Deck 4: Control of Microorganisms

Question 1

If this is present on a surface to be disinfected,it can shield microorganisms from the disinfectant or inactivate the disinfectant.What is this substance?

A) Bleach (sodium hypochlorite)
B) Organic material
C) Hydrochloric acid
D) Water

Answer 1

B
Bleach,hydrochloric acid,and water can counteract another disinfectant,but they cannot shield microorganisms from a disinfectant.Organic matter (e.g.,blood,pus)can keep the disinfectant from reaching and killing the microorganism.

Question 2

Organisms that are the most resistant to heat,chemicals,and radiation are:

A) Parasites
B) Prions
C) Bacteria
D) Viruses

Answer 2

B
Prions are naked pieces of protein,so they are harder to kill than any other organism.Viruses usually contain a nucleic acid,and all the mentioned forms of killing can effectively disrupt their nucleic acid.Bacteria and parasites are complete organisms that are killed by disinfection and sterilization,even in the spore and cyst stages.

Question 3

When eliminating organisms from inanimate objects,higher numbers of organisms require longer exposure times because:

A) All disinfecting agents are not alike and some require shorter times.
B) The chemical composition of the disinfecting agent varies.
C) Disinfecting agents containing carbon tetrachloride require longer times to act.
D) It takes longer to eliminate 99% of microorganisms.

Answer 3

D
When there are higher numbers of microorganisms,it takes longer to kill 99% of microorganisms present.Although disinfectants are different,it still takes longer to kill more organisms.The chemical composition of a disinfecting agent may affect the time required to kill microorganisms,but microbial load is a determining factor.

Question 4

A laboratory technician is working with tissue infected with Mycobacterium tuberculosis that has been preserved in formalin for a couple years.After dissecting the tissue,how should the worker sterilize the work area?

A) Wipe down the work area with a 37% formalin solution.
B) Wipe down the work area with a 10% bleach solution.
C) Wipe down the work area with a 50% alcohol solution.
D) Use formaldehyde gas to clean the area.

Question 5

For the most effective microbial killing,all iodophors must be properly diluted because:

A) They stain the skin if too concentrated.
B) This decreases contact time for adequate killing.
C) There must be enough free iodine to kill the microorganisms.
D) This increases contact time for adequate killing.

Question 6

Using two disinfectants to clean an area may actually do more harm than good.Why?

A) Two disinfectants may increase the amount of corrosion that occurs on a surface.
B) Two disinfectants may cause an adverse chemical reaction where a poisonous gas may be released.
C) When used together, two disinfectants may combine to sterilize a site instead of just disinfecting it.
D) Two disinfectants may inactivate one another's activity against microorganisms.

Question 7

When using disinfectants,it is important to follow the manufacturer's instructions for diluting the product because if it is not diluted properly:

A) There may not be enough free chemicals to kill the organisms.
B) You would be wasting money by using too much disinfectant.
C) The resulting solution would not kill mycobacteria.
D) The resulting solution would not kill parasites.

Question 8

When killing microorganisms,you must take all the following into consideration EXCEPT:

A) A type of microorganism
B) Temperature
C) Humidity
D) Bioburden

Question 9

Disinfectants are usually used at this temperature.

A) 50° to 100° C
B) 0° to 10° C
C) 25° to 50° C
D) 20° to 22° C

Question 10

The chemical or physical method that destroys all forms of life is called:

A) Sterilization
B) Disinfection
C) Bacteriostatic
D) Bactericidal

Question 11

Alcohols use this mechanism to inactivate microorganisms.

A) Denature proteins
B) Destroy DNA
C) Denature RNA
D) Inhibit cell wall synthesis

Question 12

Even though hypochlorites are inexpensive and have a broad range of microbes that they kill,they are not used as sterilants because of:

A) The corrosive nature of the compound
B) The activation required by organic matter
C) Short exposure time for sporicidal action
D) Long exposure time for sporicidal action

Question 13

The tech needs to sterilize a piece of equipment that cannot be autoclaved or gas sterilized because the equipment contains lenses,metal,and rubber components.What solution should be used to sterilize this piece of equipment?

A) 10% bleach
B) 37% formalin
C) Glutaraldehyde
D) 90% alcohol

Question 14

Chemosterilizers exert their killing effect through all the following mechanisms EXCEPT:

A) Denaturation of cellular proteins
B) Damage of RNA and DNA
C) Inactivating enzyme substrates
D) Reactions with components of the cytoplasmic membrane

Question 15

Autoclaves use this method to sterilize inanimate objects.

A) Dry heat
B) Heat under steam pressure
C) Microwaves
D) Infrared light rays

Question 16

After using the phone,the laboratory tech sprayed the receiver with a chemical spray.This process will kill a defined scope of microorganisms.What is this process called?

A) Sterilization
B) Bacteriostatic
C) Disinfection
D) Bactericidal

Question 17

Before performing a phlebotomy,the phlebotomist will clean the area on a patient's arm with a substance before inserting the needle.This substance is called a(n):

A) Disinfectant
B) Sterilizer
C) Antiseptic
D) Bactericidal

Question 18

Disinfectants containing heavy metal compounds have been replaced as disinfectants,except for _____,which is still used as a prophylactic treatment in newborns to prevent gonococcal conjunctivitis.

A) Silver nitrate
B) Copper sulfate
C) Ammonium nitrate
D) Mercuric chloride

Question 19

All the following factors play a significant role in the selection and implementation of the appropriate method of disinfection EXCEPT:

A) Temperature
B) Contact time
C) Biofilms
D) Humidity

Question 20

Pasteurization achieves _____.

A) Disinfection
B) Sterilization
C) Asepsis
D) Filtration

Question 21

This topical antiseptic disrupts the microbial cell membrane and precipitates the cellular contents.

A) Chlorhexidine gluconate
B) Povidone-iodine
C) 95% ethanol
D) 60% isopropyl alcohol

Question 22

The purpose of surgical hand scrubs and waterless hand rubs is to:

A) Eliminate the transient florae and most of the resident florae on the skin.
B) Remove all physical dirt and some residential florae.
C) Remove all resident florae.
D) Remove all transient florae.

Question 23

This organization regulates chemical skin antiseptics.

A) Environmental Protection Agency (EPA)
B) Food and Drug Administration (FDA)
C) Centers for Disease Control and Prevention (CDC)
D) National Institutes of Health (NIH)

Question 24

This compound is a diphenyl ether,and it exerts its bactericidal effects by disrupting the cell wall.It has good activity against gram-positive cocci,but poor activity against fungi.What is its name?

A) 95% ethanol
B) Triclosan
C) Chlorhexidine gluconate
D) Povidone iodine

Question 25

Why is laboratory-acquired infection an obvious hazard for personnel working in a microbiology lab?

A) Microbiology personnel do not always adhere to safety practices.
B) Safety practices are not applicable for the microbiology laboratory.
C) In-service education is not provided for microbiology staff.
D) Personnel deal with a variety of infections agents: viral, fungal, parasitic, and bacterial.

Question 26

The main goal of handwashing is to:

A) Sterilize a person's hand.
B) Increase the risk of passing on pathogens.
C) Eliminate transient florae.
D) Disinfect a person's hands.

Question 27

Routine handwashing in health care settings mandates washing at all the following times EXCEPT:

A) In high-risk areas such as ICU and burn units
B) On entering protective isolation units
C) Before and after routine patient contact
D) When gloves become soiled during a procedure or dressing change on the same patient.

Question 28

This chemical is a saturated 5-carbon dialdehyde that has broad-spectrum activity,rapid killing action,and remains active in the presence of organic matter.

A) Formalin
B) Formaldehyde
C) Haloaldehyde
D) Glutaraldehyde

Question 29

Many materials in hospitals that must be sterilized cannot withstand steam sterilization.Gas sterilization is used instead,using this gas.

A) Nitrous oxide
B) Oxygen
C) Ethylene oxide
D) Carbon dioxide

Question 30

Laboratory safety includes all the following areas EXCEPT:

A) Radioactivity
B) Chemical
C) Isolation
D) Fire

Question 31

The disinfectant label should indicate several highlighted points important in selecting the appropriate agents for designated use,including all the following EXCEPT:

A) Level of biocidal action
B) Alcohol content
C) The nature of microbial contamination
D) Structure and design of an item to be disinfected

Question 32

This agency regulates the use,sale,and distribution of antimicrobial pesticide products for certain inanimate,hard,nonporous surfaces,or incorporated into substances under the pesticide law.

A) Antimicrobial Division of Environmental Protection Agency (EPA)
B) Centers for Disease Control and Prevention (CDC)
C) U.S. Army Medical Research Institute for Infectious Diseases (USAMRIID)
D) U.S. Food and Drug Administration (FDA)

Question 33

The most common iodophor used in the United States for preoperative skin preparation is:

A) Calcium iodophor
B) 95% ethanol and iodine
C) Tincture of iodine
D) Povidone iodine

Question 34

These two alcohols are effective in killing hepatitis B virus (HBV).

A) 50% isopropyl and 50% butanol
B) 95% propanol and 70% ethanol
C) 70% isopropyl and 95% ethanol
D) 70% pentanol and 70% isopropyl

Question 35

These disinfectants are cationic,surface-activated agents that work by reducing the surface tension of molecules in a liquid,resulting in the disruption of the cellular membrane of microbes.

A) Quaternary ammonium compounds
B) Heavy metals
C) Chlorines
D) Iodophors

Question 36

High-level disinfectants are active against all the following EXCEPT:

A) Parasites
B) Spores
C) Fungi
D) Tubercle bacilli

Question 37

The most concentrated forms of ethanol and isopropyl alcohol are less bactericidal than the diluted forms of these alcohols.Why?

A) No free radicals are present in solution to kill the bacteria.
B) Only the dilutions can dissolve the lipopolysaccharide cell walls.
C) Proteins are not denatured readily in the absence of water.
D) Killing bacteria also requires the solution be heated, and it is difficult to heat concentrated alcohols because they are flammable.

Question 38

The comprehensive safety program for the microbiology laboratory needs to fulfill all the following provision EXCEPT:

A) It is specific to the hospital and does not need to conform to state, local, and federal regulations.
B) It must address biologic hazards.
C) It must teach correct techniques for lifting and moving heavy objects and patients (where applicable).
D) It must describe the safe handling, storage, and disposal of chemicals.

Question 39

Why should health care workers wash their hands after coming into contact with a patient?

A) To reduce the amount of red blood cells transmitted from one patient to the next
B) To reduce the occurrence of hemolytic transfusion reactions
C) To reduce the need for antiseptics and disinfectants
D) To reduce the spread of pathogenic bacteria from one individual to another

Question 40

The three types of alcohol used as an effective skin antiseptic include all the following EXCEPT:

A) 60% to 95% ethanol
B) Butyl alcohol
C) 50% to 91.3% isopropyl alcohol
D) n-Propyl alcohol

Question 41

All of the following organisms can typically cause infection from aerosolization of specimens EXCEPT:

A) Mycobacterium tuberculosis
B) Brucella spp.
C) Staphylococcus aureus
D) Francisella tularensis

Question 42

Work Practice Controls consist of all of the following EXCEPT:

A) Ensuring written procedures are in place for a task
B) Altering the manner in which a task is performed to reduce exposure to infectious agents
C) Allowing workers to eat at the bench if it gets busy and they don't have time to take a lunch break
D) Reviewing the procedure manual annually

Question 43

A Biosafety Level 1 (BSL-1)level of containment is used for organisms that:

A) Cause 90% mortality of infected people
B) Are well classified and not known to cause disease in healthy people
C) Cause 90% morbidity of infected people
D) Can be transmitted through aerosols

Question 44

A Material Safety Data Sheet (MSDS)contains all the following information EXCEPT:

A) The nature of a chemical (flammable, toxic, carcinogen)
B) General characteristics
C) Precautions when using a chemical
D) Classification of a chemical (acid, base, protein)

Question 45

The Biosafety Levels were categorized using all the following criteria EXCEPT:

A) The bacterial load necessary to cause infection
B) The organism's ability to cause serious illness
C) The organism's mode of transmission
D) Whether there is treatment available for an infection

Question 46

Engineering controls and work practice controls to ensure Standard Precautions are followed include all the following EXCEPT:

A) Eyewash stations
B) The use of safety needles
C) Plastic shield barriers
D) Fire blankets

Question 47

Because Biosafety Level 3 (BSL-3)organisms have the potential for aerosol transmission,and diseases with these agents may have serious lethal consequences,all of the following guidelines apply to BSL-3 labs EXCEPT:

A) BSL-3 labs should be separated from other parts of the building by an anteroom.
B) BSL-3 labs should have restricted access with logbook documentation of personnel entering and exiting lab.
C) BSL-3 labs should have solid ceiling and floor seams, and any seams must be sealed.
D) BSL-3 labs should have positive air pressure.

Question 48

The Occupational Safety and Health Administration (OSHA)requires laboratories to have this document to ensure that laboratory personnel have a thorough working knowledge of the hazards of the chemicals with which they work.

A) Chemical Control Plan
B) Standard Operating Procedures
C) Chemical Hygiene Plan
D) OSHA Compliance Plan

Question 49

Standard Precautions do not address the following:

A) Handwashing
B) Gloves
C) Lab coats
D) Respirators

Question 50

A Biosafety Level 2 (BSL-2)level of containment is used for organisms that:

A) Can cause a catastrophe if released
B) Usually cause 90% mortality in the population
C) Create a moderate potential hazard for employees and the environment
D) Do not cause significant harm to employees and the environment

Question 51

If a laboratory uses hazardous chemicals,it must:

A) Keep a chemical inventory and Material Safety Data Sheets (MSDSs) on hand.
B) Keep chemicals in a special corrosive cabinet.
C) Keep chemicals in a special locking cabinet.
D) Post chemical names and locations on the door of the laboratory.

Question 52

The Clinical Laboratory Standards Institute (CLSI)defines hazardous waste as:

A) Those wastes that present an aerosol, infectious, or sharps danger to laboratory and hospital personnel
B) Those substances that singly or in combination pose a significant present or potential threat or hazard to human health
C) Exotic and indigenous microorganisms and chemicals that present an infectious, explosive, corrosive, or irritant risk
D) All the following classes of substances: microorganisms, toxic chemicals, electricity, fire, and blood-borne pathogens

Question 53

The most common route of infection of laboratory workers with hepatitis B virus (HBV)and human immunodeficiency virus (HIV)is:

A) Mucous membranes
B) Inhalation
C) Ingestion
D) Needlestick

Question 54

Processing of patient specimens and handling of actively growing cultures of microorganisms puts an employee at risk of potential contact with the infectious agent through all the following routes EXCEPT:

A) Mucous membranes
B) Blood splashed onto intact skin
C) Inhalation of aerosols
D) Accidental ingestion

Question 55

Technicians are doing the morning chemistry run.Once they load the specimens onto the instrument,they remove their gloves to do paperwork in a clean area of the laboratory.What should the technicians do after removing their gloves?

A) Reposition the tubes in the racks.
B) Take a break and eat a snack.
C) Call any critical values.
D) Wash their hands.

Question 56

All of the following are examples of personal protective equipment (PPE)EXCEPT:

A) Gloves
B) Lab coats
C) Safety glasses
D) Prescription glasses

Question 57

The laboratory exposure control plan should contain all the following EXCEPT:

A) Engineer and work practice controls
B) Review of control plan every 5 years
C) Methods of compliance for Standard Precautions
D) Guidelines for handling and disposal of regulated waste

Question 58

What protective measures can a laboratory worker take when working with actively growing cultures to ensure that they do not become infected?

A) Ensure that fungal cultures are sealed and worked in a biosafety cabinet.
B) Wash their hands at the end of their shift.
C) Handle specimens routinely, using extra care for HIV and HBV cultures.
D) Take off bandages on fingers when reading plates.

Question 59

Biosafety Level 4 (BSL-4)organisms are dangerous,exotic,and pose an increased risk of aerosol-transmitted infections and life-threatening disease.Two examples of BSL-4 organisms are:

A) Smallpox and Ebola
B) St. Louis encephalitis virus and Coccidioides immitis
C) Mycobacterium tuberculosis and Ebola
D) Francisella tularensis and Ebola

Question 60

Universal/Standard Precautions require that:

A) Only some body fluids be considered infectious and capable of transmitting disease
B) Body fluids with visible blood be treated as noninfectious
C) Blood and body fluids from all patients be considered infectious and capable of transmitting disease
D) Urine and feces be considered noninfectious

Question 61

Laboratory Safety for Hazardous Chemicals includes:

A) Restricting use of these chemicals to specific individuals
B) Using fume hoods to prevent inhalation of fumes
C) Locking chemicals in one specific "corrosives" cabinet
D) Providing biohazard training to affected individuals

Question 62

Three levels of laboratories outlined in the Laboratory Response Network (LRN)include all the following EXCEPT:

A) Sentinel
B) Reference
C) First responder
D) National responder

Question 63

In the Laboratory Response Network (LRN)program,hospital-based microbiology laboratories are classified as this type of laboratory.

A) Reference
B) National
C) Primary
D) Sentinel

Question 64

Most institutions use the RACE acronym to respond to a fire emergency.RACE stands for

A) Race, Alert, Cite, Evacuate
B) Run, Avoid, Call, Emergency
C) Rescue, Alarm, Contain, Extinguish
D) Retrieve, Announce, Close, Exit

Question 65

Once bioterrorism is suspected,a sentinel laboratory should perform all culture manipulation using these safety guidelines.

A) BSL-2
B) BSL-3
C) BSL-4
D) BSL-1

Question 66

The Joint Commission on Accreditation of Healthcare Organizations (JCAHO)requires the following safety training to be documented in an employee's record EXCEPT:

A) Proper storage of gases
B) Biosafety level training
C) Blood-borne pathogen training
D) Hazardous materials management

Question 67

To ensure the electrical safety of laboratory personnel,the College of American Pathologists (CAP)requires these checks annually.

A) Leakage and AC check
B) Electrical cords and cycle check
C) Grounding and cycle check
D) Electrical grounding and leakage checks

Question 68

Category A bioterrorism agents:

A) Pose the highest threat because they are easily transmitted and highly infectious
B) Have moderate morbidity and low mortality and are not easily transmitted
C) Are emerging pathogens
D) Are enteric pathogens

Question 69

The best way to care for your back is to prevent back injuries.All of the following are some ways to prevent back injuries EXCEPT:

A) Carefully lifting heavy objects overhead
B) Using good posture
C) Using the legs to lift, not the back
D) Asking for assistance when a load is too heavy