Edwards Diffstak 63/150 - Fill the Pump with Fluid; Safety of Vapour Pump Fluids

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Installation
B344-21-880 Issue N
3.9 Fill the pump with fluid
3.9.1 Safety of vapour pump fluids
Vapour pump fluids are not dangerous when used in a pump that is operated correctly. But if the pump is operated
incorrectly and is allowed to get to very high temperatures, the pump fluid can go through a process of thermal
breakdown. The breakdown products which result can be dangerous. Table 2 gives more information about the
thermal breakdown of the different vapour pump fluids. Thermal breakdown is more likely to occur if the breakdown
temperature is close to the operating temperature of your pump.
Table 2 - Pump fluid thermal breakdown
Vapour pump fluid
Edwards
Product
Auto-ignition
Temp.
°C
Breakdown
Temp.
°C
Thermal
breakdown
products
Type of
danger
Possible
injury
Silicone fluids
(methyl phenyl
siloxanes)
DC702,
DC704EU,
DC705
≈ 500 400 Decomposed
hydrocarbons
and silicon
based species
Negligible Negligible
Alkyl
naphthalene
fluid
Edwards L9 70 ≈ 300 Naphthalene
and
decomposed
hydrocarbons
Naphthalene
is poisonous
in large
quantities by
ingestion and
skin contact
Minor (first
aid may be
required)
Polyphenyl ether
(5-Ring)
Santovac 5 590 ≈ 460
(in helium)
Phenol,
benzene &
phenolic
materials
Phenolic
materials are
poisonous &
caustic by
ingestion and
skin contact
Major (a lost
time accident
can occur)
Paraffinic fluids &
ester fluids
Apiezon
A, B, C,
AP201
and AP301
≥ 305 < 300
(in air)
Decomposed
hydrocarbons
Fire (Note:
AP201 has a
low
auto-ignition
temperature)
Major (a lost
time accident
can occur)
Perfluoro-
polyether
None None > 260 Decomposed
fluorocarbons
including
hydrofluoric
acid
Highly
aggressive
materials.
Poisonous and
caustic by
inhalation
and skin
contact.
Potentially
fatal