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How to use citric acid to clean a steam sterilizer

How do I use citric acid ⇦ this on eBay or Amazon [affil links] to clean/descale a steam sterilizer as this is what it suggests I use according to the sticker on the side.

Dwayne Williamson

2006

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If by scale you mean mineral (calcium, magnesium) deposits from hard water, you may be able to remove these with citric acid , but it will take longer than with mineral acids (but will be safer). If you mean to remove metallic oxides/scale (form welding, possibly), citric acid will not work. You will have to use a stronger acid or mechanical methods. citric acid will passivate stainless steel, passivation in this use means to remove "free" iron from the SS surface. You could consult ASTM A967 and/or ASTM A380 , or contact the sterilizer manufacture. Good Luck.

Thomas Kemp

2006

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2006

Dwayne:

citric acid could be used to de-rouge steam sterilizers, however it may require extensive contact time, even at 80 degrees C. Light accumulations of rouge can be removed with citric acid , but heavy accumulations will probably require addition of stronger organic acids (like oxalic) or phosphoric acid in order to complete in less than 24 hours. Caution must be exercised when using stronger de-rouging agents if the stainless steel is highly polished or electropolished. Etching of the surface may result from strong de-rouging solutions. Routine cleaning of the unit is recommended to avoid excessive accumulation of rouge.

Good luck,

Daryl L. Roll

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I would like to know how to use the citric acid when descaling the lime scale in my baby's steriliser, it recommends citric acid but doesn't say how much to use or what to do with it, any idea?

Claire Carass

May 12, 2008

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30 gms citric acid in 500 mls of water.

This may be boiled

John long

October 19, 2010