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As specified in the Contract Documents. Welded wire fabric as specified in 908.05.
Provide retroreflective sheeting that meets the requirements of the latest version of ASTM D4956 and is selected from the Administration’s Qualified Products List QPL. The type of sheeting to be used for different classifications of signs shall be as specified in the QPL and as described below.
Provide fluorescent colors, when yellow, orange or pink sheeting is specified. Color coordinates and values shall be as described in the MDMUTCD and 23 CFR Part 655, Subpart F, Appendix.
Provide non-reflective sheeting, when black sheeting is specified.
All sheeting for legend and backgrounds shall be from the same manufacturer and be a matched component system intended to be used together.
Use ASTM Type IV or VIII construction sheeting with a Class 1 backing for drums for maintenance of traffic. The sheeting must be reboundable as defined in the supplementary requirements of ASTM D4956, latest version.
Use ASTM Type IV, V or VIII for delineators, and lane separator systems. Use ASTM Type IV, VI or VIII sheeting for cones for maintenance of traffic. The sheeting must be reboundable as defined in the supplementary requirements of ASTM D4956, latest version.
Use ASTM Type VI sheeting with a Class 5 backing for Roll up signs for Maintenance of Traffic.
Use ASTM Type VIII, IX or XI sheeting for rigid temporary traffic signs.
Use ASTM Type IX or XI sheeting for Guide Signs, Exit Gore Signs, General Information Signs, School Signs, Warning Signs and Red Regulatory Signs.
Use ASTM Type IV, VIII, IX or XI sheeting for all other Regulatory Signs and for Route Markers.
Use ASTM Type I or higher sheeting for No Trespassing Signs, signs directed at Pedestrian Traffic, signs directed at Bicycle Traffic, R7 series Parking signs, R8 series Parking signs and supplemental panels for R7 and R8 series signs.
Design, material minimum thickness requirements and construction shall meet AASHTO Specifications for Structural Supports for Highway Signs, Luminaires, and Traffic Signals and the following:
(a) A709, Grade 50 for structural steel.
(b) A595, Grade A or API 5LX52 for steel tubes or pipes.
(c) All steel shall be galvanized according to A123.
Hardware, as specified in 909.06, 909.07 and 909.08.
The lower 1 ft depth of trench shall be fine aggregate meeting Section 901. Material above the 1 ft depth shall be select material as specified in Section 916.
A standard commercial product manufactured not more than one year prior to the date of the Contract. All cable and wire shall be made of copper.
950.06.01 Direct Burial Cable. A single conductor stranded, with an unshielded, chemically crosslinked thermosetting polyethylene insulation rated for 600 volts. The cable shall be suitable for direct earth burial or installation in ducts or conduit and shall meet UL Type USE, XHHW or THW and bear the applicable UL labels denoting type, size, stranding, manufacturer’s name and surface marking or molded ridges for phase and neutral identification. Sizes shall be as specified.
950.06.02 Building Cable and Wire. 600 V, plastic insulated, nylon jacketed and shall meet UL Type THWN/THHN and bear the applicable UL labels denoting type, size, stranding, manufacturer’s name and surface marking or molded ridges for phase and neutral identification. Sizes shall be as specified.
950.06.03 Cable Duct. Shall consist of cables preinstalled in either a polyvinyl chloride (PVC) or polyethylene (PE) plastic duct meeting NEMA TC 7 and the NEC. PVC shall meet D3485. PE duct shall be manufactured from black, virgin, high density PE resin meeting D1248, Type III, Grade P34, Class C, Category 5. Minimum inside diameter of duct shall be 1-1/2 in. Cable shall be rated for 600 volts.
950.06.04 Ground Wire and Rods. Ground wire shall be bare medium drawn copper. Ground wire shall be of the size (solid or stranded) configuration shown in the Contract Documents. Ground rods shall be 0.75 in. diameter, a minimum of 10 ft in length, with a steel core and copper jacket.
950.06.05 Traffic Signal Cable. According to IMSA Specification 19-1, Conductors shall be stranded No. 14 AWG.
950.06.06 Loop Detector Lead-In Cable. According to IMSA Specification 50-2. Shall be two conductor, No. 14 AWG, PE jacketed.
950.06.07 Loop Detector Wire. Single conductor, 600 V, No. 14 AWG, 19 strand wire in a flexible PE tubing.
950.06.08 Voice Grade Communication Cable. Self-supporting cable shall be solid No. 19 AWG and meet IMSA specification 40-4. Underground cable shall meet IMSA specification 60-2.
950.06.09 Electric Service Wire. Electric service wire for traffic signals, intersection control beacons, hazard identification beacons, and luminaires mounted on traffic signal structures shall have three individual wires. Each wire shall be seven stranded. Electric service wire color identification by spray paint, tape, heat shrink tubing, or any other after manufacturing method is prohibited.
According to AASHTO Standard Specifications for Structural Supports for Highway Signs, Luminaires, and Traffic Signals, based on 90 mph wind loads, luminaire weight of 70 lb and luminaire projected area of 3 ft2.
Ground mounted lighting structures consist of a one piece, round tapered shaft, a cast steel anchor base for steel structures and a cast aluminum base for aluminum structures, bracket arms, complete with all necessary accessories including anchor bolts, pole top, shims, grounding lug, and handhole.
Steel shafts shall meet A595, Grade A. After forming and welding, the shaft shall have a smooth finish with only one longitudinal weld and no transverse welds. Steel bracket arms and mounting brackets shall meet A53, Schedule 40. Structures shall be either mechanically or hot-dipped galvanized. The coating shall meet the thickness, adherence, and quality requirements of A123.
Aluminum shafts and bracket arms shall be spun from one piece of extruded tubing meeting B241, 6000 T6 series alloy. The shaft and bracket shall be cold worked to form the required taper.
Each lighting structure shall be provided with a permanent 2 x 4 in. tag fabricated from clear anodized 1/16 in. thick aluminum. The edge shall be smooth with rounded corners and the tag shall fit the lighting structure shaft. Tags shall be secured to shafts by means of four 1/8 in. diameter 18-8 stainless steel round head drive screws or self-tapping screws. The identifying letters or numerals as specified.
950.08 SIGNS
TC-1.03. The manufacturer or supplier shall furnish certification as specified.
950.08.01 Sheet Aluminum Sign Panels. B209, with an anodized mill finish. Alloys shall be either 6061 T6 or 5052-H38.
950.08.02 Extruded Aluminum Sign Panels and Edge Strip. B221, alloy 6063 T6.
950.08.03 Hardware. Sign hardware shall be clear anodized and meet one of the following.
(a) B209, alloy 2024 T4 or,
(b) B211, alloy 2024 T4, 6262 T9, 6061 T6, 7075 T6 or 2017 T4.
(a) .01 Span. A475, Grade: Siemens-Martin, Class C, 3/8 in. diameter and seven wire strand.
(b) .02 Tether. A475, Grade: Siemens-Martin, Class C, 1/4 in. diameter and seven wire strand.
950.10 CONDUIT
As specified in Section 805 and 921.07.
Consists of one layer of aluminum foil laminated between two layers of inert plastic film. The foil shall be 3 in. wide with a tensile strength of 60 lb. The plastic film shall have a minimum thickness of 4.5 mil.
A complete lighting device consisting of a housing, support clamp, reflector, refractor or flat lens, socket, lamp, integral ballast, terminal block, associated hardware, and necessary wiring. All parts of the luminaire shall incorporate the latest ratings and design improvements. Luminaires shall incorporate individual twist lock photoelectric cells when specified. Exposed hardware shall be stainless steel.
A Light Emitting Diode (LED) Roadway Luminaire shall be a complete lighting device consisting of a cast aluminum housing, LED arrays, LED drivers, terminal blocks, integral transformer, associated hardware, all necessary wiring, and an optical assembly. Each LED Roadway Luminaire shall have a NEMA 3-prong twist lock photo control receptacle and shall be furnished with a shorting cap.
950.12.01 Luminaire Construction.
(a) Bracket arm mounted luminaire housing shall be cast aluminum with natural finish. The housing shall contain and support the reflector, refractor or flat lens, socket, ballast, terminal block, and support clamp. Provisions shall be made for leveling and adjusting the luminaire to the specified transverse and longitudinal position to the roadway.
The refractor or flat lens retaining ring shall be securely latched with an operable hinge made from noncorrodible material.
The reflector shall be of specular polished alzak aluminum or equivalent aluminum reflective surface and be held firmly in the housing but easily removed without the use of special tools. Silicone rubber, ethylene propylene terpolymer, dacron felt gaskets, or other gasketing materials as approved by the Engineer, shall seal the optical assembly at the socket entry and between the refractor and reflector to make a dust tight optical system. The reflector shall be clean and free from scratches.
Glass for the refractor or flat lens shall be heat resistant, borosilicate glass and shall be free of imperfections. The optical system of the luminaire shall clearly indicate the street side and curb side.
The socket shall be a mogul screw shell with large center contact spring providing a firm contact with the lamp base and have lamp grips to prevent the lamp from loosening. The shell shall be of the skeleton type or shrouded in porcelain. The contacts shall be identifiable. Socket extension adapters will be permitted for special applications when directed. Luminaires providing various ANSI/IES type of distribution by socket adjustment shall also include a means of identification to associate each lamp position with each distribution type. The socket adjustment shall provide positive positioning by means of index holes, lugs, or notches. Slots with infinite settings are prohibited.
The ballast shall be a high power factor, auto regulator type, capable of operating from a multiple circuit and shall operate a high intensity discharge lamp of the type, wattage, and voltage specified. Multitap ballasts shall be provided where supply voltage is 277 volts or less. The ballast shall start the lamp at temperatures as low as -20 F, and shall deliver rated lamp current at circuit voltage variation of plus or minus 10 percent. The primary power factor shall not be less than 90 percent with normal secondary load. The ballast assembly shall be provided with plug in connectors and installed on a hinged door to permit ready interchange of ballast.
Provide glare shields on luminaires where specified or as directed. The glare shield shall cut off the upward component of light but shall not reduce the total output of the luminaire more than 3 percent.
(b) Bridge underpass luminaires shall be a complete lighting device, consisting of a cast aluminum housing, a door with cast aluminum frame, and thermal shock resistant glass refractor attached to the frame with a stainless steel latch, hinges and retaining chain, a specular polished alzak aluminum reflector, a shrouded adjustable porcelain socket, and an integral ballast as specified above. The refractor and reflector shall direct all useful light well below all normal driver viewing angles to ensure that glare will be at a minimum.
(c) Sign lighting luminaires shall be of the type specified in the Contract Documents. The refractor shall be permanently sealed to the door assembly with silicone adhesive around its perimeter. The reflector shall be a single piece dieform of sheet aluminum alloy 3002 or as approved, processed to Alcoa Class SI alzak finish. A heavy duty mogul lampholder shall be securely mounted to the reflector with a galvanized steel bracket. The refractor/door assembly shall be nonpermanently sealed to the luminaire housing and reflector assembly with a single piece neoprene gasket to effectively seal the luminaire and locked in place by stainless steel spring-loaded latches. The refractor/door assembly shall open and be held captive by double pivot internally mounted stainless steel hinges, and shall be removable.
Weepholes shall be provided in the bottom of the housing in the lowest area of the luminaire as normally mounted.
The sign lighting luminaire shall be designed to properly illuminate the sign with the lamp source type and size as specified in the Contract Documents. The Contractor shall submit for the approval, working drawings showing locations and aiming angles of luminaires with relation to each of the signs of the various sizes.
(d) Design LED bracket arm mounted Luminaires for an operational life of at least eleven years with 70 percent lumen maintenance value of 50 000 hours (L70) at an average operating time of 12 hours per night. The illuminance shall not decrease by more than 30 percent over the minimum operational life of eleven years. All components of the LED Roadway Luminaires must be rated for the full service life without maintenance.
Provide LED Roadway Luminaires that use no more than 280 watts and are designed to operate at all voltages from 120 volt to 480 volt. For 480 volt operation, an integral transformer shall be provided to reduce the voltage. The power factor of the LED Roadway Luminaire shall be 0.90 or higher. The Correlated Color Temperature (CCT) shall be less than 4500 K and the Color Rendering Index (CRI) shall be greater than 65.
All components of the LED Roadway Luminaire shall be UL approved. The LED Roadway Luminaire housing and lens/refractor shall be sealed to prevent intrusion of moisture for the full service life and comply with Ingress Protection Rating IP-65 or greater. The lens/refractor shall be constructed of a material that will not show visible yellowing due to UV exposure, or exposure to hydrocarbon emission, for the full service life.
Provide LED Roadway Luminaire drivers that are Solid State (electronic) type with an input voltage range from 120-277VAC (±10 percent), maximum rated output current of 530mA (±5 percent), input frequency of 60Hz, minimum power factor of 90 percent at full load, Total Harmonic distortion less than 20 percent, case temperature rated for -40 C to 50 C, and contain 3 kV input high voltage surge protection.
LED Roadway Luminaire on board circuitry shall include a Surge Protection Device (SPD) to withstand high repetition noise transients as a result of utility line switching, nearby lightning strikes, and other interference. The SPD shall protect the luminaries from damage and failure for transient peak voltages up to 10kV and transient peak currents up to 10kA.
Complete all photometric testing of the LED Luminaires as specified in IESNA technical memorandums LM-63, LM-79 and LM-80. Perform all testing and calculations using photopic values. No correction for scotopic values will be permitted.
Design the LED Roadway Luminaire to mount on a standard tenon mount. No field adjustment, except for leveling, shall be required for installation. All hardware shall be stainless steel.
For placement on the Qualified Product’s List, the product evaluation application must be submitted on the Administration’s Maryland Product Evaluation List (MPEL). After submittal, a minimum of 2 luminaires must be provided for evaluation. The Luminaires will be evaluated for 90 days, and returned to the supplier, if desired. The evaluation will be for general durability and suitability of the luminaires. All shipping costs will be the responsibility of the supplier.
950.12.02 Lamps shall be provided for luminaires of the type and wattage specified. Lamps shall be first line, high quality and be as approved. Lamp wattage, horizontal or vertical initial lumens, rated lamp life, and percent of initial lamp lumens at end of rated lamp life shall be as specified or as follows:



LIFE (10hr/start)



Deluxe Mercury 175 8600 24000 74
Deluxe Mercury 250 12100 24000 74
Deluxe Mercury 400 22500 24000 60
H.P. Sodium 100 9500 20000 74
H.P. Sodium 150 16000 24000 74
H.P. Sodium 200 22000 24000 72
H.P. Sodium 250 30000 24000 73
H.P. Sodium 310 37000 24000 72
H.P. Sodium 400 50000 24000 73
Metal Halide 250 20000 10000 80
Metal Halide 400 40000 15000 80
Refer to section 950.12.01(d) for required lamp wattages and rated lamp life for LED Roadway Luminaires.
950.13.01 Circuit Breakers. Molded case type having a minimum rating of 10 000 amp interrupting capacity (AIC) and be quick make, quick break, thermal magnetic, trip indicating, and have common trip on all multiple breakers with internal tie mechanism. They shall have the current and voltage ratings and number of poles as specified in the Contract Documents, and be treated to resist fungus and be ambiently compensated for the enclosure and proximity to adjacent breakers. All circuit breakers shall be the bolt in type.
950.13.02 Photoelectric Controls. Solid state, cadmium sulfide type with hermetically sealed silicone rectifier rated 120 V, 60 cycle AC and 1000 watts maximum load. Built in surge protection shall be provided, and a fail safe operating feature shall be included so that the lighting circuits will remain energized in the event the photo control components become inoperative. Nominal operating levels of this control shall turn on at a minimum vertical illumination value of 3 ft-c and turn off at a maximum vertical illumination value of 6 ft-c. These limitations shall be set by the manufacturer, and tolerances of plus or minus 20 percent for the specified value will be acceptable.
Photoelectric controls for luminaires and lighting controls shall be twist lock type. A suitable mounting bracket with locking type receptacle and all other necessary mounting hardware shall be furnished.
950.13.03 Contactors and Relays. Contactors of the current ratings and number of poles specified. They shall be fully rated for all classes of load to 600 V and shall have an interrupting rating of 600 percent of rated current. A HAND-OFF-AUTOMATIC selector switch shall be provided in the photoelectric cell circuit. Relays shall be the type, size, and contact ratings as specified.
950.13.04 Panel Boards. Federal Specification W-P-115 and shall be suitable for operation on the voltage and type service specified. They shall be UL listed and labeled. Panel boards shall be equipped with the number and size circuit breakers specified. Circuit breakers in panel boards shall meet Federal Specification W-C-375 and shall be bolted to copper busses. Buss ratings shall be as specified.
950.13.05 Lightning Arresters. Shall be secondary type, having the specified number of poles and 0 to 650 V RMS. Arresters shall be provided with suitable mounting brackets and all other necessary mounting hardware.
950.13.06 Control Power Transformers. Control power transformers shall be the dry type, two windings, of the size and voltage ratings specified.
950.13.07 Enclosures. Shall meet the NEMA type specified and be dead front type weatherproof metal enclosed self-supporting structures, as specified. Free standing enclosures shall be fabricated from sheet aluminum and be as specified herein. Panel and control equipment cabinets shall be the manufacturer’s standard enclosure for the type and application specified. They shall have door clamps, solid neoprene gaskets, welded seams, stainless steel external hardware, and continuous hinges with stainless steel pins. Enclosures shall have two weep holes in the bottom and shall be equipped for padlocking.
950.13.08 Pad Mounted Enclosures. For ventilation, all cabinets shall be provided with louvered vents in the front door with a removable air filter.
(a) Louvers shall meet the NEMA Rod Entry Test for 3R rated ventilated enclosure.
(b) Filters for all cabinets shall be 16 in. long, 12 in. wide and 1 in. thick. The filter shall cover the vents and be held firmly in place with top and bottom brackets and a spring loaded upper clamp.
(c) Exhaust air shall be vented out of the cabinet between the top of the cabinet and the main access door. The exhaust area shall be screened with a material having a maximum hole diameter of 1/8 in.
950.13.09 Thermostats and Fans. A thermostatically controlled cooling fan shall be provided for all cabinets. The fan and thermostat shall be rated for 125 percent of capacity and shall be mounted at the top of the cabinet.
(a) Thermostats shall be the inline type, single pole, 120 V, 10 amps with a minimum range of 40 to 80 F.
(b) The fan shall have a minimum rated capacity of 100 CFM air flow and a minimum rated design life of 100 000 hours.
(c) The thermostat shall be manually adjustable, within a 10 degree range, from 70 to 160 F.
950.13.10 Disconnect Switches and Utility Connections. NEMA standard KS 1-1990. Disconnect switch enclosure shall be Type 4 stainless steel, with external operating handle, enclosure cover interlock, and external switch mechanism handle with provisions for securing in both the ON and OFF positions by padlock. The switch mechanism shall be of heavy duty design with quick make, quick break type operations, and visible blades.
The disconnect switch shall be fusible with integral fuse puller. Single phase disconnect switches shall have 2 poles with a solid neutral and shall be rated at 240 V. Three phase disconnect switches shall have 3 poles with a solid neutral and shall be rated at 600 V. The design of the neutral bar may be factory or field installable.
Disconnect switch fuseholders for traffic signals, intersection control beacons, and intersection lighting operating at 120 V shall be single phase 60 amps (fused 35 amps).
Disconnect switch fuseholders for hazard identification beacons and luminaires mounted on traffic signal structures operating at 120 V shall be rated single phase 30 amps (fused 20 amps).
Disconnect switches for lighting control cabinets shall have the same number of poles and amperage rating specified in the electrical service equipment item.
Disconnect switches for electrical service distribution cabinets shall be 200 amp, 2 pole, and single phase.
950.14.01 Cable Connectors and Connector Kits. For use in lighting structures, hand holes, junction or pull boxes, and for terminating underground cables in lighting structures shall be rated for a minimum of 600 V service. Cable connectors shall be compression type, applied by means of a compression tool. Connectors shall be fabricated from high strength copper alloy. Plated connectors fabricated from metals other than copper are prohibited. Bolted type connectors shall be utilized for splicing bare ground conductors.
950.14.02 Connector Kit Components. Each cable connector kit shall be furnished with all component parts described under the various listed types. Each kit shall contain sufficient silicone compound to lubricate metal parts and the housing for each assembly along with complete installation instructions.
(a) All housings shall be made of water resistant synthetic rubber suitable for burial in the ground or exposure to sunlight. Each housing shall form a watertight seal around the cable at the point of disconnection and between the insert body and enveloping Y housing.
(b) All copper pins, sockets, and fuse contacts shall have a minimum conductivity of 90 percent. The crimpable portion shall be fully annealed while the rest of the device is maintained in its original state.
(c) Plastic sleeves shall be rigid, molded insulating plastic material of sufficient outside diameter to form a watertight fit with its related housing. Wall thickness shall be 0.10 in. maximum, and sleeve lengths of 4 and 7 in. shall be available.
(d) All fuses shall be rated 600V, 100 000 amps AIC.
950.14.03 Connector Types. Each cable connector kit furnished shall be one of the following types:
(a) Type I - Unfused, quick disconnect inline connector kit containing:
(1) A copper pin crimpable to a conductor.
(2) A receptacle having a centrally located, recessed locking socket constructed so that it is filled and retained by its housing and a disposable assembly pin.
(3) A plug housing for retention of the copper pin.
(4) A receptacle housing with disposable protective sleeve.
(b) Type II - Fused, quick disconnect inline connector kit containing:
(1) A pair of spring loaded copper fuse contacts suitable for gripping the specified cartridge fuse. One contact shall be crimpable on a conductor and after insertion into its proper position within the load side plug housing, be capable of being securely retained therein. The other contact shall be preassembled for retention within the line side of the connector body.
(2) A load side housing permanently marked “Load Side”.
(3) A disposable assembly pin.
(4) A fuse of the specified amp rating.
(c) Type III - Fused, quick disconnect Y connector kit containing:
(1) A pair of spring loaded copper fuse contacts suitable for gripping the specified cartridge fuse. One contact shall be crimpable on a conductor and after insertion into its proper position within the load side plug housing, be capable of being securely retained therein. The other contact shall be preassembled for retention within a Y insert body.
(2) A line side Y housing with two water seal cable ports.
(3) Two terminal lugs, each having a mounting hole.
(4) A bolt and a self-locking nut.
(5) A Y insert body with preassembled line side fuse contact and a ring tongue terminal.
(6) A load side plug housing permanently marked “Load Side”.
(7) A disposable assembly pin.
(8) A fuse of specified amp rating.
(d) Type IV - Unfused, quick disconnect Y connector kit containing:
(1) A copper pin crimpable to a conductor and suitable for retention in the load side receptacle housing.
(2) A Y insert body with preassembled load side copper socket and ring tongue terminal.
(3) A line side Y housing with two water seal cable ports.
(4) Two terminal lugs, each having a mounting hole.
(5) A bolt and self-locking nut.
(6) A load side receptacle housing.
Pedestrian signal indications and vehicular signal heads shall meet the Institute of Transportation Engineers (ITE) Specifications.
(a) All materials shall be clean, smooth, and free from flaws, cracks, blowholes, and other imperfections.
(b) Signal heads shall be furnished with the section assembled together including all hardware as specified in the Contract Documents.
(c) All metallic signal head hardware shall be stainless steel material.
(d) Vehicular, optically-programmed and pedestrian signal heads shall be capable of mating to the same type of the signal heads from either the top or bottom of each housing.
(e) All hardware furnished shall be installed on the corresponding fitting and threaded component.
Mounting hardware shall meet the following:
*Using AMS-STD-595A, the signal head housing shall be yellow meeting Color Chip No. 13538. The signal head door and visor shall be optical flat (dull) black, Color No. 37038. Aluminum signal heads shall be painted using fusion bonded polyester coating method.
1 Aluminum Alloy - Casting A319 A380 A713 6063 T6
2 Yield Strength, ksi 18 23 25 25
3 Tensile Strength, ksi 27 47 35 30
4 Brinell Hardness 70 80 75 73
5 Elongation (% in 2 in.) 1.5 4 3 12
6 Stainless Steel A316
7 Galvanized Steel A157 A153 G60
8 Steel-Flat Sheet 16 gauge
9 Coating * Anodized Finish
Hub plate shall meet A, 1 thru 5 and 9B.
(a) Span wire hanger clamp shall meet C, 1 thru 5.
(b) Balance adjuster shall meet 6A, 7A, and 7B.
(c) 2-way lower arm shall meet 7C and 8A.
(d) 2-way tri-stud arm shall meet A, 1 thru 5.
(e) Span wire entrance fitting shall meet C, 1 thru 5.
(f) Mast arm mount signal bracket (1-way, 2-way, and 5-section) shall meet 1A and 1D.
(g) Side pole upper and lower arm assembly shall meet 1B thru 5B or 1D thru 5D.
Vehicular Signal Heads and Pedestrian Signal Indications Housings and Doors.
(a) Aluminum signal head housings and doors shall be die-cast aluminum as specified in the ITE Vehicle Traffic Control Signal Head Specification.
(b) Dual hinge-latch mechanisms shall be mounted on the signal head housing and not the signal head door.
Captive door latch mechanisms (one for 8 in. and two for 12 in. vehicular signal heads, and one for 9 in. and two for 12 in. pedestrian signal indications) shall secure the door to the housing by use of stainless steel eyebolts and wing nut assemblies.
(c) All openings to the housing interior shall be provided with a gasket meeting the physical properties listing in UL 508 and that forms a weather tight seal.
(a) Visors shall be as specified in the ITE Vehicle Traffic Control Signal Head Specification and shall be tunnel type. Visors shall be 10 in. deep for 12 in. vehicular signal heads, 8 in. deep for 8 in. vehicular signal heads, 9 in. deep for 12 in. pedestrian signal indications, and 9.5 in. deep for optically programmed signal heads.
(b) Visors shall be secured to the signal head door by a minimum of four screws mounted perpendicular to the face of the signal head door.
(c) Visors for aluminum vehicular signal and pedestrian signal sections shall be made from aluminum alloy sheet. Visors for polycarbonate signal sections shall be either formed from sheet plastic or assembled from one or more injection, rotational, or blow-molded polycarbonate sections.
Optical System. Vehicular and pedestrian traffic control signal indications shall meet the following.
(a) Signal Head Lamps. Approved by the Office of Traffic and Safety.
(b) Reflector. Shall be made of aluminum.
Reflector support assembly shall be die cast aluminum, separate from the reflector and fully encompass the periphery of the reflector.
Reflector support assembly shall be spring hinged to allow access to the rear of the signal head main body without the use of tools.
(c) Lens. Shall be standard (ball) red, yellow, or green, or specified arrow red, yellow, or green traffic signal lens.
The lens shall be glass.
Directional arrow lenses shall have the same brilliance, regardless which direction they are positioned in the signal face.
The lens shall fit into a one-piece slotted neoprene lens gasket designed to provide a weather resistant fit to the housing door. Lenses shall be secured by a flat clip/screw design fastened from the inside of the signal head door perpendicular to the face of the door. The flat clip/screw design shall not pass through the lens itself.
All pedestrian signal heads shall provide the messages of “walk” and “don’t walk” in the international walking person and the raised hand symbols.
Optical System for Optically Programmed Signal Heads.
(a) The indication from the lens shall meet the requirements of ITE transmittance and chromaticity standards.
(b) Optically programmed signal heads shall have an optical system containing a color filter, lamp fixture, lamp collar, optical limiter/diffuser, and objective lens.
(c) Lamp fixtures shall be comprised of a separately accessible housing and integral lamp support, indexed ceramic socket, and self-aligning and quick release lamp retainer. Electrical connection between case and lamp housing shall be accomplished with an interlock assembly that disconnects the lamp holder when opened.
(d) The optical limiter shall provide an accessible imaging surface at focus on the optical axis for objects 900 to 1200 ft distance and permit an effective veiling mask to be variously applied as determined by the desired visibility zone. The optical limiter shall be composed of heat-resistant glass.
(e) Optically programmed signal heads shall utilize incandescent PAR type lamps. The lamp shall be coupled to the diffusing element. The diffusing element may be discrete or integral with the convex surface of the optical limiter.
(f) The objective lens shall be a high resolution annular incremental lens hermetically sealed within a flat laminate of weather resistant acrylic or as approved by Office of Traffic and Safety. The lens shall be symmetrical in outline and may be rotated to any 90 degree orientation about its axis without displacing the primary image.
(a) The entire signal head assembly shall be either listed or labeled by a Maryland State Fire Marshall or a recognized electrical inspection agency.
(b) Wiring connections at the lamp socket shall lock and not be of the male/female demountable type.
(c) A unitized bail wire with integral spring shall secure the socket to the rear of the reflector. The lamp socket shall have a serrated base to permit locking.
(d) Each single section and the middle section of three section signal heads shall have a minimum of a six section, twelve position terminal block capable of accepting three number 14 AWG spade terminal ends. The top section of two section pedestrian signal indications shall be furnished with a minimum of five section, ten position terminal blocks capable of accepting three number 14 AWG spade terminal ends.
(e) Optically programmed signal heads shall not contain a resistance device for use as an intensity controller with integral means for regulating its intensity between limits as a function of individual background illumination.