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 provided by the permeation device manufacturers.
We are pleased to present a scrupulously detailed discussion of “K,” that includes a revised formula for the calculation of the emitted concentration. This formula will work for all known brands of permeation devices.
Owing to the complexity of some of the equations included in this write-up, and the limitations of HTML to accommodate such expressions, we present the article as a pdf. If desired, you can jump ahead to page 5 of the pdf to obtain the recommended concentration formula (Equation 1-s)