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The following criteria are necessary to ensure satisfactory impact performance of

luminaire supports.

• Use only designs that have been approved as crashworthy by the FHWA.

• The FHWA has established upper limits on the support mass and height of luminaire supports. These limits are applicable even when the breakaway characteristics have proven acceptable by crash testing. The maximum acceptable support weight (mass) is 1000 lb (454 kg), and the maximum luminaire support height is 60 ft (18.3 m). These values are increased from the limits of 600 lb (272 kg) and 50 ft (15.2 m) cited a few years ago. Any further increases in these limits should be based on full-scale crash testing and an investigation of vehicle characteristics beyond those recommended in NCHRP Report 350 [13, 19].

• Bre...

Maintenance activities usually fall into one of two categories: demand or routine. Demand-responsive maintenance is response to random occurrences such as luminaire failures—i. e., lamps, fuses, ignitors, ballasts—or pole knockdowns. Routine mainte­nance is scheduled activities such as group lamp replacement or luminaire cleaning that are intended to produce a certain level of performance of the lighting system and eliminate some of the demand maintenance [18].

7.30.2 Maintenance Guidelines

A comprehensive discussion of roadway lighting maintenance is presented in “Design Guide for Roadway Lighting Maintenance,” IESNA DG-4...

Maintenance must be considered from the earliest design stages of a lighting project. Top-quality materials should be specified and then arranged or located to protect the components from the potential hazards of the environment, whether these be rain, mois­ture, ultraviolet degradation, or threat of vehicular impact. After a system is installed and tested for operation and for component integrity, proper maintenance procedures can produce continued high performance of the roadway lighting system. If the lighting system is not properly maintained, the responsible authorities may expose themselves to potential liability—plus increased costs if expendable items are not replaced as they reach the end of their service life, because they can cause other components to fail.

7.30...

Before any lighting system is accepted as complete, or preferably before the electricity is turned on, several tests should be conducted to ensure the quality of the components:

Insulation tests. The contractor should measure the conductor insulation resistance to ground of each lighting circuit using a 500-V megohm-range type instrument. A record should be made of each phase conductor’s resistance to ground. The circuits should measure a minimum of 250,000 Q resistance to ground before the power is turned on. The test should be arranged to test splices and all components of the circuit. Ground resistance test. Using an instrument designed for the purpose, the con­tractor should measure the resistance of each ground rod...