Perm tube tech: Rigorous discussion of “K” value and best way to calculate gas concentration

Time to get seriously techie on perm tube calibration fundamentals… This is a detailed analysis of the so-called “K” constant used with permeation devices, to enable the calculation of the emitted gas concentration.  Over the years, many of our customers—and Interscan’s own technical personnel—have been frustrated by the confusing and inconsistent documentation on this matter…