Safe Management of Wastes from Healthcare Activities
2nd. Edition by World Health Organisation
Treatment and disposal methods
The purpose of treatment is to reduce the potential hazard posed by health- care waste, while endeavoring to protect the environment. Measures should first be followed to minimize and reuse waste items where it is safe to do so. Where this is not possible the unusable waste materials should preferably be treated to reduce their potential hazard to health and environmental hazard and volume, with the remaining residues sent for land disposal to suitably constructed site.
Selection of treatment methods some of the factors to consider include:
Chemical treatment and shredding technology
Chemical treatment methods use disinfectants such as paracetic acid. Chemical processes often involve shredding, grinding or mixing to increase exposure of the waste to the chemical agent. The largest proportion of hazardous health-care waste generated is potentially infectious. The most established waste -management technologies focus on disinfection.
Disinfection can be defined as the reduction or removal of disease -causing microorganisms (pathogens) to minimize the potential for disease transmission. Since the complete destruction of all microorganisms is difficult to establish. the STAATT classification system to denote levels of “microbial inactivation“ was established to define measures of performance of health-care waste treatment technologies.
A common microbial inactivation standard for health-care waste treatment based on the staatt critera is level iii.
The aim of disinfection is to eliminate microorganisms or at least reduce their numbers to an acceptable level. Shredding of solid healthcare waste before or during disinfection should be done in a closed system to avoid the release of pathogens into the air.
Internal shredding is essential for the following reasons:
- • to increase the surface area of contact between waste and disinfectant, eliminating voids in the waste load
- • to render any anatomical parts unrecognizable to avoid adverse visual impact on disposal
- • to reduce the volume of waste