Mechanical method of sterilization involves physically removing microorganisms rather than killing them.
It is typically a pre-step to sterilization processes.
A) Scrubbing and Washing
Principle:
Uses mechanical action and detergents to physically remove microorganisms and organic matter, reducing microbial load.
Procedure:
Preparation: Wear PPE and use appropriate cleaning agents.
Cleaning Process:
Soaking: Soak items in warm, soapy water to loosen debris.
Scrubbing: Manually scrub surfaces and crevices with brushes.
Rinsing: Rinse thoroughly to remove all residues.
Drying: Ensure items are dried to prevent further microbial growth.
Disinfection (Optional): Immerse items in a chemical disinfectant if immediate sterilization is not possible.
Merits:
Essential for removing debris that may shield microbes during sterilization.
Cost-effective with minimal equipment required.
Demerits:
Labor-intensive and time-consuming.
Only reduces microbial load, not a complete sterilization method.
Applications:
Pre-sterilization cleaning of surgical instruments.
General hygiene in healthcare and food preparation areas.
B) Ultrasonic Cleaning
Principle:
High-frequency sound waves (20-40 kHz) create cavitation bubbles in a liquid, which dislodge particles and microorganisms from surfaces.
Procedure:
Preparation: Fill the tank with cleaning solution and degas it by running the machine empty.
Loading: Submerge items in a tray, ensuring no contact between them or the tank bottom.
Cleaning Cycle: Set temperature (40°C-60°C) and time (5-10 minutes) before starting the cycle.
Post-Cleaning: Rinse and dry items thoroughly.
Merits:
Reaches inaccessible areas and is gentle on delicate instruments.
Demerits:
Not a sterilization method; further processing is needed.
Equipment investment required.
Applications of Mechanical method of sterilization:
Cleaning of dental, surgical, and laboratory instruments.
Maintenance of precision mechanical and electronic parts.