[august 2025 mtle] microbiology quality control

daily

temperature checks in the laboratory need to be done _____ on all temperature-dependent equipment

incubator

autoclave

heating blocks

water bath

refrigerators

freezers

these are examples of temperature-dependent equipment

temperature

CO2

what are the parameters being tested in an incubator?

daily

every when are incubators tested for QC?

anaerobiosis

what are the parameters being tested for QC for a gaspak jar?

each use

every when are gaspak jars tested for QC?

anaerobiosis

temperature

humidity

what are the parameters being tested for QC in an anaerobe chamber?

daily

every when are anaerobe chambers being tested for QC?

air flow

what is the parameter being tested for QC in a biosafety cabinet?

specialist

who performs the QC for air flow in a BSC?

annually

any time hoods are moved

frequency of QC for a BSC?

RPM

what is being checked in a centrifuge when conducting QC?

every 6 months

what is the frequency of QC for a centrifuge?

cleanliness

adjusted

what is being checked in a microscope when conducting QC?

four times per year/quarterly

as needed

what is the frequency of QC of a microscope?

temperature

spore testing

what is being checked in a autoclave when conducting QC?

daily

each load

temperature of an autoclave should be checked when?

weekly

spore testing of an autoclave should be done when?

accuracy of weights

what is being checked in balance when conducting QC?

annually

what is the frequency of QC of balance?

before use

all user-prepared culture media should be tested when?

organisms expected to grow and not grow

each user-prepared media should be tested with both?

sterility

pH

medium should also be tested for?

most

organisms for QC should represent the most or least fastidious?

dilute

primary plating should be tested with ____ suspensions of specimens

undiluted

biochemical media can be tested with _____ media

2 years

QC records for user-prepared media must be maintained for _____

manufacturer

commercially prepared media are usually tested by who?

chocolate agar

selective media for Neisseria and Campylobacter

which certain types of commercially-prepared media should be retested by the user?

moisture

sterility

breakage

appearance

the laboratory must examine commercially-prepared media for the ff parameters?

each day of use

reagents must be tested when?

positive control

negative control

reagents must be tested each day of use with which controls?

daily

QC should be performed and documented on all staining procedures at least?

Staphylococcus aureus ATCC 25923

Escherichia coli ATCC 25922

for gram stain, these are the biochemical QC organisms used

1 year

non-fastidious, aerobic bacterial organisms can be saved up to ______

Trypticase soy agar slants

non-fastidious, aerobic bacterial organisms can be saved up to 1 year in which medium?

lyophilization (freeze-drying)

freezing at -70 deg. Celsius

long-term storage of less than 1 year or aerobes and anaerobes can be accomplished either by which methods?

5 years

frozen, non-fastidious organisms should be thawed, re-isolated and refrozen every _____?

3 years

frozen, fastidious organisms should be thawed, re-isolated and refrozen every ______?

10% skim milk

TSB with 15% glycerol

10% horse blood in sterile, screw-cap vials

stock isolates may be maintained by freezing them in?

yeasts

_____ can be treated as non-fastidious bacterial organisms for maintaining stock cultures

molds

_____ can be stored on potato dextrose agar slants at 4 degrees C for 6 months

potato dextrose agar slants

molds can be stored on which media?

4 degrees Celsius

molds can be stored on PDA slants at what temperature?

6 months to 1 year

molds can be stored on PDA slants in the fridge for up to?

mineral oil

for longer-term storage, molds on PDA slants may be over laid with sterile _____

room temperature

for longer-term storage, molds on PDA slants may be over laid with sterile mineral oil and stored at?

Lowenstein-Jenson agar slant

acid-fast bacilli may be kept on which culture media?

4 degrees Celsius

acid-fast bacilli may be kept on LJ agar slants at which temperature?

1 year

acid-fast bacilli may be kept on LJ agar slants at 4 deg. C for up to?

-70 deg. Celsius

acid-fast bacilli may also be frozen at what temperature?

7H9 broth with glycerol

acid-fast bacilli may also be frozen at -70 deg. C in what culture media?

-70 degrees Celsius

viruses may be stored at which temperature?

indefinitely

viruses may be stored in -70 degrees C until?

10% dimethyl sulfoxide

fetal bovine serum

viruses may be stored indefinitely at -70 degrees C with a cryoprotectant such as ______ or ______?

Permount

clinical parasitology slides may be preserved indefinitely by adding a drop of _____ and a coverslip.

periodically

clinical parasitology slides prepared in-house should be inspected _____, because the preservation solution may deteriorate and crack over time.

test verification

establishes that the performance parameters of the test are satisfactory

test verification

usually performed when a new method or test is introduced

test verification

results indicate that the test is acceptable for routine use

test verification

results indicate that further verification studies are required

test verification

results indicated that the test is unsuitable for routine use until its performance parameters are verified

test validation

ongoing process that provides information that a test is performing correctly

test validation

components include QC, PT, verification of employee competency and instrument calibration

test validation

results indicate that test continues to be acceptible

test validation

results indicate that further investigation is warranted

test validation

results indicate that immediate corrective action must be undertaken, and the test must be considered unsuitable for routine use until it can be validated