Test Certificate No. 0913-2015-02 regarding the suitability of the RetroTek-M Mobile Pavement Retroreflectometer for measuring the coefficient of retroreflected luminance RL of the surfaces of road markings.

Direct quotes from the StrausZert Test Certificate:

Accuracy compared with Hand-Held Retroreflectometers:

“The test confirms that the measuring system RetroTek-M provides, within the scope of an acceptable measuring accuracy, the same measured values of the coefficient of retroreflected luminance RL as a portable, handheld measuring device”.

Repeatability at various speeds:

“The coefficient of retroreflected luminance RL can be detected with a good measuring accuracy by the measuring system RetroTek-M, independent of the measuring velocity”.

Test Conclusion:

“The RetroTek-M Mobile Pavement Retroreflectometer is hereby deemed to be well suitable for measuring the coefficient of retroreflected luminance RL of road markings according to the measuring geometry and measuring conditions given in the European Standard EN 1436.”

EN 1436: StrAus-Zert Test Certification (English)
EN 1436: StrAus-Zert Test Certification (Deutsch)

Test Certificate No. 0913-2017-04 regarding the suitability of the RetroTek-MU Mobile Pavement Retroreflectometer for measuring the coefficient of retroreflected luminance RL of the surfaces of road markings.

Direct quotes from the StrausZert Test Certificate:

Accuracy compared with Hand-Held Retroreflectometers:

“The tests confirm that the measuring system RetroTek-MU provides, within the scope of an acceptable measuring accuracy, the same measured values of the coefficient of retroreflected luminance RL as a portable, handheld measuring device. The accuracy of the measuring results is not influenced by the colour (white or yellow) of road markings.”

Repeatability at various speeds:

“The coefficient of retroreflected luminance RL can be detected with a good measuring accuracy by the measuring system RetroTek-MU, independent of the measuring velocity.”

Test Conclusion:

“The deviations of the measurement results are low overall, especially considering that the difficult measuring conditions (different measuring areas, uneven marking surface, non-homogenous structure of the marking surface, non-homogenous bead distribution) cause inaccuracies that are not attributable to device inaccuracy.”

“The RetroTek-MU Mobile Pavement Retroreflectometer is hereby deemed to be well suitable for the dynamic measurement of the coefficient of retroreflected luminance RL of road markings according to the measuring geometry and measuring conditions given in the US-Standard ASTM E 1710 resp. in the European Standard EN 1436 and delivers the same results as a portable retroreflectometer. The measuring results are independent of the measuring speed and are not influenced by the kind, form and colour of the road markings.”

ASTM E1710: STRAUS-ZERT TEST CERTIFICATION

RetroTek-MU Mobile Pavement Marking Retroreflectometer Evaluation by Texas A&M Transportation Institute. Report Prepared for Reflective Measurement Systems by Adam Pike, P.E. Associate Research Engineer, January 2019

Summary of Findings from the TTI Evaluation:

This testing was designed to evaluate the accuracy of the RetroTek-MU mobile pavement marking retroreflectometer across a range of factors. These factors are typically encountered during data collection and their impact needs to be minimized to have a system that can continually collect accurate retroreflectivity data across a range of pavement markings in various conditions. The testing included 42 tests on 91 pavement marking segments over a variety of road segments to evaluate the mobile retroreflectometers performance.

The open road testing evaluated typical road surfaces and pavement markings in typical data collection conditions.

Overall the retroreflectivity trend along the test sections was consistent between the RetroTek-MU and the portable retroreflectometer with an R2 value of 0.9417. The average systematic error was −5.7 percent with an average random error of 8.7 percent. The results indicate that when considering marking color or marking pattern the error was approximately 11 percent or less. The measurements at the left or right in-lane positions differed by approximately 10 percent or less when compared to the center of the lane position. The low RL calibration level resulted in data that were between 6 and 9 percent lower on average than data collected with the high RL calibration setting.

The closed course testing results indicated that the majority of the mobile data were within 10 percent of the portable data. The average systematic error was 0.9 percent, with an average random error of 5.7 percent. Overall the retroreflectivity trend along the test sections was consistent between the RetroTek-MU, and the portable retroreflectometer with an R2 value of 0.9878. The mobile and portable data closely matched each other with almost no bias as the line of equality and data trend line were nearly on top of each other. The average error was less than 7 percent for any subset of color or marking pattern. The difference between the measurements with and without the RRPMS was less than 3 percent different on average.

The testing and results described in this report provide quantitative information as to the accuracy of data collected with the RetroTek-MU mobile pavement marking retroreflectometer across a range of factors.

Download the full Evaluation report HERE