Evaluation of a Steam Autoclave for Sterilizing Medical Waste at a University Health Center

Evaluation of a Steam Autoclave for Sterilizing Medical Waste at a University Health Center Page E9 T. Tiller*, A. Linscott Close Close preview | Purchase PDF (56 K) | Related articles | Related reference work articles AbstractAbstract Abstract BACKGROUND: As healthcare institutions search for methods to decrease costs associated with medical waste disposal, many are turning to the use of steam autoclaves. Steam autoclaving theoretically saves money by sterilizing large loads of medical waste, making it safe for disposal in a public landfill. There are no national standards for challenging medical waste autoclaves and no guidelines for parameters of sterilization for medical waste. When Louisiana State University Health Sciences Center—Shreveport (LSUHSC—S) tested one steam autoclave marketed as a medical waste autoclave, the machine repeatedly failed the tests. A complete description of the challenge testing and results are presented. METHODS: A test scenario was developed using biological indicators (BI) and chemical indicators distributed throughout four loads of clean waste which were controlled for weight, volume, and density. BI ampules and chemical strips were wrapped inside an adult diaper, which was tied in a common plastic bag and placed inside an open medical waste bag, reflecting common diaper disposal methods. At least five prepared bags were distributed throughout each load. Loads were run at 270° F, 30 pounds per square inch (psi), for 30 minutes, or at 270° F, 30 psi, for 60 minutes. RESULTS: Bacterial growth occurred in 18 out of 22 ampules, and chemical indicators failed in 19 out of 22 locations. CONCLUSIONS: Steam did not fully penetrate the load, and bacteria were not killed. Despite assurances from marketers of medical waste autoclaves, institutions considering this method must test autoclaves carefully to ensure safety and compliance with local health regulations.