System Manual Oxford Instruments Plasma Technology OIPT Systems
8.3 Mandatory requirements for Cryogenic pump extraction
WARNING
ANY CRYOGENIC PUMP, WHICH PUMPS HAZARDOUS GASES MUST HAVE, A VENT PIPE
FITTED TO ITS RELIEF VALVE TO PREVENT THE RELEASE OF GAS INTO THE CLEAN
ROOM.
THE PUMPS COLLECT THE PROCESS GASES AND THE GASEOUS RESIDUES DURING
OPERATION. THESE GASES ARE RELEASED THROUGH THE RELIEF VALVE DURING PUMP
REGENERATION OR IF ELECTRICAL POWER IS LOST.
If a cryogenic pump is used to pump toxic, corrosive, or flammable gases, a written
action plan is required. This must be prepared in consultation with OIPT and other
competent bodies. Specialised equipment such as scrubbers and furnaces may be
needed to dispose of hazardous gases.
If the pumped gases contain more than 20% oxygen, a vent pipe must be fitted to the
system’s cryo pump outlet connector. The vent pipe must be routed to a safe place
outside of the clean room and conform to local safety standards.
If a cryogenic pump is used to pump gases containing more than 20% oxygen, the
associated roughing pump(s) must be lubricated with a PFPE fluid, e.g. Fomblin or
Krytox.
Services Specifications
Printed: 6-Jan-10, 8:53 Page 19 of 22 Issue 21: January 10
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