Use of the "I" gas line option
For ASM 180 TD and ASM 180 TD+
4/11
C 70
Edition 03 - May 97
Alcatel Vacuum Technology France - ASM 180 TD/TD+ - ASM 181 TD+ User’s Manual
- the most commonly used carrier gas is
nitrogen
.
- In order to be able to identify leaks of approximately 10
-9
mbar.l/s, the carrier gas must have a helium content which is
less than a few ppb (10
-9
).
- If "0.999 999 999 concentration" nitrogen is considered
too expensive, nitrogen obtained from a tank or a source of
liquid nitrogen can be used.
- Any gas free of helium can be used as a carrier gas (e.g.
l'Argon).
However, for safety reasons, the method is not applicable to
process gases which are toxic, reactive, explosive or flammable.
In addition, the detector is not designed to pump chemically
reactive gases.
Choice of carrier gas
