This test method covers measurement of the retroreflective properties of dry, horizontal pavement marking materials, using a Mobile (vehicle-mounted) Retroreflectivity Unit (MRU) operated at posted roadway speeds at a prescribed geometry. The prescribed geometry corresponds to the European Committee for Standardization (CEN) geometry and is the standard geometry adopted by ASTM E1710. This test method ensures that night-time visibility provided by pavement markings is adequate. This applies to the measurement of the pavement marking retroreflectivity using mobile instruments. This standard was formerly designated as provisional method of test TP 111.