Exhaust Venting; Hot Air; Other Gases - Agilent Technologies ALS Handbuch

7820 MSD Site Preparation

Exhaust Venting

During normal operation, the GC exhausts hot oven air. Depending on the
installed inlet and detector types, the GC can also exhaust (or vent)
uncombusted carrier gas and sample. Proper venting of these exhausts is
required for operation and safety.

Hot air

Hot air (up to 425 °C) from the oven exits through a vent in the rear. Allow at
least 25 cm (10 in) clearance behind the instrument to dissipate this air.
Do not place temperature-sensitive items (for example, gas cylinders, chemicals,
WA R N I N G
regulators, and plastic tubing) in the path of the heated exhaust. These items will be
damaged and plastic tubing will melt. Be careful when working behind the
instrument during cool-down cycles to avoid burns from the hot exhaust.

Other gases

During normal operation of the GC with many detector and inlet types, some
of the carrier gas and sample vents outside the instrument through the split
vent, septum purge vent, and detector exhaust. If any sample components are
toxic or noxious, or if hydrogen is used as the carrier gas or detector fuel gas,
these exhausts must be vented to a fume hood. Place the GC in the hood or
attach a large diameter venting tube to the outlet for proper ventilation.
To further prevent contamination from noxious gases, attach a chemical trap
to the vent(s).
If using a μECD, always plan to connect the μECD exhaust vent to a fume hood
or vent it to the outside. See the latest revision of 10 CFR Part 20 (including
Appendix B), or the applicable state regulation. For other countries, consult
with the appropriate agency for equivalent requirements. Agilent recommends
a vent line internal diameter of 6 mm (1/4-inch) or greater. With a line of this
diameter, the length is not critical.
116 GC, GC/MS, and ALS Site Preparation Guide