A section of winding road frequently enshrouded in fog near oakland, california, was delineated with marker lights. Several features of the lighting units received special attention in addition to the photometric considerations: (1) the design was to be tamperproof, (2) the units were to present a minimum cross-section above the mounting surface so that pedestrians would not trip or slip on the structures, (3) maintenance should be simple and not often required, and (4) costs should be kept to a minimum. The units are mounted on the top of the concrete curb along each side of the two-lane section. The spacing is uniform at 30 ft between units, except at the intersections where gaps are left in the lineal patterns. The design and electrical service are discussed.
Samenvatting