Patent ID: 8152909

Claim:
A gas chromatography system comprising: an electronic flow control module for providing a carrier gas; an injector for receiving a liquid sample; a vaporizer for vaporizing the liquid sample introduced into the injector; a gas delivery line connecting the electronic flow control module and the injector, the gas delivery line allowing flow of carrier gas from the electronic flow control module to the injector; a column connected to the injector, the column comprising a stationary phase, wherein the carrier gas elutes the vaporized sample through the column; a check valve situated in the gas delivery line downstream of the electronic flow control module and upstream of the injector, the check valve sealing in response to a change in pressure in the injector that reverses flow in the gas chromatography system and substantially preventing back flow of liquid sample and vaporized sample into the gas delivery line; and a detector providing a response signal representing output of the column.