KB001391: What Gases are Required for LC/MS? - General LC/MS 

All the Agilent LC/MS models require supply of Nitrogen gas at a minimum of 3 liters/min up to a maximum of 18 Liters / min (MS TOF ). The required purity level is 99.999 % be it from Gas cylinder / Liquid N2 Dewar / Nitrogen generator - Compressor. As for compressor , it has to be OIL free . For much more specific requirement like operating pressure level , venting requirement etc., our site preparation manual provide the detail depending on the model what you have.