Connect The Nitrogen Supply; Flammable/Pyrophoric Materials - Edwards iXH100 Instruction Manual

M561-00-880 Issue C
3.5

Connect the nitrogen supply

Ensure that your nitrogen supply conforms to the requirements given in the Technical Data Section. If it doesn't,
the gas pipelines may become blocked or the system may be damaged.
Refer to Figure 4, item 14 for location of the nitrogen purge port. The gas module inside the system may be adjusted
to suit process demands. Refer to
the facility for a nitrogen purge.
Note: Refer to Section 2.4
3.5.1

Flammable/pyrophoric materials

You must obey the instructions and take note of any precautions given below to ensure that
pumped gases do not enter their flammable ranges.
When flammable or pyrophoric materials are present within the pump there may be additional risks that the user is
responsible for assessing and managing as part of the entire Process Tool installation. The severity of the risks and
the necessary control measures will depend largely on whether the tool exhaust is in the flammable region, if this is
part of normal Process Tool operation, or if it might only occur under rare conditions. The additional risks arise
because all dry pumps must be considered a potential source of ignition owing to the heat of compression, or possibly
friction. If ignition occurs then the following may happen:
High pressures could occur within the pump and may not be contained

A flame front could travel back up the foreline

A flame front could travel downstream from the exhaust of the pump.

Industry best practice suggests that the following measures will reduce the risks of pumping flammable mixtures and
pyrophoric materials, but it is the user's responsibility to carry out a risk assessment and take appropriate measures:
Do not allow air to enter the equipment

Ensure that the system is leak tight

Ensure that gases in the pump do not enter the flammable range. This may be achieved by diluting gases in

the pump by supplying sufficient inert gas purge. For example, dilution with nitrogen to below one quarter
LEL (lower explosive limit) or, if that is not practical, to below 60% LOC (limiting oxidant concentration).
The gas module supplied with the pump is not intended to perform a safety function. Users may need to

consider adding appropriate measures to monitor the flow of purge gas, for example external sensors.
Systems that are fitted with the loadlock gas module must not be used on applications pumping flammable or
pyrophoric materials.
For further information please refer to Semiconductor Pumping Application Guide (Publication no. P411-00-090) or
contact Edwards.
Page 28
CAUTION
Section 5.6 for instructions on gas module configuration. The pXH does not have
for nitrogen supply requirements.
WARNING
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