Chemical and Autoclave Sterilization Methods Outlined in Annex III of the WHO Infection Control Guidelines for Transmissible Spongiform Encephalopathies

The three most stringent sterilization methods for heat-resistant instruments described in Annex III of the WHO guidelines are listed below; the methods are listed in order of more to less severe treatments.The article summarizing the findings of this experiment pdf icon[PDF - 211KB] by Brown et al. of the FDA was published in the Journal of Biomedical Materials Research (electronic version published October 2004).An experiment pdf icon[PDF - 88KB] conducted by Food and Drug Administration (FDA) investigators indicated that the use of appropriate containment pans and lids prevents escape of sodium hydroxide vapors that may cause damage to the autoclave (Brown and Merritt.[CDC NOTE: Sodium hypochlorite may be corrosive to some instruments.]

FDA investigators evaluated the effects to surgical instruments of the steps involved in the sterilization protocols listed above; some of the protocols they assessed subjected the instruments to harsher conditions than those prescribed above.[CDC NOTE: Sodium hypochlorite may be corrosive to some instruments.]

3- Immerse in 1N NaOH or sodium hypochlorite (20,000 ppm available chlorine) for 1 hour; remove and rinse in water, and then transfer to open pan and heat in a gravity displacement (121?C) or porous load (134?C) autoclave for 1 hour; clean; and subject to routine sterilization.