Agilent Technologies 5975T LTM GC/MSD, Troubleshooting And Maintenance Manual

Page: 19 / 270

Introduction
1
Troubleshooting and Maintenance Guide 19
Hydrogen Safety
Hydrogen is a commonly used GC carrier gas. Hydrogen is
potentially explosive and has other dangerous characteristics.
• Hydrogen is combustible over a wide range of
concentrations. At atmospheric pressure, hydrogen is
combustible at concentrations from 4% to 74.2% by volume.
• Hydrogen has the highest burning velocity of any gas.
• Hydrogen has a very low ignition energy.
• Hydrogen that is allowed to expand rapidly from high
pressure can self-ignite.
• Hydrogen burns with a nonluminous flame which can be
invisible under bright light.
WA R N I N G
The use of hydrogen as a carrier gas is potentially dangerous.
WA R N I N G
When using hydrogen (H
2
) as the carrier gas or fuel gas, be aware
that hydrogen gas can flow into the guard column heated zone and
create an explosion hazard. Therefore, be sure that the supply is
turned off until all connections are made and ensure that the inlet,
MSD, and column fittings are either connected to a column or
capped at all times when hydrogen gas is supplied to the
instrument.
Hydrogen is flammable. Leaks, when confined in an enclosed
space, may create a fire or explosion hazard. In any application
using hydrogen, leak test all connections, lines, and valves before
operating the instrument. Always turn off the hydrogen supply at
its source before working on the instrument.