A majority of health departments and other regulating agencies require stainless steel equipment for food service applications.  Most restaurant sinks are made from type 430 or type 304 stainless steel, which are generally acceptable in most areas (these are specified per item if your health department may have further restrictions).  Type 304 stainless steel indicates a higher nickel content which improves the corrosion resistance.  The gauge of stainless steel  indicates thickness; the lower the gauge number the thicker the stainless steel.  A restaurant sink constructed of 16 gauge type 304 stainless steel will resist corrosion longer and provide a better return on your investment than a less expensive restaurant sink constructed of 18 gauge type 430 stainless steel.  All stainless steel restaurant sinks, although top of the line commercial grade stainless steel, can corrode and decay when they are misused or exposed to extreme environmental conditions.

Stainless steel can corrode, or rust, when exposed to excessive and high humidity, as found in some southern coastal locations.  The salt air found in all coastal regions can also create problems with these sinks if they are not properly maintained.  Water from wells may also be detrimental to stainless steel because of the high sediment levels.  However, the majority of the corrosive issues stem from misuse or lack of a maintenance program.

Most restaurants use a 3-compartment sink, so they can use a 1-2-3 Wash System.  This system is ideal for sanitization, the first step being to wash with a detergent, the second step to rinse, and the third to sanitize.  This system can however lead to corrosion of your stainless steal sink.  The use of chlorinated sanitizing chemicals, such as bleach, or a lot of detergents, can actually eat away at the stainless steel, if the solution is left to sit in the sink.  This is not to mean you cannot use these detergents, although detergents with low chlorine levels are preferred. 

So what kind of maintenance program can you adopt to ensure the longest life possible for your sink? 

When you have used your sink with any detergent or bleach, it is best to rinse the sink bowl off completely after you have let it drain.  The next step is to simply dry off the sink bowl.  Drying the sink bowl eliminates sitting water.  Pinholes can still form in your sink basin if they are rinsed but not dried, because small amounts of water, mixed with latent chemicals, sit and air dry, as they eat away at the stainless steel.