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

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 test method was developed from the “TAPPI Dirt Estimation Chart” to provide a means for size estimation of particulates.

This test method was developed for use with the Transparent Size Estimation Chart and Calibrated Size Estimation Chart sold separately.  

Contact press@tappi.org with questions regarding TAPPI Charts.

There are no refunds for 
the purchase of this digital download.

This is a pdf download of the test method. The actual chart(s) are purchased separately. 

Method for transparent chart for estimation of defect size
Test Method for a transparent chart for the estimation of defect size.

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