Treatment and Disposal of Health Care Wastes Flashcards
Treatment and Disposal of HCW
Thermal decomposition of healthcare wastes in the **absence of supplied molecular oxygen ** In the destruction chamber in which the said HCW is converted into gaseous, liquid, or solid form.
It can handle the full range of healthcare wastes. Waste residues may be in form of greasy aggregates or slugs, recoverable metals, or carbon black. These residues are disposed of in a landfill.
Pyrolysis
Uses steam sterilization to render waste harmless and is an efficient wet thermal disinfection process. This method of using pressure and heat is widely used and usual setting is at 121°C with a pressure of 15 psi for 15-30 minutes. Indicators such as color-changing tapes or biological test ampules containing bacterial spores can be used to check the validity of the sterilization.
Autoclave
incorporates some type of size reduction device. Shredding of wastes is done before disinfection.
In this process, waste is exposed to microwaves that raise the temperature to 100 °C (237.6 °F) for at least 30 minutes.
Microorganisms are destroyed by moist heat which irreversibly coagulates and denatures enzymes and structural proteins.
Microwave
Chemicals like sodium hypochlorite, hydrogen peroxide, **peroxyacetic acid **and **heated alkali **are added to healthcare wastes to kill or inactivate pathogens present. It is recommended that sodium hypochlorite (bleach) with a concentration of 5% be used for chemical disinfection.
Chemical Disinfection.
The process uses an enzyme mixture to decontaminate healthcare wastes.
The resulting by-product is put through an extruder to remove water for wastewater disposal. The technology is suited for large applications and is also being developed for possible use in the agricultural sector.
Biological Processes.
This involves the filling of containers with waste, adding and
immobilizing material, and sealing the containers. The process uses either cubic boxes made of high-density polyethylene or metallic drums, that are three- quarters filled with sharps or chemical or pharmaceutical residues.
The containers or boxes are then filled up with a medium such as plastic foam, bituminous sand and cement mortar. After the medium has dried, the containers are sealed and disposed of in landfill.
Encapsulation
Especially suitable for pharmaceutical waste is the *process of inertization that involves the mixing of the waste with cement and other substances before disposal. *
For the inertization of pharmaceutical waste, the packaging shall be removed, the pharmaceuticals ground, and a mixture of water, lime and cement added. The homogenous mass produced can be transported to a suitable storage site.
Alternatively, the homogeneous mixture can
be transported in liquid state to a landfill and poured into municipal waste. The process is relatively inexpensive and can be performed using relatively unsophisticated equipment.
Inertization
Remember!
- Health care workers should segregate waste
at point of generation. - Waste should NEVER be re-sorted.
- Seal all waste containers and label them to
describe contents.
HCW Management Best practices
- Highly infectious waste must be disinfected at source.
- Anatomical waste including recognizable body parts, placenta waste and fetus should be disposed of through safe burial or cremation.
- Pathological waste must be refrigerated if not collected or treated within 24 hours.
- Sharps waste must be shredded or crushed befor transport to landfill.
- Chemical and pharmaceutical wastes shall be segregated and collected separately.
- The radioactive waste has to be decayed to background radiation levels. If it has reached the background radiation level and is not mixed with infectious or chemical waste, then radioactive waste is considered as regular non infectious waste.
- All waste bins must be properly covered to prevent cross contamination.
- Aerosol containers can be collected with the general waste
