Normally, the monthly charges for utility-owned safety lighting installed at the request of the State should be shared jointly with the local agency, as above. Where a local agency proposes to install lighting on a State highway, an encroachment permit is required. Lighting may also be installed at the intersection of a State highway and private driveway by a private property owner under an encroachment permit.
Such lighting shall in no way detract from the effectiveness of existing State safety lighting or in any way interfere with the safe movement of traffic. On existing roadways, except expressways or freeways, the lighting may be installed on wood poles with overhead wiring.
On expressways and full freeways, the equipment shall meet State standards, i. Where a local agency proposes to install continuous lighting using luminaires of higher light output than the existing highway safety luminaires, the project should include replacing the existing units with new luminaires with the higher light output.
The State will review the design of such lighting. The installation may be performed by local agency forces, a contractor or an electrical utility.
The State will participate only in the costs of installation or upgrading, maintenance, and operation of safety lighting as warranted in Sections In the event the local agency desires to have the relocated local agency owned lighting system reconstructed to an improved standard as part of a State contract, the difference in cost between replacement in kind and the construction requested shall be estimated and the agency shall agree to reimburse the State for the additional cost.
The reconstruction of existing street lighting facilities owned by a private utility is the responsibility of the utility and will be handled by the Division of Right of Way. When affected by construction on a conventional State highway, existing street lighting facilities owned by a city, county, or lighting district shall be reconstructed at the sole expense of the owner unless prior rights can be established.
In the event a local agency desires to have an existing continuous lighting system along a State highway reconstructed to an improved standard, or a new system built to higher than State standards, the cost to the State shall be limited to its share of the lighting at those locations where safety lighting is warranted. The design of highway safety lighting by the California Department of Transportation Caltrans is based upon the following publications:.
Traffic Manual Caltrans 2. Standard Specifications Caltrans 3. Standard Plans Caltrans 4. Signal and Lighting Design Guide Caltrans. A minimum of two luminaires should be placed at each freeway exit ramp and one luminaire at each freeway entrance ramp.
Typical locations for luminaires at the intersections of freeway ramps and surface streets are shown in Figure PDF. Additional lighting may be installed if ramp traffic meets the following volumes during one hour of darkness:.
Where highway safety lighting is to be in-stalled at intersections on conventional highways, including the intersection of a freeway ramp with a local street , the minimum maintained horizontal illuminance should be as follows: In urban areas and expressways, 1.
In rural areas, 1. To determine the position and number of luminaires needed to provide a desired lighting level or to determine the lighting level achieved by a given pattern of luminaires, the isolux diagram for the luminaire may be used. The lighting level at any point may be approximated by adding the values shown by the isolux curve passing through the point from each contributing luminaire.
Isolux diagrams for the commonly used luminaires are shown in the Standard Plans. These diagrams represent the minimum acceptable values and therefore are appropriate for use with any particular manufacturer is luminaire. Transparencies of these diagrams in various scales are available to facilitate their use. Since these diagrams are based on initial values, a light depreciation factor must be applied to determine the maintained level of lighting.
Some overhead directional signs are illuminated. The sign lighting equipment and installation details are shown in the Standard Plans.
Tunnels should have sufficient illumination during the day so that vehicles inside the tunnel may be seen by approaching motorists.
All interior walls and ceilings of tunnels to be lighted should be painted or tiled in a light color. All concrete surfaces to be painted should have a Class 1 finish.
Tunnels over 90 m long may require lighting in the daytime. Tunnels 30 m to 90 m long normally do not require daytime lighting but interior walls and ceiling should be painted. Conventional night lighting should be installed. Lighting should be considered for all passageways including pedestrian openings through or under falsework.
The faces of all falsework and forms located within or adjacent to the traveled way should be illuminated on the approach sides during the hours of darkness. At locations in the interchange area where a special ramp for buses and a bus stop are provided, a minimum of one luminaire should be provided at the bus stop and at each crosswalk on the freeway ramp.
Lighting of Park-and-Ride Lots is desirable, not mandatory. There may be several legitimate reasons why lighting is not provided, e. The following guidelines should be used in determining the amount of lighting to be installed where it has been determined that we can provide lighting without excessive cost:. Design the lighting to provide 0.
Keep the number of poles and fixtures to the minimum necessary to meet the 0. Lighting standards for installation on State highways will normally be one of the types shown in the Standard Plans. The exception is where a local public agency uses different lighting standards and a has existing lighting that is being replaced due to State highway construction, or b desires the inclusion of their roadway lighting into a State highway project.
See Sections Details for each type of lighting standard are shown in the Standard Plans. Types 15 and 22 standards are used on conventional highways and expressways. Also, they may be used at the intersection of freeway ramps with surface streets. The Type 15 may be used on structures in lieu of a Type 21 standard where a lower mounting height is desired. The mast arm length normally used is 3. The Type 21 standard is used on structures and may be mounted on the barrier railing, on the structure deck or on a retaining wall.
Lengths of 1. Types 30, 31, and 32 standards are used on freeways and in freeway interchange areas. The Type 30 is used where the standard cannot be located further than 5. Normal mast arm length is 4. The Type 31 is available only with a 6.
The Type 32 is available only with a 9. Foundation details and foundation installation details for each lighting standard are shown in the Standard Plans.
Location of foundations shall be as follows:. In general, lighting standards should normally be set as far from the right or left edge of the pavement as conditions permit. Exceptions to this occur in cut or fill sections with slopes steeper than ; foundation locations for these conditions are shown in the Standard Plans. On curved ramps, lighting standards should be located on the inside of the curve.
Normal spacing for Types 21, 22, 30, 31 and 32 standards is 55 m. Normal spacing for Type 15 is 46 m. Typical locations for standards are shown in Figures through On structures and retaining walls, lighting standards should be located at least 1. Care should be taken in locating electroliers on lower roadways or structures so as not to be a glare source to vehicles on a higher structure. Exceptions to this policy are that slip bases are not used under lighting standards upon which signals are mounted or under lighting standards located:.
Where pedestrians would be close enough to be endangered by a pole knockdown. Normally, the luminaire for a new installation of safety lighting on State highways is a full-cutoff type using a high pressure sodium lamp.
On freeways, watt lamps shall be used with 9. On conventional highways and at the intersections of freeway ramps with surface streets, watt lamps shall be used with 9. Utility owned semi-cutoff type luminaires should be provided with glare shields in rural areas. Soffit luminaires are special fixtures either suspended from or flush-mounted into structures to illuminate the roadway under the structure.
They shall be used with 70 or watt high-pressure sodium lamps, depending upon lighting requirements. Normally, the fixtures should not be located over the traveled way on freeways. Wall luminaires are fixtures designed to be surface mounted on vertical surfaces. However, a simple right angle bracket permits mounting them from a horizontal surface such as the bottom slab of a box girder. They are used with the same lamps as soffit luminaires. The design of a traffic signal or highway safety lighting system should provide adequate capacity, both in wire size and conduit size, for the proper operation of the complete system.
In addition, it is important to include adequate capacity in the electrical system to allow maintenance to make repairs safely and promptly. One example of this is the spare conductors that are provided in major conduit runs for a traffic signal. Rigid steel conduit. Rigid steel conduit that has been coated with polyvinyl chloride or polyethylene. Rigid nonmetallic conduit. Liquid tight flexible metal conduit.
Intermediate steel conduit. Flexible nonmetallic conduit. The National Electrical Code limits the portion of the conduit's cross section that can be occupied by conductors to the following:. This will compensate for the large number of conductors, the length of the run and the number of bends.
Table shows the cross-sectional areas of the conduits commonly used in traffic signal installations. Conduits should be run either parallel to or at right angles to the structure girders. Except for sidewalk joints, a conduit expansion fitting should be installed at each structure joint, hinge or abutment where a longitudinal movement of 12 mm or greater may occur. Where a lateral movement of 6 mm or greater may occur, an expansion-deflection fitting should be installed.
The recordings for all webinars are available here. The Manual on Uniform Traffic Control Devices for Streets and Highways , or MUTCD defines the standards used by road managers nationwide to install and maintain traffic control devices on all public streets, highways, bikeways, and private roads open to public travel. The MUTCD, which has been administered by the FHWA since , is a compilation of national standards for all traffic control devices, including road markings, highway signs, and traffic signals.
It is updated periodically to accommodate the nation's changing transportation needs and address new safety technologies, traffic control tools, and traffic management techniques. States must adopt the National MUTCD as their legal State standard for traffic control devices within two years from the effective date.
These hard copies are available for sale. On November 7, , the U. Whenever you see an easy-to-read sign, a bright edgeline marking on a foggy night, the countdown timer at a crosswalk, or a well-placed bike lane, take a moment to reflect on the more than eighty years of progress and innovation that the MUTCD embodies.
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