Wavy baseline

HI all, I encountered an issue where my blank injection baseline shows a wavy trend from 0min - 12 minutes. i have changed my fuel gas as initially, I'm suspecting that my fuel gas purity does not reach 99%.

hope to get an answer soon.

Thank you.

  • I'm guessing this is FID since you mention fuel gas - is that correct?  Fuel gas impurities can cause some of this.  Make sure the gases you are using are 99.9995% purity or higher.  Filters and traps on the gas supply lines may help - are any currently installed?  I'd also check the data collection rate on the detector.  Sometimes too high of a rate can cause excess noise.  For most GC analyses, 10-20 Hz will work fine.

Was this helpful?