GD-70D - 90 -
10-3 Calibrating with the Target Gas
The calibration instructions in this section apply ONLY to the sensors listed in the table below. If your
sensor is not listed in the table below, you will need to follow the instructions outlined in one of the other
calibration sections. The warm up times listed are the minimum times between powering up a GD-70D and
calibrating that GD-70D.
Calibration Gas/Concentration
Warm Up Time
After Power-Up
C3H8 (Propane) 0 - 100 %LEL Propane: 50% LEL 2 hours
C4H10 (Isobutane) 0 - 100 %LEL Isobutane: 50% LEL 2 hours
C6H14 (Hexane) 0 - 100 %LEL Hexane: 50% LEL 2 hours
CH4 (Methane) 0 - 100 %LEL Methane: 50% LEL 2 hours
Cl2 (Chlorine) 0 - 3.00 ppm Chlorine: 2 ppm 3 hours
CO (Carbon monoxide) 0 - 75.0 ppm Carbon monoxide: 50 ppm 3 hours
0 - 150 ppm Carbon monoxide: 100 ppm 3 hours
0 - 300 ppm Carbon monoxide: 200 ppm 3 hours
H2 (Hydrogen)
0 - 100 %LEL Hydrogen (H2): 50% LEL 2 hours
H2S (Hydrogen sulfide) 0 - 1.00 ppm Hydrogen sulfide (H2S): 1 ppm 3 hours
0 - 30.0 ppm Hydrogen sulfide (H2S): 15 ppm 3 hours
HCN (Hydrogen cyanide) 0.9 - 15.0 ppm Hydrogen cyanide (HCN): 10 ppm 3 hours
N2O (Nitrous oxide) 0 - 500 ppm Nitrous oxide (NO): 250 ppm 1 hour
NH3 (Ammonia) 0 - 75.0 ppm Ammonia (NH3): 50 ppm 3 hours
NO (Nitric oxide) 0 - 100 ppm Nitric oxide (NO): 25 ppm 3 hours
NO2 (Nitrogen dioxide) 0 - 9.00 ppm Nitrogen dioxide (NO2): 5 ppm 6 hours
0 - 15.0 ppm Nitrogen dioxide (NO2): 10 ppm 6 hours
O2 (Oxygen) 0 - 5.00% Oxygen (O2): 2% for span
Nitrogen (N2): 100% for zero
10 minutes
0 - 25.0% Fresh air for span
Nitrogen (N2): 100% for zero
3 hours
PH3 (Phosphine) 0 - 1.00 ppm Phosphine (PH3): 0.5 ppm 6 hours
SiH4 (Silane) 0 - 15.0 ppm Silane (SiH4): 5 ppm 6 hours
SO2 (Sulphur dioxide) 0 - 6.00 ppm Sulphur dioxide (SO2): 5 ppm 3 hours
Calibration Equipment
• Demand flow regulator (RKI Instruments, Inc. recommends that you dedicate one regulator each
for Cl2 and H2S and that you not use that regulator for any other gas)
• Calibration tubing
• Calibration cylinder of appropriate concentration
Preparing for Calibration
GAS IN Fitting
Remove the dust filter and the sample line from the GAS IN fitting’s tubing stub.
Regulator
Screw the demand flow regulator onto the calibration cylinder.