Exam 3- UV and Handwashing Flashcards
what are the levels of decontamination
sterilization, disinfection, decontamination/sanitization, antisepsis/degermination
destroys and removes all viable microbes, including viruses and endospores
sterilization
sterilization is only used on what
inanimate objects
physical process or chemical agent that destroys vegetative pathogens, but not spores; also removes toxins
disinfection
disinfection is only used on what
inanimate objects
cleaning process that physically removes microbes and other debris from objects
decontamination/sanitization
decontamination/sanitization is used best on what
food and beverage
reduces the number of microbes on human skin; decontamination of living tissue
antisepsis/degermination
what is the most difficult microbe to kill
prions
what is the least difficult microbe to kill
enveloped viruses
what are the normal biota of human skin
M luteus, S epidermidis, S aureus, Cornyebacterium, and Propionibacterium acnes
normal bacteria on the hands are in constant competition with what
transient organisms
found on our skin, but do not normally grow there and are usually acquired through contact with a contaminated surface
transient organisms
at least 20-30 seconds to remove the emulsified skin oils
friction
soap is a what
surfactant
surfactants insert into the _____________ to disrupt it and create abnormal channels that alter permeability and cause leakage in and out of the cell
lipid bilayer
soaps or detergents emulsify __________- that have transient bacteria trapped in them
skin oils
what can surfactants do
bind to and emulsify skin oils allowing them to be scrubbed off while disrupting the cell membrane
what do surfactants limit
endospores and bacteria with waxy cell walls
what are the types of radiation that kill microbes
gamma and UV
is gamma ionizing or non ionizing
ionizing
is UV ionizing or non ionizing
non ionizing
kills microbes by creating free radicals within the cells
gamma radiation
kills microbes by damaging the DNA and creating dimers between adjacent thymine or cytosine in the DNA
UV radiation
what are UV limitations
cannot penetrate glass or plastic, can only be used on surfaces air and water, and not good for living tissue
what are the most difficult and least difficult microbes to kill (most difficult to least difficult)
prions
endospores
gram negative
gram positive