Maintanence

Stainless steel is naturally corrosion-proof and needs no additional protective coating to maintain its gloss and usability for a long time. A certain amount of routine maintenance involving cleaning and washing may be required, however, to retain the steel surface’s original aesthetic, corrosion-proof qualities. In this respect, stainless steel is no different than other building materials such as glass, plastic or coloured steel, which also require maintenance during the building’s service life.

The following guidelines are tips for property owners, caretakers and administrators on how to clean the product cost-effectively to exploit the fine corrosion-proof qualities of stainless steel.

Maintaining and cleaning stainless steel
The frequency with which indoor stainless steel surfaces should be cleaned is actually no different than other materials. The surfaces should be washed before accumulated dirt or fingermarks become obvious which will also make the cleaning as easy as possible and minimise the risk of leaving marks behind or affecting the surface finish.

Outdoors, stainless steel is exposed to a more aggressive environment if exposed to:

* a maritime atmosphere;
* an industrial atmosphere;
* spatter from road salts;
* air pollution and car fumes.

All of these environments can cause brown spots to appear. A good rule of thumb is to clean the stainless steel surfaces just as often as the building’s windows. Depending on the degree of contamination from the surroundings, an interval of six to twelve months is recommended for light contamination and three to six months for more severe conditions, such as those mentioned in the above. Cleaning agents containing phosphoric acid can be used for removing this type of spotting.

Cleaning agent
A damp rag or a chamois cloth is usually sufficient for wiping away light dirt, fingermarks and the like.

For tougher spots, a cleaning sponge like “Scotch Brite” is often appropriate. Do not use mesh balls of metal wire (not stainless steel), steel wool or metal brushes to clean stainless steel. Not only will they scratch the stainless steel surface, but they will also leave behind carbon steel particles that will form rust spots when the surface gets wet.

It is better to use a soft nylon brush for cleaning patterned stainless steel. Do not use steel brushes made of any other material besides stainless steel.

For stainless steel with a polished finish with visible polishing grains, clean the steel with the grain – not against the grain. When water has been used for cleaning or rinsing, wipe the surface dry to prevent water from drying and forming watermarks, especially in areas with hard water. Avoid this type of watermark by using distilled water.

To avoid transferring contamination in the form of iron particles, make sure the cleaning material was not used for cleaning ordinary steel (carbon steel) previously. It is best to use cleaning materials designed specifically for use on stainless steel.

To remove fingermarks and similar spots on indoor stainless steel surfaces, soapy water or a mild dishwashing detergent will usually give reliable and rewarding results.

Spray cleaners available on the market make cleaning easy and also leave a thin film for polished effect. Such spray cleaners remove fingermarks and reduce the tendency for new marks to keep forming. Buff with a soft dry cloth or rag.

Discoloration must be removed mechanically using a nylon sponge like “Scotch-Brite” which is used in kitchens. Alternatively, it is possible to use retail cleaners containing phosphoric acid that are intended for use on stainless steel.

Stainless steel with a mirror finish can be cleaned using window cleaners. They should not contain chlorides (common salt), however.

For tougher spots, creamy polishers like Vim cream, can be effective. These can also be used for wiping off water spots and can alleviate discoloration. Remove this type of residue by rinsing with clean water (preferably the type of distilled water used for steam irons and car batteries) and wipe away any remaining streaks of polish or watermarks. Do not use scouring powder as it will scratch the stainless steel surface.

Tough grease or oil marks can be removed using denatured alcohol or acetone. There is no risk of corroding stainless steel by using such solvents. Be careful to limit the amount of solvent used, to avoid spattering the spots over a larger area, which makes the cleaning more difficult. For this reason, it may be more expedient to wash more than once using a pure solvent on a clean soft rag until all traces of the greasy residue are gone.

Paint and graffiti can be removed by using ordinary soda solutions?? or paint removers??. Do not use paint scrapers or knives to remove dirt/spots as they will easily scratch the stainless steel surface.

Badly neglected surfaces can be cleaned with a metal polisher used for cleaning chromium-plated surfaces (such as on cars). Also the type of polishing agents used for polishing car enamel can be considered. Be careful, however, because mirror-finish surfaces can be scratched by this type of polisher.

Alternatively, use a special cleaner containing phosphoric acid designed for stainless steel, followed by rinsing with distilled water and wiping dry. It is advisable to treat the entire surface of the component to avoid the risk of a blotchy surface.

Do NOT use the following cleaning agents to clean stainless steel:

cleaners containing chloride;
bleaches containing hypochlorite (if accidentally spilled on stainless steel, rinse off immediately using copious amounts of water);
silver polish.

Regular cleaning
For outdoor installations, such as façade components, rain will usually wash off accumulated dirt and other coatings if the surfaces are sufficiently and freely exposed. Be particularly aware of surfaces protected by a roof when performing routine cleaning to flush off areas of accumulated airborne particles. This is especially important in maritime and industrial environments where particles containing chlorides or sulphur oxides can accumulate and cause local corrosion if not removed effectively.

Indoors, fingermarks on installations are undesirable. Stainless steel comes in many different surface designs, many of which are well suited in heavily trafficked public environments. By choosing a surface finish that is less sensitive to fingermarks already at the design phase, it is possible to reduce the need and cost of cleaning during the entire service life of the building.

Brushed surfaces are often a popular choice for indoor application, but can be marred by fingermarks soon after installation. After a couple of cleanings, however, such marks will gradually become less prominent.