Deck 4: Control of Microorganisms

Question 1

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

Answer 1

C
Disinfection kills a defined scope of microorganisms.Sterilization kills all organisms and spores at a site.Bacteriostatic and bactericidal are adjectives that describe the particular action of chemical agents: to inhibit bacterial growth or kill bacteria.

Question 2

What two alcohols are effective in killing the 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

Answer 2

C
The only two alcohols used in U.S.hospitals that kill HBV are 70% isopropyl and 95% ethanol.

Question 3

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

Answer 3

C
Glutaraldehyde is the sterilant of choice, because it is not inactivated by organic material, and it can kill both microbes and spores, depending on contact time.Ten percent bleach cannot be used because it is a corrosive and can corrode metal; 37% formalin cannot be used because it is a carcinogen, and the Occupational Safety and Health Administration (OSHA) does not recommend it for routine sterilizing or disinfecting; 90% alcohol can be corrosive, but it is also inactivated with any organic material that may be present on the instrument.

Question 4

Disinfectants are usually used at temperatures of:

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

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

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 7

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

A)parasites.
B)prions.
C)bacteria.
D)viruses.

Question 8

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

A)sterilization.
B)disinfection.
C)bacteriostatic.
D)bactericidal.

Question 9

Pasteurization achieves:

A)disinfection.
B)sterilization.
C)asepsis.
D)filtration.

Question 10

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.

Question 11

Many materials in hospitals that must be sterilized cannot withstand steam sterilization.Gas sterilization is used instead, which uses:

A)nitrous oxide.
B)oxygen.
C)ethylene oxide.
D)carbon dioxide.

Question 12

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 13

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

Question 14

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 15

Alcohols use what mechanism to inactivate microorganisms?

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

Question 16

Which 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 17

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

A)parasites.
B)spores.
C)fungi.
D)tubercle bacilli.

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

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

A)corrosive nature of the compound.
B)activation required by organic matter.
C)short exposure time for sporicidal action.
D)long exposure time for sporicidal action.

Question 20

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 21

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

A)eliminate the transient flora and most of the resident flora on the skin.
B)remove all physical dirt and some residential flora.
C)remove all resident flora.
D)remove all transient flora.

Question 22

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 23

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 24

Which 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 25

Standard Precautions do not address which of the following?

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

Question 26

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 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 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 29

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 30

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 31

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

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

Question 32

The main goal of handwashing is to:

A)sterilize a person's hand.
B)increase the risk of passing on pathogens.
C)eliminate transient flora.
D)disinfect a person's hands.

Question 33

Laboratory safety includes all the following areas except:

A)radioactivity.
B)chemical.
C)isolation.
D)fire.

Question 34

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

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 infectious agents: viral, fungal, parasitic, and bacterial.

Question 35

What 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

Which 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 37

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 38

Which 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 39

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 40

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 41

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 42

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 43

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

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

Question 44

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 45

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 46

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 47

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 bloodborne pathogens.

Question 48

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.

Question 49

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

A)the nature of a chemical (flammable, toxic, carcinogenic).
B)general characteristics.
C)precautions when using a chemical.
D)classification of a chemical (acid, base, protein).

Question 50

In the LRN program, hospital-based microbiology laboratories are classified as which type of laboratory?

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

Question 51

OSHA requires laboratories to have what 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 52

Safety program and 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 do not have time to take a lunch break.
D)reviewing the procedure manual annually.

Question 53

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 54

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

A)gloves.
B)laboratory coats.
C)safety glasses.
D)prescription glasses.

Question 55

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)Marburg and Congo-Crimean hemorrhagic fever.
B)St.Louis encephalitis virus and Coccidioides immitis.
C)Mycobacterium tuberculosis and Ebola.
D)Francisella tularensis and Ebola.

Question 56

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 57

The Joint Commission requires the following safety training to be documented in an employee's record except:

A)proper storage of gases.
B)biosafety level training.
C)bloodborne pathogen training.
D)hazardous materials management.

Question 58

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 59

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 laboratories except BSL-3 laboratories should:

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

Question 60

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.