paper porosity measurement density meter

The 41xx series is manufactured by Gurley Precision Instruments, and is a densometer that has the accepted standard for measuring the porosity air-permeability or air-resistance of sheet-like materials such as papers, woven, plastics and membranes. It measures the time required for a given volume of air to flow through a standard area of material being tested under light uniform pressure.

There is a clamping plates with a circular orifice area of 1.0 for the standard and 0.25 or 0.1 square inch for the optional. It can be evaluated on both a direct or indirect basis dependent upon the material and test purpose.