There must be three reference compounds as well as a new reference compound used for testing. The original reference compound standard must be 8 inches long and 1 inch wide. Laboratories cut the material to the standard size specifically for rubber abrasion testing.

The standard reference compound size should measure 1 x 1 x 0.25 inch. The specimen must be of this size in order to fit into the NBS abrasion testing machine’s arm slot.

If a specimen is over the standard thickness, it will require buffing until it is reduced to the appropriate size. On the other hand, thinner specimens should be stacked or piled in layers until the required thickness is achieved.

The new reference compound must have been stored during the past six months prior to the scheduled testing. A compound that has been stored for more than six months is not qualified to be used as specimen for the test.

Also, the reference compound must undergo a curing process before the test. This is necessary to make sure that the material will get an even abrasion. The compound reference is cured at a pre-determined temperature.

There is likewise a breach in the compound used for conditioning the new abrasive paper. This break has similar dimensions to the standard reference compound.