Microbial Control CH 9 part1 EXAM2

Flashcards on microbial control methods, including sterilization, disinfection, and germicides.

What is sterilization

Destruction or removal of ALL viable microorganisms, including endospores and viruses.

Disinfection

Destruction or removal of vegetative pathogens but not endospores.

Sanitization

Mechanical removal of most microbes to reduce contamination to safe levels.

Antisepsis

Destruction or removal of vegetative pathogens on the human skin.

Most resistant microbe to control methods

Endospores

Least resistant microbe to control methods

Viruses

Rank microbes from most to least resistant to control methods

Endospores > Mycobacterium > Protozoa > Gram-negative bacteria > Fungi > Gram-positive

bacteria > Viruses

What are the two broad approaches to microbial control

Physical control and Chemical control.

How chemical agents affect the cell wall

Block synthesis or digest the wall.

What are examples of agents that disrupt the cytoplasmic membrane

Detergents and alcohol.

What does moist heat include

Pasteurization, boiling water, and steam (e.g., autoclave).

Autoclave

Sterilization using steam under pressure (121°C at 15 psi).

Which type of radiation achieves sterilization

Ionizing radiation (gamma rays, X-rays).

Does nonionizing UV radiation sterilize?

No, it only slightly penetrates and causes DNA damage.

Does liquid filtration sterilize?

Yes, it can sterilize heat-sensitive materials.

Does air filtration sterilize?

No, HEPA filters only remove particles.

How osmotic pressure controls microbes

High salt/sugar creates hypertonic environment causing plasmolysis.

Name some high-level germicides

Hydrogen peroxide vapor, glutaraldehyde, ethylene oxide, plasma, supercritical CO2, bleach.

Name some intermediate-level germicides

Phenol, chlorhexidine, alcohol.

Name some low-level germicides

Heavy metals (e.g., silver nitrate), quats.

What are critical medical equipment

Items that enter sterile tissue or the vascular system and must be sterile.

What is semi-critical equipment?

Items that contact mucous membranes and require high-level disinfection.

What is non-critical equipment?

Items that contact intact skin and require intermediate to low-level disinfection.