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Breakaway luminaire poles are designed to yield at their base attachment to the foun­dation. There are numerous types of bases currently in service. Some of these are designed for breakaway operation and others are not designed to yield. The nonyielding types have application where vehicle speeds are low and the danger from a falling pole […]

The foundation for a luminaire pole must provide sufficient resistance to overturning moments caused by the static load of the mast arm plus a wind and/or an ice load. It must be capable of maintaining the correct alignment of the luminaire and able to withstand the impact should the pole be struck. For breakaway poles, […]

One problem that has recently been identified is the potential deadly threat posed by the electric circuits after pole impact by an errant vehicle. There are many documented deaths of motorists who survived the impact with a luminaire pole only to be subsequently killed from the resulting explosion and fire. The explosion and fire are […]

Poles are available in a number of materials. The advantages and disadvantages of each follow. Steel. Steel poles are available in galvanized, painted, powder-coated, and weathering types, plus a combination of powder coating over galvanizing. Galvanized is the most popular of the steel types because of the comparatively low cost and extended life. Painted poles […]

The location of a lighting pole is partially dictated by the lighting scheme selected by the designer for a section of roadway. Using the conventional (cobra head) type luminaires requires the pole to be close to the travelway and therefore, unless it is behind a barrier, most likely to be struck by an errant vehicle. […]

The primary purpose of roadway illumination is to increase safety by enhancing night­time visibility. The net safety benefit from increased visibility is influenced by the hazard posed by the roadway lighting or luminaire support acting as a fixed object. If roadway illumination is not warranted, or if it is installed wrong, there is a strong […]

The value of high mast lighting has been highly controversial since its introduction in the early 1960s. Proponents suggested that high mast lighting offered considerable enhancements to visibility. Opponents, on the other hand, argued that high mast lighting was expensive to build, offered little improvement to visibility, and often resulted in light trespass and light […]

Conventional roadway lighting has been the cobra head luminaire mounted on a support arm and positioned at the edge of the roadway or, in some cases, out over the roadway. The base of the pole when a breakaway device is present should be a minimum of 15 ft (4570 mm) from the travelway, but 20 […]

An analytical approach to determining if roadway lighting is warranted was developed through the National Cooperative Highway Research Program (NCHRP Report 152) using four comprehensive evaluation forms. The four forms relate to non-controlled — access roadways, intersections, freeways, and interchanges, and are presented in Figs. 7.61, 7.62, 7.63, and 7.64, respectively [10]. The forms are […]

The use of artificial daytime lighting is warranted when user visibility requirements are not satisfied by the natural sunlight. Overall tunnel visibility varies considerably with such factors as geometry of the tunnel and its approaches, traffic characteristics, roadway and environmental reflective surfaces, the climate and orientation of the tunnel, and visibility objectives. Comprehensive literature is […]