Your first-line-of-defense against Preventing Corrosion is maintaining the passive layer of Surgical Instruments. Stainless steel surgery instruments are made of corrosion resistant high-grade specialty steels. The key word here is resistant. Corrosion resistant does not mean corrosion proof. One of the special characteristics of these steels is that the manufacturer forms a passive oxide layer on the surface, which protects them against corrosion. This makes surgery instruments as corrosion resistant as possible. It is imperative that you maintain the passive oxide layer to prevent corrosion and maintain your surgery instruments in optimal condition. If this is not done the stainless steel will be more susceptible to corrosion, pitting and stains.This will reduce the life of the surgery instruments and/or render it useless. Initially, all “stainless steel” surgical instruments have the same corrosion resistance. When strength and hardness requirements are important factors for instrument function, corrosion resistance is generally lower. Increasing the corrosion resistance would soften the stainless steel. Manufacturers of surgery instruments and surgical instrument containers recommend the use of neutral pH cleaning concentrates. Newly developed neutral pH all-in-one or "combination detergent" cleaning concentrates have been shown to be effective in optimizing the efficacy of the "passive oxide layer". This will provide a longer life for stainless steel surgery instruments. Cleaning concentrates with a high or low pH have been shown to erode the passive layer. Neutral pH Surgical Instrument Cleaning is recommended by Manufacturers of Surgical Instruments all manufacturers of surgical instruments, rigid scopes, flexible scopes, and instrument containers recommend the use of neutral pH Cleaning Concentrates. Surgical Instrument Cleaning Disinfection Sterilization of Surgical Instruments Surgical Instrument Cleaning Clean instruments, or apply treatment to prevent the drying and encrustation of debris, as quickly as possible after use. Ultrasonic Cleaning when Surgical Instrument Cleaning Ultrasonic cleaners are very effective when used with hot water per manufacturer’s recommended temperature and specially formulated detergents. It is recommended that all visible debris and blood be removed from the instrument prior to ultrasonic cleaning. Contact between dissimilar metals can cause corrosion when Ultrasonics is applied.
Stainless steel is essentially a low carbon steel which contains chromium at 10% or more by weight. It is this addition of chromium that gives the steel its unique stainless, corrosion resisting properties. The chromium content of the steel allows the formation of a rough, adherent, invisible, corrosion-resisting chromium oxide film on the steel surface. If damaged mechanically or chemically, this film is self-healing, providing that oxygen, even in very small amounts, is present. The corrosion resistance and other useful properties of the steel are enhanced by increased chromium content and the addition of other elements such as molybdenum, nickel and nitrogen. Stainless steel has a passive film created by the presence of chromium (and often other alloying elements, nickel, molybdenum) that resists this process. When exposed in air, stainless steels passivate naturally (due to the presence of chromium). But the time required can vary. In order to ensure that the passive layer reforms rapidly after pickling, a passivation treatment is performed using a solution of nitric acid and water.
How is the "passive oxide layer" Manufactured and Maintained