Disinfection Flashcards
(83 cards)
UV light for decontaminating. What wavelength?
254 nm
Abbreviation SAL regarding disinfection
Sterility Assurance Level
Decontamination is defined by CDC as:
Reduces the level of microbial contamination so that infection transmission is eliminated.
The amount of paraformaldehyde flakes that is typically used to generate the required amount of formaldehyde gas for area or BSC decontamination is:
0.3 g/cu. ft.
The microorganism that is considered least resistant to inactivation by chemical or physical means would be:
Lipid or medium sized viruses
According to Spaulding’s classification of device surfaces, semi-critical medical devices come into contact with mucous membranes and require what level of disinfection prior to reuse?
High
The generally accepted level for an SAL is:
1: 1,000,000
An Fo is the equivalent exposure time at what temperature?
121 degrees C
Which level of chlorine is considered appropriate by CDC and WHO for most intermediate level disinfection?
500-1000 ppm
When choosing a uv meter for measuring uv light used for disinfection, it is most important that:
a. It is battery operated
b. Gives readings in microwatts/cm2 with peak response at 254 nm
c. Deducts background radiation level
d. Is hand held
e. Gives readings in microwatts/cm2 with peak response at 298 nm
b. Gives readings in microwatts/cm2 with peak response at 254 nm
Which organism is used as a biological indicator to test gamma radiation sterilization processes?
a. Geobacillus stearothermophilus
b. Bacillus megaterium
c. Bacillus pumulis
d. Bacillus radiothermans
e. Bacillus atrophaeus
c. Bacillus pumulis
Sterilization is described as the elimination of all viable microorganism; disinfection generally refers to:
a. The elimination of all pathogens
b. The elimination of bacteria and Mycobacterium tuberculosis
c. The reduction of organisms to an acceptable level
d. The elimination of vegetative bacteria and viruses
c. The reduction of organisms to an acceptable level
The term “D-value” used in reference to sterilization refers to:
a. The time needed to reduce the concentration of a given organism by 90%
b. The number of degrees above 121o C that is required to kill off 106 organisms
c. The number of degrees above 100 o C that is required to kill off 106 organisms
d. The time needed to reduce the concentration of a given organism by 50%
e. The level of destructiveness of an autoclave cycle as measured by thermocouples
a. The time needed to reduce the concentration of a given organism by 90%
Which of the following sterilization methods would not be effective for equipment or materials that are placed inside of a paper wrap?
a. EtO
b. Vaporized H2O2
c. Gamma sterilization
d. UV light
e. Steam autoclave
d. UV light
Which of the following disinfectants is not considered toxic?
a. Isopropyl alcohol
b. Quaternary ammonium compounds
c. Chlorine compounds
d. Hydrogen peroxide
e. Depending on the level, all of the above could be considered toxic.
e. Depending on the level, all of the above could be considered toxic.
The sterilization method of choice for a reusable piece of equipment that is basically polyethylene with pvc tubing, natural rubber gaskets, and nylon tabs, would be:
a. Steam at 121oC
b. Vaporized H2O2
c. Ethylene Oxide
d. Dry heat
c. Ethylene Oxide
Rank the following in order of their resistance to physical and chemical treatments, with 1 meaning most resistant and 7 meaning least resistant: \_\_ fungi \_\_ vegetative bacteria \_\_ lipid viruses \_\_ non-lipid viruses \_\_ bacterial spores \_\_ prions \_\_ mycobacteria
(5,6,7,4,2,1,3)
__ prions
__ bacterial spores (anthrax, clostridium)
__ mycobacteria (TB)
__ non-lipid or small viruses (polio virus, coxsackievirus, rhinovirus, HAV)
__ fungi
__ vegetative bacteria
__ lipid viruses (Herpes simplex, CMV, RSV, HBV, HCV, HIV, hantavirus, ebola virus)
Higher concentrations of an active ingredient in a disinfectant may not always relate to a higher microbicidal activity. That is known to be true about the following material:
a. chlorine bleach solution
b. ethanol
c. glutaraldehyde
d. phenol
b. ethanol
A disinfectant classified as a “hospital disinfectant” by the EPA generally falls into the following ranking system that is commonly used by CDC:
a. High level disinfectant
b. Moderate level disinfectant
c. Low level disinfectant
d. Low or moderate level disinfectant, depending on formulation
e. Moderate or high level disinfectant, depending on formulation
d. Low or moderate level disinfectant, depending on formulation
Sterilization
destroys all microbial life, including high numbers of bacterial spores
Disinfection
eliminates nearly all recognized pathogens, disease causing organisms, but generally not spores, on inanimate surfaces
Antisepsis
reduction of organisms on living
tissues
Biocide
kills type of organism or
group, e.g., tuberculocide, virucide,
sporocide, etc.
Biostat .
prevents organisms or group
from growing, e.g., bacteriostat,
fungistat, etc
