The comments on this method is about the density. It is not clear to us why the use of 31.5 lbs/ft3 even after referencing the footnote B on the method. A true particle count should take into account the exact bulk density of the specific sample that is being measured, since one reports the number of particles per unit of mass. Granular products can vary in density from DE (20 lbs/ft3) to sand (90lbs/ft3). For clay the density that can better be represented by 33.5 lbs/ft3. Upon review of the method it was felt the method should be discussed and possibly changed prior to re-approval.