SECTION 27 0530

Raceways and Fittings for Communications Systems

Part 1 - General

1.1 Description of Work

The work of this section consists of furnishing and installing conduits, raceways and fittings for above grade installations, underground duct installations and inside buildings as shown on the Drawings and as described herein.

1.2 Related Work

See the following specification sections for work related to the work in this section:
1. 27 0500 General Requirements for Communication Systems

1.3 Standards and Codes

Work and material shall be in compliance with and according to the requirements of the latest revision of the following standards and codes:
1. California Electrical Code (CEC):
  1. 230.8 Raceway Seal
  2. 300.5(G) Raceway Seals
2. American National Standards Institute (ANSI):
  1. C80.1 Specification for Zinc Coated Rigid Steel Conduit
  2. C80.3 Specification for Zinc Coated Electrical Metallic Tubing
3. Electronics Industry Alliance (EIA)
4. Federal Specifications (FS):
  1. A-A-55810 Flexible Metal Conduit
5. National Electrical Manufacturers Association (NEMA):
  1. TC 2 Electrical Polyvinyl Chloride (PVC) Tubing and Conduit (EPC 40 and EPC 80)
6. Telecommunications Industry Association / Electronic Industries Alliance (TIA/EIA)
  1. 569-C-2012: Telecommunications Pathways and Spaces
7. Underwriters Laboratories (UL):
  1. 797 Electrical Metallic Tubing - Steel
  2. 360 Liquid-Tight Flexible Steel Electrical Conduit
  3. 514B Fittings for Cable and Conduit
  4. 6 Rigid Metal Conduit
  5. 651 Schedule 40 and 80 Rigid PVC Conduit
  6. 1479 Fire Tests of Through-Penetrations Firestops
  7. 1 Flexible Metal Conduit

1.4 Submittals

As specified in Division 01 and Section 27 0500.
Catalog Data: Provide manufacturer's descriptive literature.
Single Submittal: A single complete submittal is required for all products covered by this Section.

Part 2 - Product

2.1 Conduits, Raceways:

Galvanized Rigid Steel Conduit (GRS) shall be hot-dip galvanized after fabrication, conforming to ANSI C80.1 and UL 6.
Electrical Metallic Tubing (EMT) shall be steel, hot-dip galvanized after fabrication, conforming to ANSI C80.3 and UL 797. Uni-couple EMT is acceptable.
Flexible conduit: Flexible metal conduit (Greenfield) shall be galvanized steel or aluminum interlocked from a continuous metal strip and shall conform to UL 1 and FS A-A-55810.
Liquidtight flexible conduit: Liquidtight flexible metal conduit shall be liquid-tight (Sealtight) of galvanized steel interlocked from a continuous metal strip with an extruded polyvinyl chloride cover and shall conform to UL 360 and FS A-A-55810.
Rigid non-metallic conduit: Rigid non-metallic conduit for concrete encasement shall be Type EB, all others shall be PVC Schedule 40 (PVC-40 or NEMA TC2 Type EPC-40) conduit approved for underground use and for use with 90°C wires, and shall conform to UL 651.
1. Conduit for use for utility feeders shall comply with utility requirements.

2.2 Conduit Supports

Channels:
1. Supports for multiple conduits shall be cold rolled, carbon steel channels unless otherwise noted.
2. All channels used in exterior, damp, wet or corrosive locations shall be hot dipped galvanized unless otherwise noted. Associated hardware shall have manufacturer’s recommended compatible finish.
3. Channels used in dry interior, non-corrosive environments shall be hot dipped galvanized or Dura-Green finished. Associated hardware shall have manufacturer’s recommended compatible finish.
4. Manufacturer: B-Line B series Strut Systems or approved equal.
Supports for individual conduits shall be galvanized malleable iron one-hole type with conduit back spacer.
Supports for individual EMT conduits shall be galvanized pressed steel single hole straps.
Hardware for supports shall be Kadee clamps and connectors as appropriate for the job conditions, or approved equal.
Clamp fasteners shall be by wedge anchors. Shot in anchors shall not be used.
Provide seismic calculations on individual conduit installations 2” and larger and on conduit racks with supports in excess of 12”.

2.3 Fittings

Provide threaded-type couplings and connectors for galvanized rigid steel (GRS) conduits.
Union couplings shall be Erickson type.
Fittings shall be galvanized steel or galvanized cast ferrous metal; access fittings shall have gasketed cast covers.
Set-screw type and compression-type shall not be used.
Threadless couplings shall not be used.
Provide threaded couplings and raintight conduit (“Meyers”) hubs for rigid steel conduit exposed to weather.
Locknuts and bushings shall not to be used in liquidtight applications.
Provide steel set-screw type or compression-type couplings and connectors for electrical metallic tubing (EMT) conduits. Where set-screw fittings are utilized, the screws are to be “dimpled” and not pointed.
Diecast fittings or aluminum fittings shall not be used.
Fittings for Liquidtight Flexible Metal conduit shall have neoprene gaskets.
Fittings for use with rigid non-metallic conduit shall be PVC and have solvent-weld-type conduit connections.

2.4 Bushings

Bushings shall be the insulated type.
Bushings for rigid steel shall be insulated grounding type.

2.5 Conduit Sealants

Fire Retardant Types: Fire stop material shall be reusable, non-toxic, asbestos-free, expanding, putty type material with a 3-hour rating in accordance with UL 1479. Coordinate with requirements in other sections of the documents. Contractor shall obtain approval of the product and its application from the authority having jurisdiction and is responsible to insure that the application is appropriate for the actual installation.
Water Retardant Types: Link seals are to be used on all below building penetrations.

PART 3 - Execution

3.1 Conduit, Raceway and Fitting Installation

Installation shall comply with the CEC.
Provide a nylon pull cord in each empty raceway. Cord shall be 1/4" in all raceways 1" and larger.
The minimum size raceway shall be 1.5 inch unless indicated otherwise noted.
From pull point to pull point, the sum of the angles of all of the bends and offsets shall not exceed 270 degrees regardless of direction. Back to back elbows in any direction without a straight section a minimum of ten times the diameter of the raceway are prohibited without specific approval in writing by the Engineer.
Treat cut steel surfaces or damaged ends with manufacturer’s recommended corrosion-resistant coating. Application shall follow manufacturer's recommendation.
Coordinate minimum conduit bending radius with type and size of cable to be installed. Conduits for voice / data / video installations are to also confirm to EIA / TIA standards. If a conflict is identified, the more stringent requirement shall prevail.
All exposed conduit and hardware shall be painted per spec section 27 0500.
All conduit openings are to have bushings. If omitted, the conductors shall be removed and replaced after the bushings are installed.

3.2 Location

Galvanized rigid steel conduit shall be used for:
1. All above ground exterior work,
2. Exposed interior work up to eight feet above finished floor including mechanical and electric rooms,
3. Conduits embedded in concrete unless otherwise noted,
4. Conduits in corrosive atmospheres.
Electrical Metallic Tubing (EMT) shall be used for:
1. Interior concealed work,
2. Interior exposed conduit above eight feet as acceptable to the local authority having jurisdiction.
Flexible metal conduit (Greenfield) shall be used for:
1. Interior work in short lengths (six foot maximum),
2. Connection of any vibrating equipment, unless otherwise noted or where liquid tight flexible metal conduit is required.
Flexible metal conduit shall be supported within twelve inches of each end where used for expansion purposes.
Liquidtight flexible metal conduit (Sealtight) shall be used wherever flexible conduit is required and moisture may be present including:
1. Vibrating equipment where moisture may be present,
2. When making connections between two building structures.
3. Liquidtight flexible metal conduit is to be supported within twelve inches of each end where used for expansion purposes
Rigid non-metallic conduit (PVC) for all underground exterior work, unless otherwise noted. Associated vertical elbows shall be galvanized rigid steel.

3.3 Routing

Run all concealed conduits above ceilings and inside walls parallel to building lines, unless otherwise noted.
Run all exposed conduits parallel to building lines, unless otherwise noted.
Coordinate conduit locations with equipment, fixtures, and with structural and architectural elements. Conduits attached to walls or columns shall be as unobtrusive as possible and shall avoid windows.

3.4 Conduit Supports

Properly support all conduits as required by the code. Wherever possible, run all conduits concealed except where otherwise shown on the drawings.
Provide "J" hangers on threaded rods or multiple conduits on trapezes consisting of channels supported by minimum 3/8" threaded rod from the structure above. Conduits shall not be supported from ceiling support wires or t-bar grids. Conduits shall not be supported from ductwork, water, fire sprinkler or HVAC lines
Treat damaged channel finishes with manufacturer’s recommended corrosion-resistant coating. Application shall follow manufacturer's recommendation.
Exposed Conduits:
1. Support exposed conduits within three feet of any junction box, coupling, equipment, fixture or device and at intervals not exceeding code requirements.
2. Wherever possible, group conduits together and support on common supports located away from walls. Support exposed conduits fastened to the surface of the concrete structure by one-hole clamps, or with channels. Use conduit spacers with one-hole clamps.
3. Group together exposed conduits in horizontal runs and support on trapeze hangers unless otherwise noted. Arrange such conduits uniformly and neatly. Trapeze hangers shall consist of channels of adequate size, suspended by means of rods or other suitable means from the structure above the ceiling.
4. Support conduit risers in shafts with channels and straps.

3.5 Moisture Seals

Provide in accordnce with CEC paragraphs 230.8 and 300.5(G).

3.6 Flexible Conduit

Flexible metallic conduit shall have a maximum length of six feet unless otherwise noted.
Flexible metallic conduit shall not be considered as a ground conductor.
Flexible metallic conduit shall be installed only in exposed or accessible locations.

3.7 Underground Raceway

Conduits embedded in concrete floors on grade shall be installed between grids of reinforcing steel, or shall be encased below the floors, provided the concrete is thickened as shown on the Drawings. EMT shall not be embedded in concrete.
Slope all underground raceways to provide drainage. Slope conduit from equipment located inside a building to the pull box or manhole located outside the building.
All PVC conduits terminating into pull boxes and vaults shall be provided with bell fittings at ends.
PVC direct buried conduits shall be installed in soil, covered with sand under a warning tape and compacted soil. Minimum depth 18" below grade. All PVC conduit installed below grade shall be provided with galvanized rigid steel elbows and risers. Rigid Steel shall be wrapped with 20 mil tape and extend minimum 12" above finished grade.
Where multiple conduits are run in parallel, install spacers on five-foot centers so as to maintain a three-inch spacing between conduits.
PVC conduits installed under slabs shall be installed in soil, covered with sand under a vapor barrier and crushed rock. Minimum depth 6" below slab. All PVC conduit installed below slab shall be provided with galvanized rigid steel elbows and risers. Rigid steel shall be wrapped with 20 mil tape and extend minimum 12" above finished grade.
Where conduits penetrate structural members, obtain approval for the associated sleeves and windows from the structural consulting engineer and provide as required.

3.8 Storage of PVC Conduits

Store rigid PVC conduit on a flat surface and shielded from the sun. PVC conduits 3" and larger shall be provided with 48" radius bends. If utilized for voice / data / video conductors, radiuses shall conform to TIA / EIA standards.

End Section

Version 20130214.1100