Where do I find the certificate of analysis

The only certification available for all of our ProWeigh Filter products is the balance certification. This is available at the following link - http://www.envexp.com/download/techsupport/Certificates%20of%20Analysis/Balance%20Certification%20for%20Proweighs/Current%20Year/Balance%20Certification%202014.pdf

is the direction of flow of solution important, if so from coarse side to smooth or smooth to coarse?

If you are following Standard Methods for the determination of various residues, i.e. TSS or TDS, you must have the coarse side up. This does slightly increase the effective filter area and allow for a larger total number of particulates to be collected. The actual pore size is not affected by direction of flow through the filter disc.

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