Hydrocarbon and carbon dioxide contamination causes signal quenching and increased background noise. Impurities can become concentrated on purge and trap sampling devices and injected into the device. Atmospheric, neon, and hydrogen impurities cause baseline noise, signal polarity shifts, reduced sensitivity, and instability. Contaminants in the carrier gas can cause reduced sensitivity, baseline drift, ghost peaks, and absorption of some polar compounds. Hydrocarbon impurities increase baseline noise.
Oxygen reduces sensitivity.
Oxygen impurity causes filament oxidation resulting in reduced sensitivity.