[lifeofgrime]

Hi all,

We are currently carrying out some cleaning works in a commercial premises who have large industrical stainless steel appliances.

In the past, we've noticed that some of the products which have been used by third parties leave a brown stain on the steel - does anyone have any idea what can cause stainless steel to stain?

It has always been the thought that its the orange pigment used in the citrus-based cleaner we use, but I'm beginning to wonder whether it boils down to the methodology which some cleaners are using to tackle certain aspects of their cleaning - i.e. using sodium hydroxide solution on work tops.

Would this penetrate the metal and therefore make the stainless steel vulnerable to oxidising - hence the brown stain?

Any ideas would be much appreciated - and, if you know of anything which is good for removing grease and grime from stainless steel worktops etc, that would be ideal

Thanks!

[DP]

In short yes, its perfectly ok to use an acid based chemical with stainless (if you must) so long as it is completely rinsed, neutralised and re-nourished i.e. oiled same as zinc.

The problem comes when residual chemicals are left behind which continue to work (sloppy cleaning). You wont penetrate the surface, appliance/worktop panels are usually stainless or polished aluminium being  continuous  materials, however you can easily erode (spoil) the texture or corrode (by reaction) the surface and cause staining.

With both of these types of material, you should never use a chemical that is stronger then it needs to be and always rinse, or use an alcohol based product for routine cleaning, such as some types of window and tile cleaner or specialist s/steal cleaner. Remember stainless will dry badly and may need re-oiling (but not worktops). Re worktops, the ideal would be boiling water or a steamer with as little chemical as possible.

[The Great One]

Hi

had this a while ago.

the browning is tarnishing left over by an acid which has been used and not rinsed off properly.

go to local hardware shop buy Bar Keepers Friend (£3.49) put on with scourer and a little water, leave for 1 minute and rinse off, another application may be needed. Once rinsed off buff up with paper towels and windowlene. Comes up a treat.

They will think you are Jesus and be happy.

Regards

Martin

[S C Solutions]

just some advice, you should never use a scourer on stainless teel as it scratches the surface and bacteria will build up and contaminate food prepared on the surface. just use a strong degreaser with a dish cloth or towel, rinse thoroughly and polish with a good quality stainless steel food safe polish. a firm called chemex do a good one.