Disinfection validation requirements based on the Spaulding classification for medical devices. Blog post by Sneha Mistry

January 3, 2024

Disinfection validation confirms that the disinfection process eliminates or reduces harmful pathogens. Disinfectants used in the pharmaceutical and medical device industries must be validated for their intended use. Disinfection is a process that reduces the number of microorganisms to a level at which they do not present a risk to patients or clients. A regulatory expectation is to ensure the appropriate disinfectant is employed and microbial control is maintained.

What is disinfection validation?

Disinfection Validations are used to validate the device manufacturer's disinfection instructions. Validations may be performed to support high-level, intermediate, and low-level disinfection processes depending on the device's intended use. The level of disinfection is determined by the Spaulding Category of the device, critical, semi-critical, or non-critical.

What is the Spaulding Category of the device?

Spaulding classification separated patient care items into three categories critical, semi-critical, or non-critical.  Critical medical devices come in contact with the bloodstream and sterile parts of the body.  These devices must be sterilized.  Semi-critical devices come into contact with intact mucous membranes or non-intact skin but do not normally penetrate the blood barrier or sterile area of the patient.  Semi-critical devices should be sterilized, but high-level disinfection may be used if the device cannot withstand sterilization. Non-critical devices only contact intact skin.  Non-critical devices can be disinfected using intermediate or low-level disinfection.

Method Outline:

Devices are inoculated in the worst location which is the most difficult area to clean. The sites are inoculated with an appropriate concentration and type of microorganisms and allowed to dry. Disinfection is performed on the inoculated test device according to disinfectant IFU, followed by a bioburden recovery process to determine the number of microorganisms left on the medical devices. Test devices recovery compared to a positive control device for the log reduction.

Acceptance Criteria:

High-Level Disinfection:                 

• 6-log reduction of Mycobacterium spp.

 Intermediate-Level Disinfection    

• 6-log reduction Klebsiella pneumoniaes

• 6-log reduction Pseudomonas aeruginosa

• 6-log reduction Staphylococcus aureus

• 6-log reduction Escherichia coli

• 3-log reduction of Mycobacterium spp.

Low-Level Disinfection:

• 6-log reduction Klebsiella pneumoniae

• 6-log reduction Pseudomonas aeruginosa

• 6-log reduction Staphylococcus aureus

• 6-log reduction Escherichia coli

References: 

- Food and Drug Administration 2015/(R)2017. Guidance for Industry and FDA Staff –Processing/Reprocessing Medical Devices in Health Care Settings: Validation Methods and Labeling. U.S. Department of Health and Human Services, Washington, D.C.

- AAMI TIR12:2021 Designing, testing, and labeling reusable medical devices for reprocessing in health care facilities: A guide for device manufacturers.  Association for the Advancement of Medical Instrumentation, Arlington, VA.