Measures of amount of wear sustained by snowplowable raised reflective pavement markers are recommended to encourage the use of objective measures and provide a basis for standardization of wear measures. Such an evaluation was carried out on nj-29 and nj-31 in 1984-1985 and on us-1 in 1974-1975 after two successive winters of use. The effect and extent of various types of physical wear were checked. The scope of this effort allowed determination of which measures were useful in classifying average functional reflective surface area and average visibility distance from year to year, marker to marker, and route to route, so that a statistical analysis of differentiation between the items of comparison could be performed at a high levelof significance. There is an increasing need to establish a scientific relationship between the day and night measures, which could be generated by future research work. This paper appeared in transportation research record no. 1148, hazardous materials transportation, work-zone traffic control, and traffic marking materials. for covering abstract see irrd no 818401.
Abstract