VOLUMETRIC CALIBRATION OF PERMEATION TUBES

Alternative means were needed for calibration of permeation tubes used to generate accurately known low concentrations of gases for use as standards. A microgasometer technique was developed employing a compensated Warburg syringe manometer with a sensitivity of 0.1 μl. The average 95% confidence interval was ± 1 % for rate measurements made over 1- to 2-hour periods on sulfur dioxide permeation tubes; agreement with gravimetric calibrations was good. The theoretical relationships are given for rate calculations with allowances for temperature, pressure, solubility, and compressibility corrections. The methodis a simple, rapid, inexpensive, and broadly applicable fundamental technique. © 1969, American Chemical Society. All rights reserved.