### **ITEM L-109 AIRPORT TRANSFORMER VAULT AND VAULT EQUIPMENT**

DESCRIPTION

109-1.1 This item shall consist of constructing an airport transformer
vault or a prefabricated metal housing these specifications in
accordance with the design and dimensions shown in the plans. This work
shall also include the installation of conduits in floor and foundation,
painting and lighting of the vault or metal housing, and the furnishing
of all incidentals necessary to produce a completed unit. Included as a
separate part under this item or as a separate item where an existing
vault is to be utilized shall be the furnishing of all vault equipment,
wiring, electrical buses, cable, conduit, potheads, and grounding
systems. This work shall also include the painting of equipment and
conduit; the marking and labeling of equipment and the labeling or
tagging of wires; the testing of the installation; and the furnishing of
all incidentals necessary to place it in operating condition as a
completed unit to the satisfaction of the Engineer.

EQUIPMENT AND MATERIALS

**109-2.1 GENERAL.**

**a.** Airport lighting equipment and materials covered by Federal
Aviation Administration (FAA) specifications shall be certified and
listed under Advisory Circular (AC) 150/5345‑53, Airport Lighting
Equipment Certification Program.

**b.** All other equipment and materials covered by other referenced
specifications shall be subject to acceptance through manufacturer\'s
certification of compliance with the applicable specification when
requested by the Engineer.

**c.** Manufacturer\'s certifications shall not relieve the Contractor
of the Contractor's responsibility to provide materials in accordance
with these specifications and acceptable to the Engineer. Materials
supplied and/or installed that do not materially comply with these
specifications shall be removed, when directed by the Engineer and
replaced with materials, which do comply with these specifications, at
the sole cost of the Contractor.

**d.** All materials and equipment used to construct this item shall be
submitted to the Engineer for approval prior to ordering the equipment.
Submittals consisting of marked catalog sheets or shop drawings shall be
provided. Submittal data shall be presented in a clear, precise and
thorough manner. Original catalog sheets are preferred. Photocopies are
acceptable provided they are as good a quality as the original. Clearly
and boldly mark each copy to identify pertinent products or models
applicable to this project. Indicate all optional equipment and delete
non-pertinent data. Submittals for components of electrical equipment
and systems shall identify the equipment for which they apply on each
submittal sheet. Markings shall be boldly and clearly made with arrows
or circles (highlighting is not acceptable). Contractor is solely
responsible for delays in project accruing directly or indirectly from
late submissions or resubmissions of submittals.

**e.** The data submitted shall be sufficient, in the opinion of the
Engineer, to determine compliance with the plans and specifications.
\[The Contractor\'s submittals shall be neatly bound in a properly sized
3-ring binder, tabbed by specification section.\] The Engineer reserves
the right to reject any and all equipment, materials or procedures,
which, in the Engineer's opinion, does not meet the system design and
the standards and codes, specified herein.

**f.** All equipment and materials furnished and installed under this
section shall be guaranteed against defects in materials and workmanship
for a period of at least \[twelve (12) months\] from final acceptance by
the Owner. The defective materials and/or equipment shall be repaired or
replaced, at the Owner\'s discretion, with no additional cost to the
Owner.

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> **The engineer should specify the form in which submittals are to be
> received and number of copies.**
>
> **The length of time for guarantee of materials and workmanship should
> be as stated in the contract between the owner and contractor and the
> contract special provisions.**

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CONSTRUCTION OF VAULT AND PREFABRICATED METAL HOUSING

**109-2.2 CONCRETE.** The concrete for the vault shall be proportioned,
placed, and cured in accordance with Item P-610, Structural Portland
Cement Concrete, using ¾-inch (18 mm) maximum size coarse aggregate.

**109-2.3 REINFORCING STEEL.** Reinforcing steel bars shall be
intermediate or structural grade deformed-type bars and shall meet the
requirements of ASTM A 615.

**109-2.4 BRICK.** Brick shall conform to ASTM C 62, Grade SW.

**109-2.5 RIGID STEEL CONDUIT.** Rigid steel conduit and fittings shall
be in accordance with Underwriters Laboratories Standard 6 and 514.

**109-2.6 LIGHTING.** Vault or metal-housing light fixtures shall be of
a vaporproof type.

**109-2.7 OUTLETS.** Convenience outlets shall be heavy-duty duplex
units designed for industrial service.

**109-2.8 SWITCHES.** Vault or metal-housing light switches shall be
single-pole switches.

**109-2.9 PAINT.**

**a.** Priming paint for ungalvanized metal surfaces shall be a high
solids alkyd primer conforming to TT‑P‑664D.

**b.** White paint for body and finish coats on metal and wood surfaces
shall be ready-mixed paint conforming to the Master Painter's Institute,
Reference #9, Exterior Alkyd, Gloss, VOC Range E2.

**c.** Priming paint for wood surfaces shall be mixed on the job by
thinning the above specified white paint by adding 1/2 pint (0.06 liter)
of raw linseed oil to each gallon (liter).

**d.** Paint for the floor, ceiling, and inside walls shall be in
accordance with Fed. Spec. TT-E-487. Walls and ceiling shall be light
gray and the floor shall be medium gray.

**e.** The roof coating shall be hot asphalt material in accordance with
ASTM D 2823.

**109-2.10 HIGH-VOLTAGE BUS.** High-voltage bus shall be standard weight
3/8-inch (9 mm) IPS copper tubing or it may be insulated copper cable of
the size and voltage rating specified.

**109-2.11 BUS CONNECTORS.** Connectors shall be similar to Burndy Type
NT (or equivalent) for copper tubing. Connectors for insulated bus cable
shall be of the proper size and type for the service intended.

**109-2.12 BUS SUPPORTS.** Bus supports shall be similar to Westinghouse
No. 527892 (or equivalent), insulated for 7,500 volts, single clamp type
for 2-bolt flat mounting.

**109-2.13 GROUND BUS.** Ground bus shall be 1/8 - x ¾-inch (3 x 18 mm)
minimum copper bus bar.

**109-2.14 SQUARE DUCT.** Duct shall be square similar to that
manufactured by the Square D Company (or equivalent), or the Trumbull
Electric Manufacturing Company (or equivalent). The entire front of the
duct on each section shall consist of hinged or removable cover for
ready access to the interior. The cross section of the duct shall be not
less than 4 x 4 inches (100 x 100 mm) except where otherwise shown in
the plans.

**109-2.15 GROUND RODS.** Ground rods shall be copper or copper‑clad of
the length and diameter specified in the plans.

**109-2.16 POTHEADS.** Potheads shall be similar to G&W Type N, Shape C
(or equivalent), unless otherwise specified. Potheads shall be furnished
with plain insulator bushings and conduit couplings. Potheads shall have
a rating not less than the circuit voltage.

**109-2.17 PREFABRICATED METAL HOUSING.** The prefabricated metal
housing shall be a commercially available unit.

**109-2.18 FAA-APPROVED EQUIPMENT.** Certain items of airport lighting
equipment installed in vaults are covered by individual FAA equipment
specifications. The specifications are listed below:

AC 150/5345-3 Specification for L-821 Panels for Remote Control of
Airport Lighting

AC 150/5345-5 Circuit Selector Switch

AC 150/5345-7 Specification for L-824 Underground Electrical Cable for
Airport Lighting Circuits

AC 150/5345-10 Specification for Constant Current Regulators and
Regulator Monitors

AC 150/5345-13 Specification for L-841 Auxiliary Relay Cabinet Assembly
for Pilot Control of Airport Lighting Circuits.

**109-2.19 OTHER ELECTRICAL EQUIPMENT.** Constant-current regulators,
distribution transformers, oil switches, cutouts, relays, terminal
blocks, transfer relays, circuit breakers, and all other regularly used
commercial items of electrical equipment not covered by FAA equipment
specifications shall conform to the applicable rulings and standards of
the Institute of Electrical and Electronic Engineers or the National
Electrical Manufacturers Association. When specified, test reports from
a testing laboratory indicating that the equipment meets the
specifications shall be supplied. In all cases, equipment shall be new
and a first-grade product. This equipment shall be supplied in the
quantities required for the specific project and shall incorporate the
electrical and mechanical characteristics specified in the proposal and
plans.

**109-2.20 WIRE.** Wire in conduit rated up to 5,000 volts shall conform
to AC 150/5345-7, Specification for L-824 Underground Electrical Cables
for Airport Lighting Circuits, for rubber insulated neoprene-covered
wire, or Fed. Spec. J-C-30, Type RHW, for rubber insulated
fibrous-covered wire. For ratings up to 600 volts, thermoplastic wire
conforming to Fed. Spec. J-C-30, Types TW, THW, and THWN, shall be used.
The wires shall be of the type, size, number of conductors, and voltage
shown in the plans or in the proposal.

**a. Control Circuits.** Unless otherwise indicated on the plans, wire
shall be not less than No. 12 AWG and shall be insulated for 600 volts.
If telephone control cable is specified, No. 19 AWG telephone cable
conforming to ICEA S-85-625-1996 specifications shall be used.

> **b. Power Circuits.**

**(1)** 600 volts maximum-Wire shall be No. 6 AWG or larger and
insulated for at least 600 volts.

**(2)** 3,000 volts maximum-Wire shall be No. 6 AWG or larger and
insulated for at least 3,000 volts.

**(3)** Over 3,000 volts-Wire shall be No. 6 AWG or larger and insulated
for at least the circuit voltage.

CONSTRUCTION METHODS

CONSTRUCTION OF VAULT AND PREFABRICATED METAL HOUSING

**109-3.1 GENERAL.** The Contractor shall construct the transformer
vault or prefabricated metal housing at the location indicated in the
plans. Vault construction shall be reinforced concrete, concrete
masonry, or brick wall as specified. The metal housing shall be
prefabricated equipment enclosure to be supplied in the size specified.
The mounting pad or floor details, installation methods, and equipment
placement are shown in the plans.

The Contractor shall clear, grade, and seed the area around the vault or
metal housing for a minimum distance of 10 feet (3 m) on all sides. The
slope shall be not less than ½-inch per foot (40 mm per m) away from the
vault or metal housing in all directions.

The vault shall provide adequate protection against weather elements,
including rain, wind-driven dust, snow, ice and excessive heat. The
vault shall have sufficient filtered ventilation, to assure that the
interior room temperatures and conditions do not exceed the recommended
limits of the electrical equipment to be installed in the vault.
Contractor is responsible for contacting the manufacturer of the
equipment to be installed to obtain environmental limitations of the
equipment to be installed.

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> **The electrical vault shall provide reasonable protection of the
> equipment that it is intended to house. As most of the equipment
> located in the vault is likely housed in NEMA 1 enclosures, the vault
> itself shall be designed to provide sufficient protection against
> weather elements.**
>
> **Assure that the vault that is to be supplied has sufficient
> environmental controls to provide adequate ventilation to maintain
> temperatures within operational requirements of equipment to be
> installed. In addition, make sure that vault has sufficient seals
> and/or filters on doors and other openings to assure that wind-driven
> dust does not affect operation of equipment.**

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**109-3.2 FOUNDATION AND WALLS.**

**a. Reinforced Concrete Construction.** The Contractor shall construct
the foundation and walls in accordance with the details shown in the
plans. Unless otherwise specified, internal ties shall be of the
mechanical type so that when the forms are removed the ends of the ties
shall be at least 1-inch (25 mm) beneath the concrete surface; the holes
shall be plugged and finished to prevent discoloration. Reinforcing
steel shall be placed, as shown in the drawings, and secured in position
to prevent displacement during the concrete placement.

The external surfaces of the concrete shall be thoroughly worked during
the placing operation to force all coarse aggregate from the surface.
Thoroughly work the mortar against the forms to produce a smooth finish
free from air pockets and honeycomb.

The surface film of all pointed surfaces shall be removed before setting
occurs. As soon as the pointing has set sufficiently, the entire surface
inside and outside of the vault shall be thoroughly wet with water and
rubbed with a No. 16 carborundum stone, or equivalent quality abrasive,
bringing the surface to a paste. All form marks and projections shall be
removed. The surface produced shall be smooth and dense without pits or
irregularities. The materials which have been ground into a paste during
the rubbing process shall be spread or brushed uniformly over the entire
surface (except the interior surfaces that are to be painted shall have
all paste removed by washing before painting) and permitted to reset.
Final exterior finish shall be obtained by rubbing with No. 30
carborundum stone, or an equivalent quality abrasive. The surface shall
be rubbed until the entire surface is smooth and uniform in color.

**b. Brick and Concrete Construction.** When this type of construction
is specified, the foundation shall be concrete conforming to the details
shown in the plans. The outer edge of the foundation at the floor level
shall be beveled 1-½ inches (37 mm) at 45 degrees. Brick walls shall be
8 inches (200 cm) thick, laid in running bond with every sixth course a
header course. Brick shall be laid in cement mortar (1 part masonry
cement and 3 parts sand) with full mortar bed and shoved joints. All
joints shall be completely filled with mortar, and facing brick shall be
back-parged with mortar as work progresses. All joints shall be 3/8 inch
(9 mm) thick, exterior joints tooled concave, and interior joints struck
flush.  Both interior and exterior brick surfaces shall be cleaned and
nail holes, cracks and other defects filled with mortar.  When
specified, a nonfading mineral pigment mortar coloring shall be added to
the mortar. Steel reinforcing bars, 3/8-inch (9 mm) in diameter and 12
inches (300 mm) long, shall be set vertically in the center of the brick
wall on not more than 2-foot (60 cm) centers to project 2-½(60 mm)
inches into the concrete roof slab. Lintels for supporting the brickwork
over doors, windows, and louvers shall consist of two 4‑ x 3‑ x 3/8-inch
(100 x 75 x 9 mm) steel angles. Lintels shall be painted with one coat
of corrosion‑inhibiting primer before installation, and all exposed
parts shall be painted similar to doors and window sash after
installation.

Window sills may be concrete poured in place or precast concrete as
indicated in the plans. All exposed surfaces shall have a rubbed finish
as specified under reinforced concrete construction. After completion,
all interior and exterior faces of walls shall be scrubbed with a
solution of muriatic acid and water in the proportions of not less than
1 part acid to 10 parts of water. All traces of efflorescence, loose
mortar, and mortar stain shall be removed, and the walls washed down
with clear water.

**c. Concrete Masonry Construction.** When this type of construction is
specified, the foundation shall be concrete conforming to the details
shown in the plans. The concrete masonry units shall be standard sizes
and shapes and shall conform to ASTM C 90 and shall include the
closures, jambs, and other shapes required by the construction as shown
in the plans. Standard construction practice shall be followed for this
type of work including mortar, joints, reinforcing steel for extensions
into roof slab, etc. Plaster for interior walls, if specified, shall be
portland cement plaster.

**109-3.3 ROOF.** The roof shall be reinforced concrete as shown in the
plans. Reinforcing steel shall be placed as shown in the drawing and
secured in position to prevent displacement during the pouring of the
concrete. The concrete shall be poured monolithically and shall be free
of honeycombs and voids. The surface shall have a steel-troweled finish
and shall be sloped as shown in the drawing. The underside of the roof
slab shall be finished in the same manner as specified for walls.

One brush or mop coat of hot asphalt roof coating shall be applied to
the top surface of the roof slab. The asphalt material shall be heated
to within the range specified by the manufacturer and immediately
applied to the roof. The finished coat shall be continuous over the roof
surface and free from holidays and blisters. Smears and dribbles of
asphalt on the roof edges and building walls shall be removed.

**109-3.4 FLOOR.** The floor shall be reinforced concrete as shown in
the drawings. When present, all sod, roots, refuse, and other perishable
material shall be removed from the area under the floor to a depth of 8
inches (200 mm), unless a greater depth is specified in the invitation
for bids. This area shall be backfilled with materials consisting of
sand, cinders, gravel, or stone. Fill shall be placed in layers not to
exceed 4 inches (100 mm) and shall be thoroughly compacted by tamping or
rolling. A layer of building paper shall be placed over the fill prior
to placing concrete. The floor surfaces shall have a steel-troweled
finish. The floor shall be level unless a drain is specified, in which
case the floor shall be pitched ¼-inch (6 mm) per foot downward toward
the drain. A ¼-inch (6 mm) asphalt felt expansion joint shall be placed
between floor and foundation walls. The floor shall be poured
monolithically and shall be free of honeycombs and voids.

**109-3.5 FLOOR DRAIN.** If shown in the plans, a floor drain and dry
well shall be installed in the center of the floor of the equipment
room. The dry well shall be excavated 4 x 4 feet (120 x 120 cm) square
and to a depth of 4 feet (120 cm) below the finished floor elevation and
shall be backfilled to the elevation of the underside of the floor with
gravel - which shall all pass a 2-inch (50 mm) mesh sieve and shall all
be retained on a ¼-inch (6 mm) mesh sieve. The gravel backfill shall be
placed in 6-inch (150 mm) maximum layers, and the entire surface of each
layer shall be tamped either with a mechanical tamper or with a hand
tamper weighing not less than 25 pounds (11 kg) and having a face area
of not more than 36 square inches (234 square cm) nor less than
16 square inches (104 square cm). The drain inlet shall be set flush in
the concrete floor. The drain shall have a clear opening of not less
than 8 inches (200 mm) in diameter.

**109-3.6 CONDUITS IN FLOOR AND FOUNDATION.** Conduits shall be
installed in the floor and through the foundation walls in accordance
with the details shown in the plans. All underground conduit shall be
painted with a bituminous compound. Conduit shall be installed with a
coupling or metal conduit adapter flush with the top of the floor. All
incoming conduit shall be closed with a pipe plug to prevent the
entrance of foreign material during construction. Space conduit
entrances shall be left closed.

**109-3.7 DOORS.** Doors shall be metal-clad fireproof class a doors
conforming to requirements of the National Electric Code and local
electrical codes.

**109-3.8 PAINTING.** The floor, ceiling, and inside walls of concrete
construction shall first be given a hardening treatment, after which the
Contractor shall apply two coats of paint as specified below, except
that interior face brick walls need not be painted. The hardening
treatment shall consist of applying two coats of either a commercial
floor hardener or a solution made by dissolving 2 pounds (0.9 kg) of
magnesium fluosilicate or zinc sulphate crystals in 1 gallon (liter) of
water. Each coat shall be allowed to dry at least 48 hours before the
next application. After the second treating coat has dried, the surfaces
shall be brushed clean of all crystals and thoroughly washed with clear
water. Paint for walls and ceiling shall be a light gray color approved
by the Engineer. The floor paint shall be a medium gray color approved
by the Engineer.  Before painting, the surfaces shall be dry and clean.
The first coat shall be thinned by adding 2/3-quart (0.166 liters) of
spar varnish and 1/3‑quart (0.083 liters) of turpentine to each gallon
(liter) of paint. The second coat shall be applied without thinning. All
doors, lintels, and windows shall be cleaned to remove any rust or
foreign material and shall be given one body and one finish coat of
white paint. Bare metal surfaces shall be given a prime coat of
corrosion‑inhibiting primer prior to the body and finish coats.

**109-3.9 LIGHTS AND SWITCHES.** The Contractor shall furnish and
install a minimum of two duplex convenience outlets in the vault room.
Where a control room is specified, at least two duplex outlets shall be
installed.

INSTALLATION OF EQUIPMENT IN VAULT OR PREFABRICATED METAL HOUSING

**109-3.10 GENERAL.** The Contractor shall furnish, install, and connect
all equipment, equipment accessories, conduit, cables, wires, buses,
grounds, and support necessary to insure a complete and operable
electrical distribution center for the airport lighting system as
specified herein and shown in the plans. When specified, an emergency
power supply and transfer switch shall be provided and installed.

The equipment installation and mounting shall comply with the
requirements of the National Electrical Code and local code agency
having jurisdiction.

**109-3.11 POWER SUPPLY EQUIPMENT.** Transformers, regulators, booster
transformers, and other power supply equipment items shall be furnished
and installed at the location shown in the plans or as directed by the
Engineer. The power supply equipment shall be set on steel "H" sections,
"I" beams, channels, or concrete blocks to provide a minimum space of
1-½ inches (37 mm) between the equipment and the floor. The equipment
shall be placed so as not to obstruct the oil‑sampling plugs of the
oil‑filled units; and name-plates shall, so far as possible, not be
obscured.

If specified in the plans and specifications, equipment for an alternate
power source or an emergency power generator shall be furnished and
installed. The alternate power supply installation shall include all
equipment, accessories, an automatic changeover switch, and all
necessary wiring and connections. The emergency power generator set
shall be the size and type specified.

**109-3.12 SWITCHGEAR AND PANELS.** Oil switches, fused cutouts, relays,
transfer switches, panels, panel boards, and other similar items shall
be furnished and installed at the location shown in the plans or as
directed by the Engineer. Wall or ceiling mounted items shall be
attached to the wall or ceiling with galvanized bolts of not less than
3/8-inch (9 mm) diameter engaging metal expansion shields or anchors in
masonry or concrete vaults.

**109-3.13 DUCT AND CONDUIT.** The Contractor shall furnish and install
square-type exposed metallic ducts with hinged covers for the control
circuits in the vault. These shall be mounted along the walls behind all
floor-mounted equipment and immediately below all wall-mounted
equipment. The hinged covers shall be placed to open from the front side
with the hinges at the front bottom.

Wall brackets for square ducts shall be installed at all joints 2 feet
(60 cm) or more apart with intermediate brackets as specified. Conduit
shall be used between square ducts and equipment or between different
items of equipment when the equipment is designed for conduit
connection. When the equipment is not designed for conduit connection,
conductors shall enter the square-type control duct through insulating
bushings in the duct or on the conduit risers.

**109-3.14 CABLE ENTRANCE AND HIGH-VOLTAGE BUS SYSTEM.** Incoming
underground cable from field circuits and supply circuits will be
installed outside the walls of the transformer vault as a separate item
under Item L‑108. The Contractor installing the vault equipment shall
bring the cables from the trench or duct through the entrance conduits
into the vault and make the necessary electrical connections. For the
incoming and outgoing high voltage load circuits, the Contractor shall
furnish and install rigid metallic vi conduit risers, surmounted by
potheads, from floor level to the level as shown in the plans.

The incoming high-voltage power supply service to the vault shall enter
below the floor of the vault and shall rise from the floor level in a
rigid metallic conduit riser, surmounted by a pothead, as described
above. Using insulated high-voltage cable, the incoming power service
shall be connected from the pothead to the oil-fused cutouts or to the
specified disconnecting switch or equipment. From the oil-fused cutouts
or disconnecting device, the insulated service conductors shall be
connected to the overhead voltage bus system of the vault. The
high-voltage bus system shall utilize the materials specified and shall
be mounted and installed in accordance with the requirements of the
National Electrical Code or the local code agency having jurisdiction.

**109-3.15 WIRING AND CONNECTIONS.** The Contractor shall make all
necessary electrical connections in the vault in accordance with the
wiring diagrams furnished and as directed by the Engineer. In wiring to
the terminal blocks, the Contractor shall leave sufficient extra length
on each control lead to make future changes in connections at the
terminal block. This shall be accomplished by running each control lead
the longest way around the box to the proper terminal. Leads shall be
neatly laced in place.

**109-3.16 MARKING AND LABELING.** All equipment, control wires,
terminal blocks, etc., shall be tagged, marked, or labeled as specified
below:

**a. Wire Identification.** The Contractor shall furnish and install
self-sticking wire labels or identifying tags on all control wires at
the point where they connect to the control equipment or to the terminal
blocks. Wire labels, if used, shall be of the self‑sticking preprinted
type and of the manufacturer\'s recommended size for the wire involved.
Identification -markings designated in the plans shall be followed.
Tags, if used, shall be of fiber not less than ¾-inch (13 mm) in
diameter and not less than 1/32-inch (1 mm) thick. Identification
markings designated in the plans shall be stamped on tags by means of
smalltool dies. Each tag shall be securely tied to the proper wire by a
nonmetallic cord.

**b. Labels.** The Contractor shall stencil identifying labels on the
cases of regulators, breakers, and distribution and control relay cases
with white oil paint as designated by the Engineer. The letters and
numerals shall be not less than 1 inch (25 mm) in height and shall be of
proportionate width. The Contractor shall also mark the correct circuit
designations in accordance with the wiring diagram on the terminal
marking strips, which are a part of each terminal block.

METHOD OF MEASUREMENT

**109-4.1** The quantity of vaults to be paid for under this item shall
consist of the number of vaults constructed in place and accepted as a
complete unit.

**109-4.2** The quantity of prefabricated metal housings to be paid for
under this item shall consist of the number of housings constructed in
place and accepted as a complete unit.

**109-4.3** The quantity of vault or prefabricated metal housing
equipment to be paid for under this item shall consist of all equipment
installed, connected, and accepted as a complete unit ready for
operation.

BASIS OF PAYMENT

**109-5.1** Payment will be made at the contract unit price for each
completed and accepted vault or prefabricated metal housing equipment
installation. This price shall be full compensation for furnishing all
materials and for all preparation, assembly, and installation of these
materials, and for all labor, equipment, tools, and incidentals
necessary to complete the item.

Payment will be made under:

Item L-109-5.1 Construction of Airport Transformer Vault in Place-per
unit

Item L-109-5.2 Installation of Airport Transformer Vault Equipment in
Place-per unit

Item L-109-5.3 Construction of Prefabricated Metal Housing and
Foundation in Place-per unit

Item L-109-5.4 Installation of Prefabricated Metal Housing Equipment in
Place-per unit

MATERIAL REQUIREMENTS

AC 150/5345-3 Specification for L-821 Panels for Remote Control of
Airport Lighting

AC 150/5345-5 Circuit Selector Switch

AC 150/5345-7 Specification for L-824 Underground Electrical Cable for
Airport Lighting Circuits

AC 150/5345-10 Specification for Constant Current Regulators and
Regulator Monitors

AC 150/5345-13A Specification for L-841 Auxiliary Relay Cabinet Assembly
for Pilot Control of Airport

> Lighting Circuits

ANSI/ICEA S-85-625-1996 Aircore, Polyethylene Insulated, Copper
Conductor, Telecommunications Cable

ASTM A 615 Specification for Deformed and Plain Billet Steel Bars for
Concrete Reinforcement

ASTM C 62 Specification for Building Brick (Solid Masonry Units Made
from Clay or Shale)

ASTM C 90 Concrete Masonry Units, Loadbearing

ASTM D 2823 Asphalt Roof-Coating

FED SPEC J-C-30 Cable and Wire, Electrical (Power, Fixed Installation)
(cancelled; replaced by AA-59544 Cable and Wire, Electrical (Power,
Fixed Installation))

FED SPEC TT-E-487 Enamel, Floor and Deck

Master Painter's Institute

END OF ITEM L-109