304-grade stainless steel may be the best choice for a railing system designed for both indoors and outdoors – especially if your application is away from large bodies of salt water and won't be exposed to extreme conditions
Pros: Resistant to ordinary rust and corrosion.
Cons: Can corrode in chlorinated or salty environments.
Best Used For: Indoor or protected railings
Maintenance: Regular cleaning with soap and water.
304 stainless steel is usually used for indoor applications. If the color is required, it will readily accept a paint or powder coating, but this grade of steel generally does not require a protective coating, and finishes ranging from satin to more elaborate options such as mirrors can be used instead. In addition to aesthetics, these finishes are practical; for example, satin finishes are easy to maintain, while mirror finishes are extremely resistant to corrosion.
▲We recommend 316 stainless steel if your outdoor railing will be in a demanding marine environment (on or very near to the ocean/salt water).