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11.2.2 Cleaning of Conductivity of Electrodes
Platinised platinum Conductivity electrodes can only be cleaned by rinsing in a
suitable solvent.
DO NOT wipe the electrode wires
, as this will remove the
platinum-black layer.
1. Rinsing in distilled water will remove most build-ups of material on the
electrode wires.
2. Films of oils or fats on the electrode wires can usually be removed by rinsing
the electrode in methylated spirits.
3. Stubborn contamination can be removed by soaking the electrode in a solution
of 1 part Concentrated HCl and 10 parts distilled water. The electrode should
not be soaked for more than approximately 5 minutes, otherwise the platinum-
black layer may start to dissolve.
4. If all of these methods fail, then the last resort is to physically scrub the
electrode wires, which will remove the contaminant and the layer of platinum-
black. Use only a cloth or nylon scouring pad. DO NOT USE STEEL WOOL.
The electrode will then need to be cleaned in HCl, as per step 3 and
replatinised, as per section 11.2.3.
