Ch. 23 Control of Microorganisms

What is sterilization in microbial control?

The highest level of microbial growth control, involving the complete removal or destruction of all life forms, including endospores and their products.

What is disinfection?

The destruction of pathogenic agents by chemical or physical means using disinfectants, which do not kill inactive microbial endospores but can kill most vegetative microorganisms.

What is antisepsis?

The control of microbial growth on living tissues to prevent infection, reducing microbial populations to levels determined by public health standards.

What are some physical methods of microbial control?

Scrubbing, temperature control, incineration (1600 °F - 1800 °F), and moist heat (steam).

What is UV radiation in microbial control?

A form of non-ionizing radiation used to control microbial growth.

What are the two categories of chemical antimicrobial agents?

1. Cidal agents that kill microorganisms. 2. Static agents that prevent growth but do not kill, including spores.

What factors influence the effectiveness of chemical agents?

Nature of disinfectant, concentration of disinfectant, length of exposure, temperature during exposure, nature of the material being disinfected, pH during exposure, and number of microorganisms present.

What are halogens and their role in disinfection?

Very strong disinfectants that work by oxidizing microorganisms, examples include chlorine and iodine.

What is formaldehyde used for in microbial control?

A concentrated solution (formalin) that controls the growth of microorganisms.

What is glutaraldehyde?

A chemical disinfectant that deactivates the DNA and RNA of microorganisms.

What is carbolic acid and its use?

Also known as phenol, it is used to produce disinfectants and has antiseptic properties.

What is hexachlorophene?

A primary antibacterial agent found in soaps, deodorants, and toothpastes, which is 450 times more effective than phenol as a germicide.

What are quaternary ammonium compounds?

Chemical agents that damage cellular membranes, with examples like benzalkonium chloride used on skin before surgery.

What is benzethonium chloride?

Another quaternary ammonium compound used in mouthwashes and throat lozenges.