The Use of Tap Water When Cleaning Electrodes

[vanv0076]

Hello BioSemi. I've noticed in other posts that tap water has been approved for cleaning electrodes, but what about if the water is visibly contaminated with iron/rust? I'm in the process of setting up a new EEG lab and the water that we would use to clean the electrodes has an orange-ish tint. Considering that I've seen other posts that advise against letting the electrodes contact metal I'm not sure whether or not this water has too much metal in it. Thanks!

[Coen]

The electrodes should be tested in clean water with a little salt (something like a teaspoon per liter). Care should be taken to not pollute the electrodes with traces of (non silver) metal. In most case, using tab water, table salt, and a plastic or glass bowl is sufficient. However, if you suspect that you local tab water is polluted with iron (or other traces of metal), than I would certainly use distilled water instead. Bottled mineral water is not recommended either.

Pollution of the Ag-AgCl electrode tips will lead to increased noise, especially at the low frequencies (high and unstable offsets).

Best regards, Coen (BioSemi)

[vanv0076]

Okay, we will try to find another water source for cleaning the electrodes. Thanks for the help!

[Simone24]

It's crucial to address the issue of using visibly contaminated water for cleaning electrodes, especially in a sensitive environment like an EEG lab. While tap water is generally approved for this purpose, the presence of visible rust or iron in the water raises concerns about its suitability. The orange-ish tint indicates a significant amount of metal, which could potentially interfere with electrode performance or even compromise data accuracy. Given the advice against electrode contact with metal, it's prudent to err on the side of caution and seek alternative cleaning solutions or ensure the water undergoes appropriate filtration or purification processes to remove contaminants. For more information on NYC tap water, you can check out this link: https://www.nyrentownsell.com/blog/nyc-tap-water/. Maintaining the integrity of the EEG setup is paramount for reliable results and accurate readings.

[anatolewilson]

You're absolutely right to be cautious about using rusty or visibly contaminated tap water for cleaning EEG electrodes.