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Appendix C
Soil Vapor (SV) and Fuel Vapor (FV)
Operation
The Soil Vapor Monitor has a combustible sensor only; the Fuel Vapor
Monitor has an oxygen sensor in addition to the combustible sensor. The Soil
and Fuel Vapor Monitors have two operating modes, “CH4” mode and “ME”
mode. When in the “CH4” mode, the Innova functions as a normal
instrument, and the unit will respond to all combustible gases, including
methane. When in the “ME” (Methane Elimination) mode, the voltage to the
combustible sensor is changed, which causes the sensor to respond only to
non-methane combustible gases. This allows the user to discriminate
between methane and non-methane hydrocarbons.
Table C-2 Sensor Specifications
Sensor
Sensor
Type
Detection
Range
Warn
Setting
Alarm
Setting
Accuracy
(of
full-scale
range
)
Repeatability
(of calibration
span value)
Hydrocarbon
Catalytic
0 to 100
% LEL
10
% LEL
50
% LEL
+ 5%*
+ 2%
Hydrocarbon
Catalytic
0 to 1,000
ppm
100
ppm
500
ppm
+
25
%
+ 5%
Specifications apply with 40% hexane calibration.
*The + 5% specification in %LEL applies when in “ME” (methane
elimination) mode. Readings taken in “CH4” mode have + 10% accuracy.
NOTE
The Innova FV and SV instruments provide a 90% measurement value
within 30 seconds. For the most accurate readings, allow the unit to
measure for 2 minutes.
