12
7890 Series GC Site Preparation Checklist
Issued: 09-Dec-2015, Revision: 1.8
Copyright
2013
Agilent Technologies
Page 12 of 15
Considerations for Hydrogen Carrier Gas
If planning to use hydrogen carrier gas, note that special considerations apply due to hydrogen’s
flammability and chromatographic properties. Refer to the to the "Gas Supplies/Requirements for
Hydrogen as a Carrier Gas" section in the "Agilent GC, GC/MS and ALS Site Preparation Guide" for more
detail.
Hydrogen Safety
When using hydrogen as the carrier gas or fuel gas, be aware that hydrogen gas can flow into the GC
oven and create an explosion hazard. Therefore, be sure that the Hydrogen gas supply is turned off until
all connections are made and ensure the inlet and detector column fittings are either connected to a
column or capped at all times when hydrogen gas is supplied to the instrument.
In any application using hydrogen, leak test all connections, lines, and valves before operating the
instrument.
Agilent highly recommends the G3388B Leak Detector or equivalent to safely check for leaks.
Supply tubing for Hydrogen Gas
Agilent recommends using NEW, chromatographic quality copper or stainless steel tubing and fittings
when using hydrogen.
Do not re-use old tubing when installing or switching to hydrogen carrier gas. Hydrogen gas tends to
remove contaminants left on old tubing by previous gases (by helium, for example).
These contaminants can appear in detector output as high background noise or hydrocarbon
contamination for several weeks.
Do not use old copper tubing with hydrogen gas. Old copper tubing can become brittle and create a
safety hazard.
Hydrogen Gas Supplies
Hydrogen can be supplied from a gas generator or from a cylinder.
Agilent recommends use of a high-quality hydrogen gas generator. A high-quality generator can
consistently produce purity > 99.9999%, and the generator can include built-in safety features such as
limited flow rates, and auto-shutdown.
If using a hydrogen gas cylinder, Agilent recommends use of Gas Clean Filters to purify the gas.
Consider additional safety equipment as recommended by your company safety personnel.
