This procedure describes a method for generating, preparing and analyzing samples of new and unused brake friction materials for their chemical constituents.
The states of Washington and California passed laws in 2011 restricting the amount of cadmium, copper, hexavalent chromium, lead and mercury their compounds in brake friction materials. As part of the legislation, brake friction materials are required to be analyzed to confirm the levels of the restricted elements are below the values stated in the legislation. The SAE J2975 provides a method on how to generate samples of brake friction material for analysis, how to prepare the samples for analysis and how to analyze the samples.
This revision expands the applicability of EPA method 3051A and EPA method 6010C (used in tandem) for mercury detection and measurement. These two methods combined eliminate the possible interference from copper and sulfides, which are common in friction materials. The revision also allows EPA method 6020A to be used for detection restricted substances.