FD-90A

Calibration of FD-90A

Summary:
A step-by-step tutorial on calibrating your FD-90A toxic gas detector. 

Model: 
FD-90A. Versions CO, H2, H2S, PH3, Cl2, O3, Br2, SO2, NO2, EX, NH3, CO2, VOC, ACID, ALCOHOL, HCl, HF, C2H4, C2H2 and many others. Except for FD-90A-O2.

Calibration Frequency: 
At least every 12 months.

Calibration Kit Items Required:

  1. Calibration Gas Bottle
    • Select the corresponding calibration gas for your unique gas detector. To do so, go to the product listing of your gas detector for the recommended calibration gas bottle.
  2. Calibration Gas Regulator (C10)
  3. Tubing

▶️ Tutorial Calibration Video

 Example: FD-90A-CO

Note: Example of Carbon Monoxide (FD-90A-CO). Each FD-90A is unique and made to a specific single target gas. Follow this procedure using the recommended calibration gas bottle for your particular target gas.

✅ STEP 1: ZERO Calibration to 0 ppm using Fresh Air.

  1. Power on your gas detector and allow 2 minutes for stabilization in fresh air.
  2. Expose the gas analyzer to fresh air or pure nitrogen for at least 2 minutes. 
  3. If using a N2 gas bottle, use a flow rate of 0.5 LPM.
  4. The gas detector may or may not read precisely 0 ppm. Depending on the model, it may or may not read 0.0 or 0.00 ppm. To zero calibrate and make it read exactly 0, 0.0, or 0.00 ppm, undertake the following steps.
  5. Press the middle button to go to the Menu Screen.
  6. Select "Gas Zero" by pressing the middle button.
  7. Then press "Save".
  8. Done! 
  9. In the main display screen, the unit will now read 0 ppm in fresh air.

✅ STEP 2: SPAN Calibration.

  1. Ensure you first undertake a Zero Calibration.
  2. Then, expose the gas analyzer to your calibration reference gas for 2 minutes or until the reading has stabilized. Use a flow rate of 0.5 LPM and connect the gas to the gas detector via the FD-90A calibration cap.
  3. Select "Gas Calib" from the Menu Screen.
  4. Enter passcode: 8888.
  5. Enter the span reference gas value for calibration, which is the same value shown on your gas bottle or, more precisely, on your calibration gas bottle Certificate of Analysis.
  6. Then press "Next".
  7. The display shows the detected gas value. Ensure this has stabilized.
  8. Then press "Save".

  9. The analyzer is now span-calibrated, and the calibrated value is shown on the main screen. 

✅ STEP 3: Verification

  1. Allow the gas detector to stabilize in fresh air for 5 minutes, confirming it reads 0 ppm in fresh air.
  2. Expose the analyzer to the calibration reference gas to verify the calibration and detection repeatability.
  3. If the gas detector reading is within +/- 2% F.S. of the calibration gas value, this is considered a PASS. For example, FD-90A-CO has a full scale of 1000 ppm. The unit was calibrated to a reference gas of 200 ppm. Then, a PASS range is +/-2% of 1000 ppm = +/- 20 ppm. Therefore, a PASS is between 180 ppm and 220 ppm. 
  4. Once verified, your unit is properly calibrated and ready for operation.
  5. Don't forget to document the calibration event in your gas analyzer log book. Place a reminder calibration date sticker on the unit for the next calibration event.