Biosafety Manual

46 Biosafety Manual ¤ Quats are easily inactivated by organic materials, anionic detergents (soaps), or salts of metals found in hard water. Inactivation, Verification, and Biocontainment of Infectious Agents and Toxins For more information on procedures for inactivation and safe containment of toxins please refer to the Procedures for the Inactivation and Safe Containment of Toxins documen t which was adapted from a presentation by Dr. Robert W. Wannemacher from the U.S. Army Medical Research Institute of Infectious Disease. Refer also to the BMBL - Section VIII-G, “Toxin Agents,” the BMBL -Appendix I, “Guidelines for Work with Toxins of Biological Origin,” and the BMBL - Appendix K, “Inactivation and Verification.” Prion Inactivation and Biocontainment Procedures USDA Recommendations for Inactivation of Prions Affecting Livestock • Porous load autoclaving at 134°C-138°C at 30 psi for 18 minutes holding time at temperature (does not include warm- up and cool-down). (Please note that this practice is consistent with USDA requirements for prions affecting animals, but not BMBL recommendations for prions affecting humans.) • Soak ground samples in 40% household bleach (5.25% sodium hypochlorite) to provide 20,000 ppm available chlorine (prepared freshly at time of use). Soak for minimum of 1 hour at 20°C. • Non-disposable instruments should be soaked in 40% household bleach for 1 hour, then rinsed with water and autoclaved at 134°C for 1 hour. • Wash all surfaces with sodium hypochlorite (20,000 ppm), soaking for 60 minutes, then rinse with water. Note: Some surfaces are prone to corrosion from prolonged exposure to these chemicals, so rinsing is very important. BMBL Recommendations for Inactivation of Prions Affecting Humans • Autoclave at 134°C for 18 minutes (does not include warm-up and cool-down). • After disinfection waste must be incinerated or land filled. • 1N sodium hydroxide or sodium hypochlorite (20,000 ppm),