3M™ PROTÉGÉ SG
PORTABLE, REUSABLE, SINGLE-GAS MONITOR
GAS INTERFERENCES
087-0065, Rev D/February 2019
B-1
APPENDIX B. GAS INTERFERENCES
There are known gas interferences to a limited number of chemical compounds. 3M attempts to
identify possible gas interferences to which gas sensors may be exposed; however, not all chemical
compounds that presently exist have been tested.
gas interferences.
• Zero – Indicates tested and confirmed no interferences
• Blank – Indicates not tested
• Neg – Indicates gas produces a negative signal
• Two values in a cell – Indicates initial peak and finish offset (unstable or transition gas) and should
not be used for cross calibration
Table B-1: Gas Interferences
NOTE:
does not show, nor should it be implied, that no addi-
tional interferences may occur. These selectivity ratios are used as guides only. They
are not to be used as calibration factors. The gas species’ actual cross-sensitivities
may vary from the values shown.
Interference Gas:
Sensor Types (all values in ppm)
CO (S
ing
le)
CO (H
2
-R
esista
nt)
H
2
S (S
ing
le)
NH
3
(A
mm
onia)
Cl
2
(C
hlorin
e)
ClO
2
(C
lorin
e D
ioxid
e)
HC
N (H
ydrog
en C
yanide
)
NO (O
xide
)
NO
2
(N
itric D
ioxid
e)
O
3
(O
zone)
PH
3
(P
hosphine
)
SO
2
(S
ulfur D
ioxid
e)
Acetylene (C
2
H
2
)
<3
Ammonia (NH
3
)
0
<0.01
1
0
Arsine (AsH
3
)
0.7
Carbon Dioxide (CO
2
)
0
Neg
0
0.005
Carbon Monoxide (CO)
1
1
<0.02 <0.01
0
0
<0.05
0
0
0
<0.003
Chlorine (Cl
2
)
0
<0.001
1
0.6
1
1.2
≤0.4
Chlorine Dioxide (ClO
2
)
1
1.5
Diborane (B
2
H
6
)
0.35
Ethylene (C
2
H
4
)
1
<0.01
<0.3
0.01
<0.9
Germane (GeH
4
)
0.9
Hydrazine (N
2
H
4
)
-1
Hydrogen (H
2
)
0.12
<0.05 <0.001
<
0.002
0
0.001 <0.003
Hydrogen Chloride (HCl)
