Medical Device Regulation Basics: Sterilization

Sterility is a state of being free from viable microorganisms

Medical devices are produced as per medical device quality requirements are also may have low number of microorganisms prior to sterilisation .These products are called nonsterile products.

Products are sterilized to inactivate the microorganisms to transform nonsterile products to sterile products. Sterile products are free from viable microorganisms.

A strategy for sterilization or disinfection of inanimate objects and surfaces based on the degree of risk involved in their use.

EH Spaulding provided a strategy for sterilization or disinfection of the device based on their intended use .

Classification	Type of contact	Sterilization/Disinfection
Critical	Sterile tissue or the vascular system	Sterilization
Semi‐critical	Contact mucous membranes or non‐intact skin	High‐level disinfection
Non‐critical	Contact intact skin but not mucous membranes	Low‐level disinfection

Medica devices are either terminally sterilized or aseptic processing

S.No	Terminal sterilization	Aseptic processing
1	it is a condition of a medical device which has been exposed to a sterilization process in a packaged or assembled form that maintains the sterility of the medical device or a defined portion thereof.	Medical device components are sterilized individually and then assembled in clean room
2	Risk of contamination is low because product is fully sealed	Risk of contamination is high
3	State of sterility for terminally sterilized medical devices is defined using sterility assurance level (SAL) of 10⁻⁶ or less (e.g. 10⁻⁷) .Probability of there being a viable microorganisms present on/in the device shall be equal to or less 10⁻⁶	Difficult to achieve the SAL f 10⁻⁶ or less (e.g. 10⁻⁷) as accidental contamination caused by inadequate technique cannot be reliably eliminated
4	Physical methods: --Steam,dry heat --Radiation Chemical methods: Ethylene oxide, Hydrogen perioxise	Filtration