1.1 This test method covers the procedure for measuring surface frictional properties as a function of speed using the dynamic friction tester (DF tester).

1.2 The DF tester consists of a horizontal spinning disk fitted with three spring-loaded rubber sliders which contact the surface as the disk rotational speed decreases due to the friction generated between the sliders and the surface. A water supply unit delivers water to the surface being tested. The torque generated by the slider forces measured during the spin-down is then used to calculate the friction as a function of speed.

1.3 The DF tester can be used for laboratory investigations and in the field on in-situ surfaces.

1.4 The values stated in SI (metric) units are to be regarded as standard. The inch-pound equivalents are rationalized, rather than exact mathematical conversions.

1.5 The Nippo Sangyo dynamic friction tester is covered by a patent. Interested parties are invited to submit information regarding the identification of an alternative(s) to this patented item to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of the responsible technical committee,1 which you may attend.

1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.

1.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.