Reusable Medical Device Disinfection Validations

Low, Intermediate and High-Level Disinfection Validation for a Reusable Medical Device

  • AAMI Method TIR12
  • AAMI TIR30

Purpose of Test

The U.S. FDA requires that disinfection instructions supplied by medical device manufacturers to the end-users of reusable medical devices be validated to assure that they are appropriate for the device. AAMI Technical Information Reports (TIR) 12 and 30 are referenced to establish appropriate test protocols designed to validate these disinfection instructions. Based on the Spaulding Classification established by the Centers for Disease Control and adopted by the FDA, reusable medical devices are classified as either critical devices, semi-critical devices or non-critical devices. Based on these classifications, the U.S. FDA requires that the disinfection instructions meet either low-level, intermediate-level or high-level disinfection standards.

Summary of Test

In these studies, test devices are subjected to soiling conditions (comprised of the test organism typically containing an organic soil load) which is designed to simulate worst-case contamination conditions in which the device would face during clinical use. The devices are then disinfected as directed and are assayed for surviving test organism. The resulting plates are incubated and the survivors are enumerated. Log10 reductions are determined for the disinfected devices as compared to an untreated population control device. Depending on the level of disinfection required, 3 log10 or 6 log10 reductions must be observed. Common test organisms evaluated in these studies include: Klebsiella pneumoniae, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and Mycobacterium terrae.