Agilent Technologies 5975T LTM GC Operation Manual page 21

Dangers unique to GC/MSD operation
Hydrogen presents a number of dangers. Some are general, others are unique
to GC or GC/MSD operation. Dangers include, but are not limited to:
• Combustion of leaking hydrogen.
• Combustion due to rapid expansion of hydrogen from a high-pressure
• Accumulation of hydrogen in the guard column enclosure and subsequent
• Accumulation of hydrogen in the MSD and subsequent combustion.
Hydrogen accumulation in a GC/MSD
The GC/MSD cannot detect leaks in inlet and/or detector gas streams. For this
WA R N I N G
reason, it is vital that column fittings should always be either connected to a column
or have a cap or plug installed.
All users should be aware of the mechanisms by which hydrogen can
accumulate
suspect that hydrogen has accumulated. Note that these mechanisms apply to
all mass spectrometers, including the GC/MSD.
Table 3
Mechanism
Mass spectrometer turned off
5975T LTM GC/MSD Operation Manual
cylinder.
combustion.
(Table 3) and know what precautions to take if they know or
Hydrogen accumulation mechanisms
Results
A mass spectrometer can be shut down
deliberately. It can also be shut down accidentally
by an internal or external failure. In an external
failure, the mass spectrometer shutdown does not
shut off the flow of carrier gas. As a result,
hydrogen may slowly accumulate in the mass
spectrometer. However, in an external power
failure, the EPC will be turned off and the flow of
gas stopped.
1
Introduction
21