Apeks Regulator Owner's Manual page 7

Passing hydrocarbons through a valve and regulator creates a
cumulative effect where the hydrocarbons build up over time along the
internal passageways of the equipment. When these hydrocarbons
come in contact with high-pressure oxygen enriched air, they can pose
a very real hazard that can lead to combustion.
Therefore, if a regulator has had use with Grade E breathing air, it
should be returned to an authorized Apeks dealer for overhaul service
including hydrocarbon cleaning, prior to being put back into nitrox
service.
Although second stage components are not exposed to high pressure
EAN, Apeks recommends that the same cleaning procedures be
followed for the complete regulator. This prevents the possibility of
cross contamination and guarantees the cleanliness of the entire
regulator.
NOTE: Apeks offers additional models of regulators that are
designed and manufactured for use with enriched air nitrox where
the percentage of oxygen exceeds 40%. For information about
these models, consult your authorized Apeks dealer.
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