Stainless-Steel has become trendy in residential design and commonly found in many areas of the home and commercial setting but setting aside fashion, Stainless-Steel is the preferred surface for infection control and corrosion control.
Here is the key thing you need to know: Not all Stainless-Steel items are created equal; there are varying grades, different finishes and different fabrication techniques that all play into the quality and lifespan of anything stainless-steel.
Stainless Steel comes in several grades that indicate the percentages of materials and the compositions of alloys, which most consumers do not understand. Without getting into a science lesson, it is important for you to understand that stainless-steel can and will corrode in some grades while others will not. With the large volume of consumer products being mass produced in a competitive economy, you can be sure that any and all corners are cut to reduce the cost of manufacturing. The raw materials cost of the best stainless steel is three to four times the price of the basic grades of stainless-steel.
The finish is not very likely to change the corrosion properties however, it is possible to harbour residual water that has minerals in it which are prone to rusting. In this case, your stainless-steel may only be harbouring minerals or sediment that is rusting on top of the surface. This can usually be simply polished off using a metal polish without affecting the metal itself but if it has done it once, it will continue to do so and will require regular cleaning and occasional polishing.
Fabrication plays a much bigger role than most would realise. Stainless-steel products should be fabricated on machines that are used exclusively for stainless-steel. Mixing metals on metal formation and cutting machines can infuse metals from the other products into the stainless-steel, including the metals that will rust and corrode. It is also noted that stainless-steel will react adversely when mixed with some other metals resulting in corrosion. That is why you will find in areas where infection control is of concern, the stainless-steel products are typically solid stainless-steel without mixed metals.
In summary, it is a “buyer beware” situation. In the healthcare industry, you should never take less than a type 304 with a #4 finish, from a company that exclusively works with stainless-steel. For pharmaceutical applications, it should be type 316 stainless-steel and nothing else! I can’t count the number of times where I have seen food grade equipment (200 series) being used for decontamination sinks in the sterile reprocessing department of a hospital. Although the temptation is great, buying cheaper products that are the wrong grade will not give you the sterile properties and the non-corroding surface that is necessary for sterile applications.