Gas sampling apparatus including a sealed chamber cooperative with a separate detector chamber

摘要

An isolated detector for gas is set forth and incorporates a closed source chamber in cooperation with a sample chamber through which sample gas flows. Gas within the source chamber comprises Krypton which is excited to a metastable state by a pulsed, high voltage, direct current spark. Subsequent decay of metastable argon emits ionizing radiation which passes through a membrane window into the sample chamber thereby ionizing selected constituents within the sample gas. Charged particles resulting from the ionization of selected constituents are collected with voltage biased electrodes in the sample chamber, and the magnitude of the resulting current flow is related to the concentration of the ionized molecules or compounds. The apparatus for generating ionizing radiation requires no external source of gas, is rugged, is relatively inexpensive to manufacture and operate, and exhibits an operating life much longer than source lamps used in prior art devices. The preferred embodiment of the invention is directed to the quantitative measure of impurities or pollutants in air samples.