11.4 Equipment
11.4.1 Panelboards (Power and Lighting)
BWI Marshall and MTN Airport projects shall only specify Square-D 120/208 circuit breaker panelboards. Accordingly, “No substitutions will be accepted” shall be used when specifying Square-D circuit breaker panelboards.
11.4.2 Raceways
11.4.2.1 Raceways – Within Buildings
Indoor wiring methods:
A. Exposed where subject to physical damage: Rigid galvanized steel (RGS) conduit from slab up to 10 feet above finished floor. Electrical metallic tubing (EMT) above 10 feet above finished floor.
B. Exposed where not subject to physical damage: EMT.
C. Concealed: EMT
D. Concealed where installing/fishing new wiring in existing wall or partition: Flexible metal conduit (FMC) or metal clad cable (MC). FMC and MC shall be directly connected to junction box located directly above existing wall or partition.
E. Connection to vibrating equipment (Including transformers and hydraulic, pneumatic, electric solenoid, or motor-driven equipment): Liquid tight flexible metal conduit (LFMC) or FMC. Use maximum of 6 foot length. Connections in wet or damp environments shall use LFMC.
F. Final connection to recessed and semi-recessed lighting fixtures: FMC or MC. Use maximum of 6 foot length from fixture to junction box only.
G. Minimum raceway size: Minimum Electrical raceway shall be ¾ inch and Minimum Communications raceway shall be 1 inch.
H. The use of any type flexible raceway or flexible cable other than those specifically mentioned above will not be accepted unless approved in advance.
I. In approved tenant spaces, MC Cable shall be permitted to be used for branch circuit wiring drops and lighting. Daisy-chained wiring is permitted. All home runs shall be installed in conduit from the panel to the main installation area, sleeved and fireproofed through walls and terminated with a junction box. All conduit, junctions, boxes, and device plates shall be properly labeled.
J. All spare and electrical conduits 1” and larger must have a bushing installed.
K. All fittings (couplings, connectors, etc.) for metal conduit shall be steel, set screw or compression type. No malleable of aluminum fittings will be considered.
L. Fittings for all flexible metallic conduits shall be steel T&B Tite-Bite style or equivalent. No malleable or aluminum fittings will be considered.
M. All Conduit Outlet Bodies (LB’s, T’s, etc.) not subject to physical damage must of Iron construction Crouse-Hinds Form 5, 7, 8, or equivalent. No Aluminum will be considered.
N. All Conduit Outlet Bodies and Device Boxes (LB’s, T’s, FS, FD, etc.) installed where subject to physical damage must be of Malleable Iron construction Crouse-Hinds Form 5 or equivalent. No aluminum will be considered.
Cable tray shall be permitted for low voltage communication wiring/cable only. All fire alarm and security related wiring/cable shall be installed in a raceway system as detailed in indoor wiring methods 1 through 8 shown above. Public Address System wiring if used to convey voice messages for public space evacuation, as required by the Office of the Fire Marshal, shall be considered fire alarm wiring and shall be installed in a raceway system and protected in accordance with NFPA 72.
All raceways and cables shall be properly installed and supported in accordance with the National Electrical Code (NEC) and the Code of Maryland Regulations (COMAR). All new construction materials shall be fire retardant. All new wiring/cable shall be plenum-rated. Cable and raceways shall be permanently labeled at a minimum of every 50 feet, at all junction boxes and at all terminations. Label information shall include equipment type/usage, supply panelboard/equipment and circuit number. Wherever old raceways, wiring and/or cables are to be abandoned, they shall be removed.
Metal Conduit Fittings: All fittings, coupling, etc. for metal conduit shall be steel, set screw or compression type. No malleable fittings will be considered.
Grounding: A ground wire properly sized to the largest phased conductor shall supplement all metallic conduits. Ground wire shall be identified by either green insulation coating or by the use of green tape.
11.4.2.2 Raceways – Underground
Marking tape indicating “Electrical Cable Buried Below” shall be installed. The tape should be 3” wide and positioned 8”-12” deep below top of ground, or 4” wide and positioned at a maximum 3”-6” deep below the bottom of pavements.
11.4.2.3 Raceways – Labeling
A. All labels shall be mechanical; no handwritten labels unless otherwise approved.
B. Cable and raceways shall be permanently labeled at a minimum of every 50 feet, every 25 feet when view is obstructed, and within 5 feet of any wall or floor/ceiling penetration at all junction boxes, terminations, and within 12 inches of electrical panel.
C. The area to be labeled shall be cleaned prior to labeling.
D. Labeling shall include: Type/Usage, Panelboard/Equipment, Circuit Number
E. For labeling requirements of installations consisting of multiple systems occupying the same space, see Chapter 11.4.2.4 Raceways – Voltages.
F. Wall switches, receptacles, occupancy sensors, wall dimmers, device plates and box covers, poke-through fittings, access floor boxes, photocells, time clocks, and other similar outlets shall be identified externally with circuit numbers and source. In areas exposed to the public, identifications should be made on the back side of device covers. Use machine-generated labels or neatly, handwritten permanent marker.
G. All Panelboard circuit directories shall be updated and mechanically generated. No handwritten updates or changes shall be made.
A. Wiring derived from different system voltages of 50V-600V shall be installed in separate conduits. Cables and conductors shall not occupy the same installation space (i.e. cable tray, metal wireways, compartment, enclosure, manhole, outlet box, device box, raceway, or similar fitting) unless critical to the operation of installed equipment (motor starters, relays, contactors, etc.).
Exception #1: Wiring of different voltages may be permitted to be installed in the same junction box provided that a barrier is installed to separate the voltages.
Exception #2: Wiring of different voltages may be installed in cable tray and metal wireways (troughs) provided that the raceway is labeled “Multiple Voltages Present” at no more than 6’ intervals when installed above a suspended ceiling, under a raised floor, or similar location and no more than 15’ where installed elsewhere. Labeling shall be sized to ensure visibility from any access point.
B. Class 2 and 3 cables shall be permitted to share the same raceway as 50V-600V wiring when in compliance with NEC 725.55.
C. No wiring other than the primary voltage indicated shall be installed in electrical panels.
D. Wiring color code shall be standardized as follows:
120/208, 120/240 Black, Red, Blue and White
277/480 and higher Brown, Orange, Yellow, and Gray
11.4.2.5 Raceways – Workmanship
A. Neat and Workmanlike Manner: Executed and/or installed in a skilled manner; e.g., plumb, level, square, in line, undamaged and without marring adjacent work. Conduits shall be run parallel to and/or perpendicular to the building structure.
In addition, Electrical work should be installed in accordance with ANSI/NECA 1-2006: Standard for Good Workmanship in Electrical Construction.
B. Conduits shall be supported within 2 feet of the beginning of a 90° bend or offset.
C. Performance of Work - All electrical work performed shall be under the direction of a master electrician licensed in the State of Maryland or in the county where the work is performed. In addition, all electrical work shall be performed by or under the direct supervision of a Journeyman electrician.
11.4.3 Receptacles
11.4.3.1 Electrical Receptacles in Offices, Other Spaces and Non-Public Corridors
Duplex receptacles shall be rated at 20 amperes, 125 volts, and be polarized, parallel blade type with ground and National Electrical Manufacturer's Association (NEMA) 5-20R configuration. Receptacles equivalent in quality to Pass & Seymour (P&S) Catalog number 5362, heavy duty specification grade, should be specified. The receptacles shall be side wired.
11.4.3.2 Electrical Receptacles in Airport Terminal Public Corridors, Ticketing Areas, and Baggage Claim Areas
Receptacles for these, and other areas subject to heavy use by housekeeping and cleaning machinery, should be equivalent in quality to Pass & Seymour (P&S) Catalog number 5362A, extra heavy duty. Receptacles shall be side wired, and spaced no more than 100 feet apart. These receptacles shall be placed on dedicated circuits, that is, they shall be isolated from receptacles in other types of spaces. In addition, no more than two receptacles shall be placed on the same circuit.
11.4.3.3 Cover Plates for Receptacles
Cover plates for receptacles shall be brushed stainless steel. Receptacles shall be identified by color-coding the face and body according to type of circuit they are connected to, per the following:
A. Regular Power – Brown or Ivory
B. Uninterruptible Power Supply (UPS) – Red
C. Isolated Ground – Orange/or Ivory with Orange Triangle
11.4.4 Charging Stations
11.4.4.1 Charging Stations - General
The purpose of this section is to define parameters for the installation of charging stations for personal electronic devices in common use hold rooms and public spaces within the airport terminal. The intent of the standard is to provide adequate and convenient charging stations for use by the traveling public. Ultimate layouts for charging stations will be on an installation by installation basis but must provide the charging station types and density prescribed.
11.4.4.2 Charging Station – Types
A mixture of duplex receptacles and 5v USB receptacle will be provided. Duplex receptacles for charging stations will meet the requirements of Chapter 11.4.3.1 Electrical Receptacles in Offices, Other Spaces and Non-Public Corridors. Electrical Receptacles in offices, other spaces, and Nonpublic Corridors. Induction type charging stations can be utilized for one third (1/3) of the positions required in Chapter 11.4.4.3 Charging Station – Density.
Stations can be for either standing or seating in a chair or stool. They should discourage sitting on the floor.
A. Standing stations
Each standing/wall mounted station will include both receptacle types and a shelf or counter surface suitable for writing or supporting a laptop computer. Standing stations shall be located so as not to impede general pedestrian circulation, restrict egress pathways, and be ADA compliant.
B. Sitting Stations
Sitting stations will include both receptacle types and will be either mounted directly on the furniture or on a wall receptacle at a height that provides convenient access from the associated seating. Furniture mounted units will be in ‘InFlex’ system by Acronas or an approved equal. Receptacles mounted on seating that is not located against a wall will be powered by recessed floor mounted receptacles. Cords from these receptacles will be managed and will not be readily accessible or pose a tripping hazard. Wall outlets providing power for adjacent seating stations should be positioned below the back of the seating to discourage disconnecting the power cords.
11.4.4.3 Charging Station – Density
A. Hold Rooms
Charging Stations will be installed with a duplex receptacle for every two hundred (200) square feet and one USB outlet per every five hundred (500) square feet of hold room as defined in the Space Allocation Plan. New installations requiring freestanding seating with floor mounted outlets will require seating plans to be reviewed and approved by the MDOT MAA Office of Engineering & Construction and the Office of the Fire Marshal.
B. Public Areas
Charging Stations in corridor areas will be installed with two (2) duplex receptacles and four (4) USB receptacles per three hundred (300) linear feet of corridor. Charging Stations in public lounge areas will be installed at the same density as hold rooms.
Charging Stations in other public areas will be installed on an installation by installation basis.
11.4.4.4 Charging Stations – New Construction in Terminal
All new terminal construction shall be designed to include charging stations. Designs shall meet the charging station density requirements and provide all required infrastructure including adequate power supply. Charging station types and locations shall be approved by the MDOT MAA.