Patent ID: 8424367

Claim:
A system for determining the rate of gas permeation through a film comprising: a continuous flow permeation cell, a mass spectrometer, a computer configured to receive data from the mass spectrometer, a test gas source, and a carrier gas source, the continuous flow permeation cell comprising a supply chamber in communication with the test gas source and a receiving chamber in communication with the carrier gas source and the mass spectrometer, wherein the supply chamber is configured to be separated from the receiving chamber by a test film such that when a test gas stream is fed to the supply chamber from the test gas source and a carrier gas stream is fed to the receiving chamber from the carrier gas source, at least a portion of the test gas stream permeates from the supply chamber through the test film to the receiving chamber and mixes with the carrier gas stream and the mixture flows to a gas inlet channel of a variable leak valve such that the mixture discharges at an end of the gas inlet channel immediately adjacent to the variable leak valve to reduce dead volume and passes through the variable leak valve to the mass spectrometer, the variable leak valve configured to permit only a small volume of the mixture to be sampled by the mass spectrometer and limit time delay associated therewith, data received from the mass spectrometer being utilized by the computer to determine the rate of permeation of the test gas stream through the film.