Related Experiment Video
Updated: Jul 13, 2026

Remote Laboratory Management: Respiratory Virus Diagnostics
Published on: April 6, 2019
Treatment of discarded blood units: disinfection with hypochlorite / formalin versus steam sterilization
V Chitnis1, S Chitnis, S Patil
1Department of Microbiology, Choithram Hospital and Research Centre, Indore - 452 001, India.
Abstract:
Blood bank regulations and bio medical waste rules of India advocate disinfection of contaminated blood units. Incineration is not recommended due to poly-vinyl chloride (PVC) content of blood bags. This study was designed to evaluate the efficacy of chemical disinfection of blood units deliberately contaminated with Staphylococcus aureus and E. coli with 1 and 6 % hypochlorite, 10% formalin and 33% formaldehyde and autoclaving of blood units contaminated with the above mentioned vegetative forms and B. stearothermophilus spores. Only 33 % formaldehyde could bring about 5 log reduction of bacteria but it is highly irritating and toxic. Autoclaving at 15 lbs pressure for 2 hours uniformly inactivated the vegetative forms and B. stearothermophilus spores. Thus, autoclaving of PVC blood bags is a safer and reliable method compared to chemical disinfection.
Related Concept Videos
Methods of Sterilization I: Physical Methods
Steam sterilization uses non-toxic, low-cost moist heat in the form of saturated steam under pressure, which is fast, microbicidal, and sporicidal, and quickly warms and penetrates fabrics. Autoclaves, or steam sterilizers, expose each item to direct steam contact for a predetermined time at the necessary...
Methods of Sterilization II: Chemical Methods
Using chemical sterilization rather than heat to clean out equipment is recommended. It eradicates and removes all bacteria,...
Cleaning, Sterilization, and Disinfection
Cleaning
The cleaning process usually involves using water with detergents or enzymatic cleaner and removing foreign material from objects and surfaces, including organic material such as body fluids or inorganic material like soil. Cleaning is performed before high-level disinfection and sterilization because foreign materials on the cover of the devices interfere with process...
Physical Methods for Controlling Microbial Growth: Temperature
Hand hygiene
Hand washing...
Chemical Agents for Microbial Control

