17
3 Operation
3.2.3
Inspection above ground
Area of use
– Measuring very low gas concentrations in poorly accessible
gas pipes (underground or laid in floors)
–
Measurement above ground, above the floor or above possi
-
ble leakage points
Symbol
Unit
–
ppm (parts per million)
– % vol.
Measuring range
Gas-sensitive
semiconductor
0.0 to 10,000 ppm
Thermal
conductivity sensor
0.1 to 5 % vol.
Measurement data display
Fig. 7: Inspection above ground
measuring mode
– Digits, e.g. 0.9 % vol. H
2
– Bar graph with quasi-logarith-
mic scale
