A baseline suddenly rockets off-scale or drops below zero during a temperature-programmed run. Extraneous peaks appear out of the blue in the chromatogram. The integration of a critical peak becomes unreliable because of a hump that shows up right under the peak instead of anywhere else in the chromatogram. Peak resolution quickly deteriorates and stationary phase bleed unexpectedly rises.
When baseline problems arise, you shut down your instrument and start troubleshooting. Of the three parts of the GC that could be causing the problem—the instrument itself, the sample, and the gas supply—where do you focus first? Probably on the gas supply. You change out the in-line and on-board purifiers; you order replacement gas cylinders; you wonder if the regulators and all of the gas delivery system now have to be checked and possibly replaced. And you wait for parts to be shipped, service engineers to appear, and your gas supplier to check out the culprit cylinder. The consistent, ultra-high-purity of carrier gases supplied in BIP cylinders allows you to categorically eliminate the carrier gas as a source of contamination when troubleshooting, allowing you to focus on finding the true source of your baseline problems.
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