During a night inspection, dark streaks were observed on the faces of many reflectorized highway signs. Although the streaks were not visible during daylight, they substantially reduced the reflectivity of the signs at night. This study was initiated to determine the source of the streaks and to define remedial measures. An investigation revealed the streaks were caused by a residue of titanium dioxide from the paint on the wooden posts supporting the signs. As the paint deteriorated, the residue was transported down the sign faces by rain, and, subsequently, the titanium dioxide was deposited. The study concluded that clear coating would remove the streaks on existing signs, and it was recommended that in the future signs be installed with spacers, similar to nylon washers, between the sign panels and the painted posts.
Texas counties expressed a desire to the Texas Department of Transportation (TxDOT) to postadvisory signs on the roadside to alert motorists when a bu...
Many of the design practices that Texas Department of Transportation (TxDOT) uses for large andsmall sign mounting were established many years ago. Th...
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United States Department of Transportation
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