Field test results of in-place charcoal adsorber leak-testing by pulse mode halide injection

Current recognized practices for adsorber in-place leak tests in the nuclear industry are by the use of intermittent sampling gas chromatographs, or by continuous sampling and continuous read-out halide detectors. Both test methods normally utilize the continuous halide injection technique when testing to ANSI/ASME-N510, Testing of Nuclear Air-Cleaning Systems. The use of continuous reading halide detectors and pulse mode halide injection has made in-place leak testing of charcoal adsorber banks possible, where short halide delay times caused by high humidity and/or high airflow and where the release of contaminants from the adsorber surface interfere with data interpretation and subsequent test results. Interpretations of response curves from actual field measurements are given as examples, where leak test data acquired by previously described methods could not give a definite interpretation. The pulse mode halide injection method with continuous reading halide detection also provides additional information about available adsorbent surface sites and utilizes significantly less fluorocarbon, an already suggested practice