Testex Replica Tape
E122—-B Coarse (0.8 – 2 mils)
E122—-C Extra Coarse (1.5 – 4.5 mils)
E122—-F X-Coarse Plus (4.6 – 5.8 mils)
Elcometer Testex Tape: ASTM D4417 Method B
In summary, ASTM D 4417 Method C and NACE RP0287-95 require the appropriate tape to be rubbed onto the surface.
The thickness of the tape, when the thickness of the backing has been subtracted, gives the peak-to-valley height of the surface.
Measurements should be made at an agreed series of locations, which characterise the surface.