanized steel sleeving extending 2" above slab for conduit floor penetration. C. Approval: Request written approval from the Architect prior to any core drilling.

6 3.12 CONNECTIONS TO VIBRATION-ISOLATED EQUIPMENT A. All wiring (conduit and conductors) shall be arranged to avoid short circuiting of the vibration isolation system. B. Distribution Transformer: 1. When terminating conduit on transformer enclosure, provide a minimum of 36" of flexible conduit with grounding conductor. C. Rotating Equipment: 1. When feeding from floor stub-up locations, locate the stub-up so as to provide not less than 12 diameters of flexible conduit length with green ground wire, both parallel to, and at right angles to, the equipment rotational centerline. 2. When feeding from an overhead drop, where conduit is supported below an occupied floor, provide maximum length of flexible conduit with green ground wire in the drop and support the rigid horizontal conduit on spring hangers, similar to Mason Industries, Type 30N, within 30' of the vibrating equipment. 3. Circuits to mechanical or electrical equipment in roof penthouses shall be overhead, not through floor below or in conduit buried in slab CONNECTIONS TO MECHANICAL DUCTS A. There shall be no connection to, or contact with, supply or return ducts or the insulation thereon, in any way. Violation will require removal. **END OF SECTION**