ASTM D7127-13 PDF

1.1 This test method describes a shop or field procedure for determination of roughness characteristics of surfaces prepared for painting by abrasive blasting. The procedure uses a portable skidded or non-skidded stylus profile tracing instrument. The measured characteristics are: Rt and Rpc. Additional measures of profile height (Rmax and/or Rz) may also be obtained as agreed upon by purchaser and seller. (The digitally-determined profile parameters Rt, Rmax, Ry and Rzlmax are extremely similar in definition.)

1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.

1.3 In general, this method should be limited to the measurement of surface roughness where Rt is in the range 10 to 150 μm (0.4 to 6 mil) and where the Peak Count, Rpc is less than 180 peaks/cm (450 peaks/in.).

1.4 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 and health practices and determine the applicability of regulatory limitations prior to use.