PH Meter Cleaning Procedure

PH Meter Cleaning Procedure

• Proper cleaning of the pH electrode begins with storage, which can increase the service life.
• Combination and reference electrodes with electrolyte liquid should be stored in the same aqueous solution.
• Gel electrodes should be stored in 3 mol/l KCl solution, while glass electrodes require storage in deionized water.

Storage Duration

• Short-term storage: Tap water or storage solution for a few hours or days.
• Medium-term storage: Storage solution for several days.
• Long-term storage: Dry storage for several weeks or months, followed by soaking in storage solution for several hours and calibration.

Cleaning Solutions

• Standard solutions: Alkaline surfactant and polyphosphate solution, sodium hypochlorite solution, and phosphoric acid for general application and common contaminants.
• Specific solutions:
  • Ethanol, acetone, or alkaline surfactant and polyphosphate solution for greases and oils, meat fat, and ink stains.
  • Pepsin/HCl solution for proteins.
  • HCl or caustic soda solution for inorganic substances.
  • Sodium hypochlorite solution for blood products, beer and wort residues, milk sediment, and dairy products.
  • Thiourea solution for blood products and beer and wort residues.

5-Step Cleaning Process

• Step 1: Rinse with distilled water after measurement to remove superficial residues.
• Step 2: Immerse in a suitable cleaning solution until the visible diaphragm appears clean.
• Step 3: Replace internal electrolyte fluid if possible.
• Step 4: Soak in storage solution for two to three hours.
• Step 5: Perform a new calibration at regular intervals or after a longer storage period.

Important Notes

• Avoid mechanical procedures (rags, brushes) to prevent damage to the sensitive surface.
• Extend immersion and watering intervals if soils remain visible after cleaning.
• Types of buildup and contamination depend on frequency of use, type of electrode, and test sample.