PerkinElmer PINAACLE 900 Series, Customer Hardware And Service Manual

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62
Preparing Your Laboratory
Argon:
Argon is required for external and internal gas streams through the THGA or HGA
graphite furnace or as a carrier gas with mercury/hydride systems such as the FIAS
or FIMS flow injections systems or the MHS-15. The quality criteria listed in the
following table for argon are suitable for these applications. Normally, for graphite
furnace operation, gaseous argon is used, although either liquid or gaseous argon
can be used. The choice of liquid argon or gaseous argon tanks is determined
primarily by the availability of each and the usage rate. Liquid argon is usually less
expensive per unit volume to purchase, but cannot be stored for extended periods.
If liquid argon is used, the tank should be fitted with an over-pressure regulator
which will vent the tank as necessary in order to keep the liquid argon cool enough
to remain in the liquid state. Gaseous argon tanks do not require venting and
consequently can be stored for extended periods without loss.
A dual-stage cylinder regulator that can be used with either gaseous argon or
nitrogen is available from PerkinElmer (Part No. 03030284). The regulator has a
CGA 580 fitting, and includes a color-coded hose with 1/4-inch Swagelok®
fittings to permit direct connection to the regulator and to the instrument gas
controls.
Table 2-5. Specifications for the Flame Gases