Cleaning Guidelines for Stainless Steel
Keeping up Appearances
For stainless steel components where an attractive appearance is particularly important such as building cladding, shop entrances and signs; regular cleaning is advisable in order to maintain the prime condition of the material.
Washing also removes dirt and impurities that may cause corrosion to stainless steel and discolouration of the metal surface if left in place too long. The more polluted the environment, the more often such washing of the stainless steel should be carried out.
The intervals between washing should be determined from the local environment and from experience, but generally the following guidelines should be observed.
||Recommended Washing Intervals
| Type 304
|| Type 316
|Clean inland location
|| 3-6 months
|| 6-12 months
|Polluted urban area / internal location / industrial
|| 3-6 months
|Coastal location / Marine
|| 3-6 months
Washing of stainless steel is best carried out with soap or a mild detergent and warm water followed by rinsing with clean cold water.
The appearance of the stainless-steel surface can be improved further if the washed surface is wiped dry.
Stainless steel is easy to clean. Washing with soap or mild detergent and warm water followed by a clear water rinse is usually adequate for domestic and architectural purposes.
Where stainless steel has become extremely dirty with signs of surface discolouration, alternative methods of cleaning can be used as outlined on the next page.
In environments where there is heavy use of aggressive contaminants such as chemicals, salt or de-icing salts, then high frequency cleaning every second month is recommended.
||Suggested Cleaning Method
||Soap, detergent or dilute (1%) ammonia solution in warm clean water. Apply with a clean sponge, soft cloth or soft-fibre brush then rinse in clean water and dry.
||Proprietary traffic film removers (TFR) as used for cleaning cars show good results and are easily removed to leave a streak free finish. e.g. Autosmart “Active XLS”.
||Detergent and warm water. Alternatively, clear liquid bleach free window cleaners.
bleach free window cleaners.
e.g. “Mr Muscle”.
|Stubborn spots, stains and light discolouration. Water marking. Light rust staining.
||5% phosphoric acid solution then rinse in clean water and dry.
||Proprietary cleaning products are available e.g. Vecom “Vecinox” stainless steel cleaner.
|Heavier staining or
|10% phosphoric acid solution, followed by ammonia and water rinses.
||Proprietary cleaning products are available from a number of companies e.g. Vecom “Vecinox” stain remover.
|Adherent hard water scales and mortar/cement splashes
||10-15 volume % solution of phosphoric acid. Use warm, neutralise with dilute ammonia solution, rinse with clean water and dry.
||Proprietary formulations available from a number of companies e.g. “Vecom”.
|Paint or graffiti
||Alkaline or solvent paint strippers, depending upon paint type. Use a soft nylon brush on patterned surfaces.
||Proprietary products are available from a number of companies e.g. Vecom.
- When cleaning a surface with any chemical preparation, a trial should be undertaken on a small, unobtrusive hidden or non-critical area of the surface, in order to check that the resulting finish still matches with the original.
- The products referenced in this documentation are understood to be suitable for stainless steels. However, no endorsement of the products or their manufacturers is implied. It is acknowledged that other manufacturing companies may provide products of equal or better quality.
- Cleaning agents should be approved for use under the relevant national environmental regulations and, in addition, prepared and used in accordance with the manufacturers’ or suppliers’ instructions. Solvents should not be used in enclosed areas.
- To avoid water marks, use clean rinsing water, such as reasonable quality potable (tap) water. Drying marks may be avoided using an air blower or wiping with clean disposable wipes.
- Chloride-containing solutions, including hydrochloric acid-based cleaning agents and hypochlorite bleaches can cause unacceptable surface staining and pitting and should not be used in contact with stainless steels. Under no circumstances should concentrated bleaches come into contact with decorative stainless-steel surfaces. Hydrochloric acid-based solutions, such as building mortar removal solutions, must not come into contact with stainless steel. Hypochlorite containing bleaches must be used in the dilutions suggested in the manufacturers’ instructions and contact times kept to a minimum. Thorough rinsing after use is important. A frequent cause of staining and micro pitting of stainless steel is a direct result from splashing of undiluted bleach solutions and mortar cleaners.
Rimex Metals cannot accept responsibility for any problems or damages arising as a result of these suggested methods of cleaning.
- Cleaning agents containing bleach should not be left in contact with stainless steel. This includes many of the ‘trigger-dispenser’ cleaning products. If bleach is necessary it should be used only in the strengths prescribed by the manufacturer and never soaked for longer than 15 minutes, after which the stainless-steel surface should be thoroughly rinsed with clean water.
- Harsh abrasives and scouring materials should not be used for cleaning stainless steel as they will leave scratch marks on the surface and damage the appearance of the article. Likewise, do not use wire brushes, scrapers or contaminated scouring pads.
- If the article has a directional polished grain, any cleaning with abrasives should be carried out along the direction of the grain and not across it.
- After use, always remove wet cleaning aids (such as cloths, pads, containers) from the surface, to avoid formation of water marks/stains.
- Strong acids such as sulphuric and hydrochloric are very corrosive and should not be allowed to come into contact with stainless steel.
Protective Tape Residue
After the removal of protective tape from supplied materials, it is possible that adhesive residue is left behind. Fortunately, this does not happen often but it is possible.
In such circumstances the general advice from Rimex’s protective tape suppliers, Poli-Film and Nitto Adhesive Tapes, is to clean away the adhesive residue using Acetone or a similar product with a soft cloth and afterwards to rinse the affected area with water.
It is always recommended that you first test your cleaning method on a non-visible area of the material in case there is an adverse effect to the material or its surface.