SS316L is a surgical implant grade, which is the most used material for Body Jewelry. The two most common standards that apply to body jewelry made of steel are ASTM F138 and ISO 5832-1 which describe the qualities of steel for surgical implants.
The element in stainless steel that causes allergic reactions in some people is nickel. Polishing the jewelry to a mirror like luster results in a protective layer of chromium oxide, which reduces the release of the Nickel content into the tissue. Surgical Steel can be sterilized in an autoclave.