Week 4 Control of Microorganisms Flashcards
process to promote and establish conditions which minimize or eliminate biohazards
Reduction of a microbial population to a safe level by public health standards
sanitation
a process of completely removing or destroying all life forms and their products including endospores
sterilization
the destruction or inhibition of disease-causing microorganisms by chemical or physical means (applies only to inanimate objects and surfaces)
disinfection
the prevention or inhibiting of the growth of causative microorganisms (applies to living tissue)
antisepsis
manual process by which microorganisms are removed from a surface
scrubbing
a form of sterilization that reduces waste to a more manageable amount and form – ashes
incineration
a form of incineration for human remains
cremation
Temperature of approximately ____ must be maintained until remains have undergone complete combustion for cremation
1600°F
will sterilize water that does not contain endospores and kill vegetative bacteria, most viruses, and fungi
boiling
materials are incubated overnight to allow endospores to germinate then the objects are introduced to _____ the next day and this process is repeated
free-flowing steam
an autoclave machine is used to control microbial growth using ______
steam under pressure
____ temperatures do not always destroy vegetative microbes or endospores
____ temperatures do generally inhibit the growth of microbes but once temperature returns to ambient, the microbes will continue to function normally
cold
A form of nonionizing radiation that can control microorganism growth
-Organism must be exposed directly for it to be effective
-Some organisms are resistant to this method of control
ultraviolet light
a chemical or physical agent that destroys or inhibits disease-causing microorganisms
disinfectant
a substance that destroys microorganisms
germicide
an agent that destroys bacteria but not necessarily their spores
bactericide
a substance that kills fungi
fungicide
an agent destructive to viruses
virucide
Factors influencing disinfectant action (6)
nature and type of disinfectant, concentration of the disinfectant, type of material that is being disinfected, number and type of microbes present, length of exposure to the disinfectant, temperature and pH of the disinfectant during exposure
Physical methods of control of microorganisms (5)
scrubbing, dry heat, moist heat, cold, ultraviolet light
disinfect by oxidizing microbial cells; are generally very caustic and aggressive
halogens
chlorine-containing compounds
hypochlorites (bleaches)
compounds containing iodine which is often used as a preoperative skin disinfectant
iodophores
Control microbial growth by denaturing proteins and dissolving lipids
-Often added to other disinfectants to enhance germicidal power
-Do not kill endospores
alcohols
liquid formaldehyde solution
37% formaldehyde by mass, 40% formaldehyde by volume
formalin
Solution that is an effective disinfectant and a cold chemical sterilant when activated in 2% solution
-Germicidal in 10 minutes
-Kills endospores in 3–12 hours
-Can be used to sterilize embalming instruments and in situations where heat is not appropriate for the material being treated
glutaraldehyde
control microbes by denaturing proteins and disrupting cell membranes; generally not effective at killing endospores
phenolic compounds
slightly acidic, sweet odor, flammable
phenol (carbolic acid)
derived from toluene, common disinfectant
cresols (Lysol)
common embalming chemical ingredient + germicide
hexachlorophene
Disinfect by damaging cellular membranes and denaturing proteins
-Deactivated by soap
-Can lessen surface tension of cell membranes
-Include benzalkonium chloride, benzethoniumchloride, and cepacol
quaternary ammonium compounds
