The article describes a method using gas chromatography to detect very small amounts of gases like carbon monoxide, hydrogen, and methane in air samples. By using helium as a carrier gas and purifying it carefully, the researchers were able to achieve extreme sensitivity in detecting these gases. They made slight changes to the detector setup and paid close attention to how the analytical column was operated. The results showed that the method could detect gases present in concentrations as low as 2.5 parts per million in a 2.0-milliliter air sample. With further improvements in helium purification and instrument operation, even greater sensitivities could be achieved.