WHEN DELENEATORS ARE USED OUT LINE THE REQUIRED VEHICLE PATH THROUGH A HIGHWAY CONSTRUCTION SITE, THE REFLECTIVE UNIT SHOULD BE PLACED A MINIMUM OF_____INCHES ABOVE THE ROADWAY?

WHEN DELENEATORS ARE USED OUT LINE THE REQUIRED VEHICLE PATH THROUGH A HIGHWAY CONSTRUCTION SITE, THE REFLECTIVE UNIT SHOULD BE PLACED A MINIMUM OF_____INCHES ABOVE THE ROADWAY?