59
Gaseous
Corrosivity
Level
Copper Reactivity
Level
Silver Reactivity
Level
Description
controlled such that
corrosion is not a
factor in determining
equipment reliability.
G2 (moderate)
< 1000 Å/month
< 1000 Å/month
An environment in
which the effects of
corrosion are
measurable and may
be a factor in
determining
equipment reliability.
G3 (harsh)
< 2000 Å/month
< 2000 Å/month
An environment in
which there is high
probability that a
corrosive attack will
occur.
GX (severe)
≥ 2000 Å/month
≥ 2000 Å/month
An environment in
which only specially
designed and
packaged equipment
would be expected to
survive.
See the table below for the requirements on the copper and silver corrosion rates.
Table 8-8 Concentration Limitation on Corrosive Airborne Contaminants in a Data
Center
Group
Corrosive Gas
Unit
Concentration
Group A
H
2
S
ppb
a
< 3
SO
2
ppb
< 10
Cl
2
ppb
< 1
NO
2
ppb
< 50
Group B
HF
ppb
< 1
