Despite stainless steel is corrosion-resistant, incorrect handling can cause it to corrode and discolor? Erase the discoloration with a pencil eraser to see if it is rust or just a stain. Corrosion is present if there is pitting in the metal beneath the discoloration. If the discoloration is removed, it will be shown to be a stain.

 STAIN GUIDE FOR STAINLESS STEEL:

•  A high pH can colour surgical equipment brown or orange.
• If a stain is dark brown, it is likely that the stainless steel surgical instruments were exposed to a low pH solution.
• Reverse plating could result in a blue or bluish-black discoloration. This can occur if metals are mixed during a cleaning procedure. Stainless steel instruments, for example, should not be coupled with titanium equipment. Dissimilar metals (stainless steel, copper, chrome-plated, titanium, etc.) should not be cleaned in the same cleaning cycle.
•       Excessive heat causes a multi-colored discoloration.
•       Water droplets that dry on the surface of surgical equipment can form light or dark stains on instruments.
•       When medical equipment comes into touch with ammonia, they develop black stains.
•       Excessive use of a rust removal solution may impair the polish and leave a grey stain on surgical instruments.
•       If your surgical equipment develop a rusty tint, it is most likely from dried on blood or bio-debris. Always promptly rinse off all blood, body fluids, and tissue after usage. Dried dirt might harm the instrument's surface and make cleaning more difficult. Use cold water instead of hot water since proteinous compounds will coagulate. Soak the instrument in an appropriate cleanser to release any debris before removing the stain. Then, proceed with a manual cleaning procedure.