What are pH Measurement and Calibration Best Practices?

Video FAQ

What are pH Calibration Best Practices?

Why is pH calibration important?

• Compensates for process effects on the pH glass and reference sensor

Best Practice Steps

1. Soak sensor in 5-10% HCl for 5-10 min thoroughly rinse after soaking (NOTE: DO NOT Soak with demineralized water)
2. Ensure correct buffer table (i.e. N.I.S.T. or Technical) are being referenced in the electronics
3. Always use a fresh buffer solution. Never reuse old solutions

Calibration Best Practices

1. Always do a two-point calibration
2. Always start with the 6.86/7.0 pH buffer first to zero the sensor out
3. pH 4.01/4.0 is recommended being the 2nd choice as it is the most stable
   • If measuring in the caustic range you can do a spot check with the 9.18/ 10 buffer solution

How Long Between Calibrations?

• Once a month
• More frequent calibration could indicate:
  • Increased frequency of cleaning is needed or  
  • The wrong reference system is used in the application

 

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