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Tech Tip
Affected by the HeliumShortage?
Switch Your GC Carrier Gas to Hydrogen
By Al Carusone, Technical Service
Visit us on-line at
www.restek.com/outofgasto see the following
technical articles:
“Helium Supply Deflates,
Gas Prices Rise Quickly”
“Parker Hydrogen Generators,
Is Your Lab Wasting Money
on Bottled Gas?”
“Using Hydrogen for
Gas Chromatography”
“Loctite Saves Almost $20,000 per
Year by Generating Its Own
Hydrogen for GC/FIDs”
“Parker Balston® Hydrogen
Generators Fast Facts”
Faced with helium shortages and prices that continue to soar upwards like a
runaway party balloon? Consider switching your carrier gas to hydrogen.
Hydrogen is a safe alternative to helium, and high quality gas is readily avail-
able from either cylinders or hydrogen generators.
Switching to hydrogen is cost-effective and can improve GC performance.
Hydrogen provides shorter (by half if running isothermally) analysis times
than helium and many times yields overall better separations. Also, with split-
less injection, hydrogen’s higher velocities carry the solutes from the inlet to
the column faster and more efficiently, decreasing the potential for band
broadening. However, while hydrogen is a great choice for most GC work, it
is difficult to remove from the MS source and energizing the source without
the pumps running could cause an explosion. Therefore, hydrogen is not typ-
ically recommended for mass spectrometry applications.
The most common concern when considering a switch to hydrogen is the risk
of explosion. Safety depends largely on whether a GC is back pressure regu-
lated or head pressure regulated. Generally older instruments use a pressure
regulator located upstream of the injection port (head pressure regulated). In
the event of a leak the upstream pressure regulator will maintain pressure, but
overall flow can increase dramatically. This situation can lead to an explosion
if hydrogen carrier gas fills the hot GC oven. Check your instrument manual
to make sure your instrument is either back pressure regulated or equipped
with safety features to prevent major leaks. Many instrument companies also
are now recognizing the benefits of using hydrogen as a carrier gas and are
manufacturing their latest models with additional safety features designed to
prevent hydrogen build-up and reduce the risk of explosion.
Hydrogen is available in cylinders, but it can also be produced on-site using a
hydrogen generator. Hydrogen generators are much safer and more cost-
effective than high pressure cylinders. All hydrogen generators offered by
Restek are equipped with built-in sensing circuits that will automatically shut
down the generator in the rare case that a leak is detected. Another advantage
is that hydrogen generators produce hydrogen on-demand, meaning only
small volumes (50-100mL) are stored at any one time. Producing hydrogen
as it is consumed is much safer than using cylinders which each store up to
9,000 liters.
Hydrogen is a safe, dependable alternative to helium, and hydrogen genera-
tors are an ideal way to produce the hydrogen your lab requires. They include
great safety features and are cost-effective; based on cylinder savings alone, a
generator pays for itself in only one or two years. If your lab has been affected
by the current helium shortage and you are considering a switch to hydrogen,
see the titles in the sidebar for more information. You’ll find switching to
hydrogen and using a hydrogen generator to supply your lab offers significant
financial and performance benefits.
Get More!
Information on switching
from helium to hydrogen.
See page 18 & 19 for our listing of Hydrogen Generators.