Standard Test Method for Field Measurement of Raised Retroreflective Pavement Markers Using a Portable Retroreflectometer

Importancia y uso:

5.1 Measurements of R_I made by this test method, with the 0.2° observation angle, are related to visual observation of raised retroreflective pavement markers at distances of approximately 220 m (720 ft) for cars or approximately 440 m (1440 ft) for trucks when illuminated by tungsten filament light sources such as car headlights.

5.2 There are some castings that block vehicle illumination of a portion of the marker mounted within it. In this case, measured R_I can be significantly lower than when the marker is photometered outside the casting, but will correspond to the visual observation.

5.3 The test method is not applicable to raised pavement markers mounted in depressions cut into the pavement.

5.4 The coefficient of luminous intensity of raised retroreflective pavement markers degrades with traffic wear and requires periodic measurement to ensure that sufficient visibility is provided to the driver.

5.5 The quality of the pavement markers as to materials used, age and wear pattern, will have an effect on the coefficient of (retroreflected) luminous intensity. These conditions need to be observed and noted by the user.

Subcomité:

E12.10

Volúmen:

06.01

Número ICS:

93.080.20 (Road construction materials)

Palabras clave:

portable retroreflectometers; raised retroreflective pavement markers; retroreflection;