The operation of a mobile retroreflectometer is significantly more complicated than the operation of a portable retroreflectometer. There are many different factors — such as mechanical equipment, operator, and software — that can affect the accuracy of mobile retroreflectivity measurements. Furthermore, it can be challenging to assess the accuracy of mobile measurements. To increase confidence in the accuracy of mobile measurements, TxDOT established a Mobile Retroreflectometer Certification Program.
The basic concept of the certification program is to provide a quantitative basis for evaluating the ability of a contractor to accurately measure the retroreflectivity of long-line pavement markings. A contractor that wishes to be certified would send the personnel and equipment to the TTI mobile retroreflectometer certification course. The course consists of numerous pavement markings of various colors, patterns, and retroreflectivity levels.