System for sampling and analysing gas

摘要

The system (1) has a pump (5) admitting a gas at a pressure that is less than an inlet pressure of a gas analyzer (4) e.g. ionic mobility spectrometer. An enclosure (3) contains an inner atmosphere at a pressure less than atmospheric pressure. A conductance controller (7) e.g. pressure controller, is placed at a delivery side of the pump and produces a gaseous flow of constant value and of same order of amplitude as that of a pumping speed of a sampling pump of the analyzer. A relief valve (6) permits to impose another pressure that is greater than the inlet pressure of the analyzer. An independent claim is also included for a method for sampling a gas sample in an enclosure by using a gas sampling and analyzing system.