Transparent chart for the estimation of defect Test Method T 564 sp-21

There are many applications where it is desired to measure the size of spots, defects or inclusions in paper and other industrial materials such as textiles or plastics. This chart was developed from the “TAPPI Dirt Estimation Chart” to provide a means for size estimation.

This test was developed for use with a transparent version of the Dirt Chart. 
Transparent Size Estimation Chart  and Calibrated Size Estimation Chart sold separately.  
Contact with questions regarding TAPPI Charts.


Transparent chart for the estimation of defect size
Transparent chart for the estimation of defect size Test Method T 564 sp-21

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