Treatment of infectious waste: development and testing of an add-on set for used gravity displacement autoclaves

The safe management of potentially infectious healthcare waste is gaining increasing worldwide importance. In developing countries, simple incinerators are used for the treatment of this type of waste stream. However, as these incinerators produce high emissions and represent the main generators of dioxin and furans in these countries, alternative and cost-effective solutions are needed. As steam treatment systems do not produce persistent organic pollutants, the use of existing (older) medical autoclaves could represent a solution for the treatment of infectious waste. ETLog Health EnviroTech & Logistics, the German-based consulting and engineering company carried out the first research into whether gravity air displacement autoclaves can be used for the safe decontamination of infectious waste. The research showed that it is not possible to decontaminate waste using this type of autoclave. A subsequent research and development phase might, however, make it possible to develop a new process cycle. Tests carried out on the basis of international standards and norms showed that by applying this process cycle and using an add-on set, it is possible to treat healthcare waste using the existing stock of older medical autoclaves. The process cycle and the add-on set developed were tested under existing conditions in Hanoi, Vietnam using the treatment cycle developed for a 13-year-old autoclave. All the parameters for infectious waste decontamination were reached. As modified autoclaves prevent the emission of toxic substances, this approach presents an interim solution, which avoids the impacts on human health and the environment caused by the incineration of healthcare waste.