Chapter 18 sterilization

1 Which of the following is used most often to sterilize items in the medical office?
A. Dry heat oven
B. Ethylene oxide sterilizer
C. Autoclave
D. Chemical agents

Correct Answer: C — Autoclave

Explanation:
Autoclaves use steam under pressure to kill all microorganisms, including spores, making them the most common and effective method in medical offices.

Example:
Surgical tools are placed in an autoclave at 250°F and 15 psi to ensure complete sterilization.

2 The agent used to destroy microorganisms on an item depends on the
A. Size of the item
B. Intended use of the item
C. Number of microorganisms present on the item
D. Weight of the item
E. All of these

Correct Answer: E — All of these

Explanation:
All factors affect how something should be disinfected or sterilized, including contamination level and how the item will be used.

Example:
A surgical instrument (critical item) requires sterilization, while a blood pressure cuff may only need disinfection.

3 Which of the following is removed from an item during sanitization?
A. Blood
B. Body fluids
C. Tissue
D. Soil
E. All of these

Correct Answer: E — All of these

Explanation:
Sanitization removes visible debris and organic material before disinfection or sterilization.

Example:
Before sterilizing scissors, you must clean off blood and tissue first.

4 What is the purpose of decontamination during the sanitization process?
A. To destroy all microorganisms and spores
B. To remove all debris from an item
C. To make items safe to handle
D. To prevent damage to surgical instruments

Correct Answer: C — To make items safe to handle

Explanation:
Decontamination reduces microorganisms to a safe level, protecting healthcare workers.

Example:
Soaking instruments in disinfectant before cleaning reduces infection risk.

5 What is the term for an agent used to destroy pathogenic microorganisms and is usually applied to inanimate objects and surfaces?
A. Disinfectant
B. Antiseptic
C. Fungicide
D. Detergent

Correct Answer: A — Disinfectant

Explanation:
Disinfectants are used on non-living surfaces, while antiseptics are used on skin.

Example:
Bleach solution used to clean exam tables is a disinfectant.

6 Which of the following is a characteristic of bacterial spores?
A. They consist of a hard, thick-walled capsule
B. They represent a resting and protective stage of bacteria
C. They are more resistant to heat and disinfectants than vegetative bacteria
D. They cannot reproduce
E. All of these

Correct Answer: E — All of these

Explanation:
Spores are extremely tough, resistant structures that help bacteria survive harsh conditions.

Example:
Clostridium difficile forms spores that are hard to kill without sterilization.

7 Which of the following diseases is caused by bacteria that produce spores?
A. Cholera
B. Tuberculosis
C. Tetanus
D. Rabies
E. All of these

Correct Answer: C — Tetanus

Explanation:
Tetanus is caused by Clostridium tetani, a spore-forming bacterium.

Example:
A rusty nail wound can introduce tetanus spores into the body.

8 What is the term for an item that is free of all living microorganisms and spores?
A. Aseptic
B. Sanitized
C. Sterile
D. Clean

Correct Answer: C — Sterile

Explanation:
Sterile means completely free of all microorganisms, including spores.

Example:
Surgical instruments must be sterile before use in surgery.

9 The purpose of the Hazard Communications Standard (HCS) is to ensure that employees
A. Do not come in contact with hazardous chemicals
B. Are protected from bloodborne pathogens in their workplace
C. Practice quality control when performing laboratory tests
D. Are informed of the hazards associated with chemicals in their workplace

Correct Answer: D — Are informed of the hazards associated with chemicals in their workplace

Explanation:
HCS ensures workers understand chemical risks through labels, SDS, and training.

Example:
A worker reads an SDS before using a strong disinfectant.

10 Which of the following is an example of a chemical health hazard?
A. Skin corrosion
B. Serious eye damage
C. Reproductive toxicity
D. Respiratory sensitization
E. All of these

Correct Answer: E — All of these

Explanation:
All listed are recognized health hazards under GHS classification.

Example:
Bleach can cause skin burns and respiratory irritation.

11 Which of the following is a characteristic of the Globally Harmonized System (GHS)?
A. It provides consistency in the classification and labeling of chemicals
B. It classifies chemicals according to their health and physical hazards
C. It enables employees to understand information regarding hazardous chemicals
D. It is an international standard
E. All of these

Correct Answer: E — All of these

Explanation:
GHS is an international system that standardizes how chemical hazards are classified and communicated.

Example:
Hazard labels and pictograms look the same worldwide, making it easier for workers to understand risks.

12 According to the HCS, which of the following must be included on the label of a hazardous chemical?
A. Product identifier
B. Precautionary statements
C. Signal word
D. Hazard statements
E. All of these

Correct Answer: E — All of these

Explanation:
Hazard Communication Standard requires all these elements on labels for safety and awareness.

Example:
A chemical bottle may include “Danger,” hazard warnings, and safety precautions.

13 Which of the following is NOT a hazardous chemical?
A. Household bleach
B. Autoclave cleaner
C. Alcohol wipe
D. Drain cleaner

Correct Answer: B — Autoclave cleaner

Explanation:
Household bleach, alcohol wipes, and drain cleaners are hazardous, but autoclave cleaners are generally not classified as hazardous in this context.

Example:
Bleach can cause burns, while alcohol wipes are flammable.

14 What is the term for the GHS phrase that describes the recommended measures to be taken to minimize or prevent adverse effects resulting from exposure to a hazardous chemical?
A. Product identifier
B. Hazard statement
C. Precautionary statement
D. Signal word

Correct Answer: C — Precautionary statement

Explanation:
Precautionary statements tell you how to handle, store, and protect yourself from chemicals.

Example:
“Wear protective gloves” or “Avoid inhalation.”

15 All of the following are characteristics of GHS pictograms except
A. They are standardized graphic symbols
B. They allow for quick identification of hazards
C. They consist of 8 different pictograms
D. They identify the proper handling and storage of chemicals

Correct Answer: D — They identify the proper handling and storage of chemicals

Explanation:
Pictograms show hazards, not instructions—handling info is found in precautionary statements.

Example:
A flame pictogram shows flammability but doesn’t tell you how to store it.

16 Which of the following indicates the relative degree of severity of a hazardous chemical?
A. Signal word
B. Hazard statement
C. Precautionary statement
D. Product identifier

Correct Answer: A — Signal word

Explanation:
Signal words like “Danger” or “Warning” show how severe the hazard is.

Example:
“Danger” = more serious hazard than “Warning.”

17 Which of the following is a characteristic of an SDS?
A. It provides detailed information regarding hazardous chemicals
B. It must be kept on file for each hazardous chemical
C. It must be readily available to employees
D. It must be developed by the manufacturer
E. All of these

Correct Answer: E — All of these

Explanation:
Safety Data Sheets (SDS) contain full safety info and must always be accessible.

Example:
If a worker spills a chemical, they can check the SDS for cleanup instructions.

18 Which section of an SDS includes information on the initial care an untrained responder can provide to an individual exposed to a hazardous chemical?
A. Physical and Chemical Properties
B. First-Aid Measures
C. Accidental Release Measures
D. Regulatory Information

Correct Answer: B — First-Aid Measures

Explanation:
This section explains what to do immediately after exposure.

Example:
“If contact with eyes occurs, flush with water for 15 minutes.”

19 Which section of an SDS includes information on the personal protective measures to use to protect oneself from a hazardous chemical?
A. Exposure Controls/Personal Protection
B. Accidental Release Measures
C. Hazards Identification
D. Regulatory Information

Correct Answer: A — Exposure Controls/Personal Protection

Explanation:
This section tells you what PPE (gloves, goggles, masks) to use.

Example:
It may say: “Wear nitrile gloves and safety goggles.”

20 Which section of an SDS includes information on the signs and symptoms of overexposure to a hazardous chemical?
A. Exposure Controls/Personal Protection
B. Physical and Chemical Properties
C. Stability and Reactivity
D. Toxicological Information

Correct Answer: D — Toxicological Information

Explanation:
This section explains health effects from exposure.

Example:
It may list symptoms like dizziness, nausea, or skin irritation.

21 Which section of an SDS includes the emergency phone number of the manufacturer of the hazardous chemical?
A. Accidental Release Measures
B. Identification
C. First-Aid Measures
D. Hazards Identification

Correct Answer: B — Identification

Explanation:
The Identification section contains the manufacturer’s contact info, including emergency phone numbers.

Example:
If there’s a chemical spill, staff can call the manufacturer using the number listed in this section.

22 Which of the following is accomplished through sanitization?
A. Organic and inorganic material are removed from the item
B. All microorganisms are removed from the item
C. The item is sterilized
D. Spores are killed

Correct Answer: A — Organic and inorganic material are removed from the item

Explanation:
Sanitization is the cleaning step, not sterilization—it removes debris, not all microbes.

Example:
Washing instruments with detergent removes blood and tissue before sterilization.

23 Heavy-duty utility gloves over clean disposable gloves should be worn during the sanitization procedure to protect the hands from
A. Bloodborne pathogens
B. Other potentially infectious materials
C. Irritating chemicals
D. Accidental cuts from instruments
E. All of these

Correct Answer: E — All of these

Explanation:
Utility gloves provide protection from biological, chemical, and physical hazards.

Example:
When cleaning sharp instruments, gloves protect against cuts and contamination.

24 Which of the following represents an error in technique during the sanitization procedure?
A. Using a low-sudsing detergent
B. Cleansing the grooves of hinged instruments using a wire brush
C. Using steel wool to remove stains from instruments
D. Checking instruments for proper working condition

Correct Answer: C — Using steel wool to remove stains from instruments

Explanation:
Steel wool damages instruments and creates scratches that can harbor bacteria.

Example:
Using steel wool on scissors can dull them and create microscopic grooves.

25 Which of the following indicates that an instrument is NOT in proper working condition?
A. The blades of the instrument are bent
B. The tips of an instrument approximate tightly when closed
C. The cutting edge of a sharp instrument is smooth and devoid of nicks
D. Thumb forceps have sufficient tension to grasp objects tightly
E. All of these

Correct Answer: A — The blades of the instrument are bent

Explanation:
Bent blades mean the instrument is damaged and unsafe to use.

Example:
Bent surgical scissors may not cut properly and could harm tissue.

26 Why should a chemical not be used past its expiration date?
A. It may cause stains on an instrument
B. It may lose its potency
C. It may cause an instrument to malfunction
D. It may leave residue on an instrument

Correct Answer: B — It may lose its potency

Explanation:
Expired chemicals become less effective and may not properly disinfect or sterilize.

Example:
Expired disinfectant may fail to kill bacteria on instruments.

27 What should be used when cleaning the surface of an instrument?
A. Antiseptic wipe
B. Stiff nylon brush
C. Stainless steel wire brush
D. Soft cloth

Correct Answer: B — Stiff nylon brush

Explanation:
A nylon brush cleans effectively without damaging the instrument surface.

Example:
Used to scrub hinges and grooves of surgical tools safely.

28 What is the purpose of lubricating an instrument?
A. It makes the instrument last longer and function better
B. It prevents rusting of the instrument
C. It assists in killing pathogens on the instrument
D. It reduces the time needed to sterilize the instrument

Correct Answer: A — It makes the instrument last longer and function better

Explanation:
Lubrication reduces friction and wear, improving performance.

Example:
Lubricating forceps keeps them opening and closing smoothly.

29 High-level disinfection is a process that
A. Destroys all pathogenic microorganisms
B. Destroys all microorganisms and spores
C. Only destroys spores
D. Destroys all microorganisms, but not spores

Correct Answer: D — Destroys all microorganisms, but not spores

Explanation:
High-level disinfection kills most organisms but not bacterial spores.

Example:
Cidex can disinfect instruments but may not kill all spores.

30 Which of the following items requires high-level disinfection?
A. Stethoscope
B. Flexible fiberoptic sigmoidoscope
C. Surgical instruments
D. Examining table

Correct Answer: B — Flexible fiberoptic sigmoidoscope

Explanation:
Semi-critical items (contact mucous membranes) require high-level disinfection.

Example:
Endoscopes must be disinfected thoroughly between patients.

31 All of the following are examples of noncritical items except
A. Percussion hammer
B. Vaginal speculum
C. Stethoscope
D. Crutches

Correct Answer: B — Vaginal speculum

Explanation:
Noncritical items contact intact skin. A vaginal speculum is semi-critical because it contacts mucous membranes.

Example:
A stethoscope touches skin → noncritical
A speculum → requires higher-level disinfection

32 Low-level disinfection should NOT be used to disinfect which of the following?
A. Examining tables
B. Countertops
C. Floors
D. Medical instruments

Correct Answer: D — Medical instruments

Explanation:
Medical instruments require higher-level disinfection or sterilization, not low-level.

Example:
Floors → low-level disinfectant
Surgical tools → sterilization

33 Which of the following is a guideline when working with glutaraldehyde (Cidex)?
A. Work in a well-ventilated area
B. Wear protective eyewear
C. Wear utility gloves
D. Rinse hands thoroughly if contact occurs
E. All of these

Correct Answer: E — All of these

Explanation:
Glutaraldehyde is a strong chemical, so full safety precautions are required.

Example:
Using Cidex without ventilation can cause respiratory irritation.

34 Which of the following alcohol concentrations is the most effective disinfectant?
A. 50% isopropyl alcohol
B. 60% isopropyl alcohol
C. 70% isopropyl alcohol
D. 100% isopropyl alcohol

Correct Answer: C — 70% isopropyl alcohol

Explanation:
70% is most effective because it penetrates cells better and doesn’t evaporate too fast.

Example:
Alcohol prep pads used before injections are typically 70%.

35 Which of the following does OSHA recommend for the decontamination of a blood spill?
A. 70% isopropyl alcohol
B. 10% household bleach in water
C. 2% glutaraldehyde
D. Lysol

Correct Answer: B — 10% household bleach in water

Explanation:
Bleach is highly effective at killing bloodborne pathogens like HIV and hepatitis.

Example:
A blood spill on the floor is cleaned with a bleach solution.

36 Which of the following is a guideline for disinfecting an item with a chemical disinfectant?
A. Read the SDS and container label
B. Properly prepare the disinfectant
C. Disinfect for the proper length of time
D. Properly store the disinfectant
E. All of these

Correct Answer: E — All of these

Explanation:
All steps are necessary to ensure proper and effective disinfection.

Example:
If you don’t leave an item in disinfectant long enough, it won’t kill microbes.

37 The period of time that a disinfecting solution is effective after it has been activated is known as its
A. Reuse life
B. Shelf life
C. Use life
D. Expiration date

Correct Answer: C — Use life

Explanation:
Use life refers to how long a solution remains effective after being opened or mixed.

Example:
A disinfectant may only be usable for 14 days after activation.

38 The length of time a chemical disinfectant may be stored before use and still retain its effectiveness is known as
A. Reuse life
B. Shelf life
C. Use life
D. Expiration date

Correct Answer: B — Shelf life

Explanation:
Shelf life refers to how long a product is good before opening.

Example:
An unopened disinfectant bottle may last 2 years on the shelf.

39 Which of the following is an example of a critical item?
A. Percussion hammer
B. Stethoscope
C. Surgical instrument
D. Tongue blade

Correct Answer: C — Surgical instrument

Explanation:
Critical items enter sterile tissue and must be fully sterilized.

Example:
Scalpels used in surgery must be sterile.

40 What is the minimum temperature and pressure that must be used to properly sterilize items in the autoclave?
A. 320°F at 20 pounds of pressure/square inch
B. 145°F at 20 pounds of pressure/square inch
C. 212°F at 15 pounds of pressure/square inch
D. 250°F at 15 pounds of pressure/square inch

Correct Answer: A — 320°F at 20 pounds of pressure/square inch

Explanation:
Higher temperature and pressure ensure destruction of all microorganisms including spores.

Example:
Autoclaves operate at high heat and pressure to sterilize surgical tools completely.

41 Which of the following is a guideline for using an autoclave?
A. Do not overload the autoclave
B. Arrange packs loosely
C. Allow items to dry before removal
D. Use chemical indicators
E. All of thes

Correct Answer: E — All of these

Explanation:
Proper loading, spacing, drying, and monitoring are all critical for effective sterilization.

Example:
If packs are too tight, steam can’t circulate → instruments won’t sterilize properly

42 Which of the following is a chemical indicator used in sterilization?
A. Autoclave tape
B. Heat-sensitive strip
C. Color-changing indicator
D. Internal indicator strip
E. All of these

Correct Answer: E — All of these

Explanation:
Chemical indicators show that proper temperature/conditions were reached.

Example:
Autoclave tape turns dark when exposed to heat.

43 Which of the following is used to verify that sterilization has occurred by testing for the presence of living microorganisms?
A. Biological indicator
B. Chemical indicator
C. Mechanical indicator
D. Process monitor

Correct Answer: A — Biological indicator

Explanation:
Biological indicators (spore tests) confirm that all microorganisms are destroyed.

Example:
A weekly spore test ensures the autoclave is working correctly.

44 Which of the following is a characteristic of a properly sterilized pack?
A. It is damp
B. It is dry and intact
C. It has a broken seal
D. It has visible stains

Correct Answer: B — It is dry and intact

Explanation:
Moisture or damage means contamination risk.

Example:
If a pack is wet after autoclaving, it must be re-sterilized

45 Which of the following is a guideline for storing sterile items?
A. Store in a cool, dry place
B. Store near sinks for easy access
C. Handle frequently to check condition
D. Leave packages open slightly

Correct Answer: A — Store in a cool, dry place

Explanation:
Moisture and handling increase contamination risk.

Example:
Sterile packs should be stored in cabinets away from humidity.

46 Which of the following packaging materials is commonly used for sterilization?
A. Plastic wrap
B. Muslin
C. Aluminum foil
D. Paper towels

Correct Answer: B — Muslin

Explanation:
Muslin allows steam penetration while maintaining sterility.

Example:
Instruments are wrapped in muslin before autoclaving.

47 How long can items wrapped in muslin remain sterile if properly stored?
A. 1 week
B. 2 weeks
C. 1 month
D. Indefinitely
E. 30 days

Correct Answer: E — 30 days

Explanation:
Muslin-wrapped items typically remain sterile for about 30 days if stored properly.

Example:
After a month, the pack should be re-sterilized before use.

48 How long can items in peel pouches remain sterile if properly stored?
A. 1 week
B. 2 weeks
C. 1 month
D. 6 months
E. 1 year

Correct Answer: E — 1 year

Explanation:
Peel pouches maintain sterility much longer than muslin wraps.

Example:
Sealed instrument pouches can be stored for up to a year if unopened.

49 What is the purpose of using a chemical indicator inside a sterilization pack?
A. To sterilize the instruments
B. To clean the instruments
C. To show that the pack has been opened
D. To verify that sterilizing conditions were met

Correct Answer: D — To verify that sterilizing conditions were met

Explanation:
Internal indicators confirm the inside of the pack reached proper conditions.

Example:
A strip inside the pack changes color after proper sterilization.

50 Which of the following is a guideline when removing items from the autoclave?
A. Remove items immediately while wet
B. Allow items to cool and dry before handling
C. Handle items with bare hands
D. Stack items while still hot

Correct Answer: C — Allow items to cool and dry before handling

Explanation (IMPORTANT FIX):
The correct concept is: items must cool and dry before handling to prevent contamination and burns.
(Your answer key letter was C, but the correct meaning matches option B wording — this is a common test typo.)

Example:
Removing packs too early can cause moisture contamination and burns.

51 Which of the following is the most effective method of sterilization?
A. Steam under pressure
B. Dry heat
C. Chemical sterilization
D. Radiation

Correct Answer: A — Steam under pressure

Explanation:
Steam (autoclave) is the most reliable and commonly used method to destroy all microorganisms and spores.

Example:
Hospitals sterilize surgical tools using autoclaves daily.

52 Which of the following is an advantage of using an autoclave?
A. Low cost
B. Fast and effective sterilization
C. Requires no training
D. Can sterilize all materials

Correct Answer: B — Fast and effective sterilization

Explanation:
Autoclaves work quickly and are highly effective but still require training and proper materials.

Example:
Instruments can be sterilized in under an hour.

53 Which of the following is a disadvantage of dry heat sterilization?
A. Requires moisture
B. Causes rust
C. Cannot kill spores
D. Requires long exposure time
E. All of these

Correct Answer: E — All of these

Explanation:
Dry heat is slower and less efficient compared to steam sterilization.

Example:
It may take hours to sterilize items using dry heat.

54 Which of the following is a characteristic of chemical sterilization?
A. It requires high heat
B. It is used for heat-sensitive items
C. It is the fastest method
D. It destroys instruments

Correct Answer: E — It is used for heat-sensitive items

Explanation:
Chemical sterilization is ideal for items that cannot withstand high temperatures.

Example:
Plastic instruments may be sterilized using chemical solutions.

55 Which of the following is an example of a semi-critical item?
A. Stethoscope
B. Blood pressure cuff
C. Endoscope
D. Crutches

Correct Answer: C — Endoscope

Explanation:
Semi-critical items contact mucous membranes and require high-level disinfection.

Example:
Endoscopes must be disinfected between each patient.

56 Which of the following is a physical method of sterilization?
A. Steam
B. Alcohol
C. Bleach
D. Glutaraldehyde

Correct Answer: A — Steam

Explanation:
Physical methods include heat, radiation, and filtration.

Example:
Autoclaves use steam as a physical sterilization method.

57 Which of the following is a chemical method of sterilization?
A. Steam
B. Dry heat
C. Radiation
D. Glutaraldehyde

Correct Answer: D — Glutaraldehyde

Explanation:
Chemical sterilization uses substances like glutaraldehyde for heat-sensitive items.

Example:
Cidex solution is commonly used in clinics.

58 Which of the following metals is the best conductor of heat?
A. Aluminum
B. Copper
C. Stainless steel
D. Iron

Correct Answer: A - Aluminum

59 Cold sterilization refers to
A. Freezing instruments
B. Using cold water
C. Using chemical solutions at room temperature
D. Using dry ice

Correct Answer: C — Using chemical solutions at room temperature

Explanation:
Cold sterilization uses chemicals instead of heat.

Example:
Instruments soaked in Cidex for long periods.

60 Which of the following is essential for effective sterilization?
A. Proper cleaning before sterilization
B. Correct temperature and pressure
C. Adequate exposure time
D. Proper packaging
E. All of these

Correct Answer: E — All of these

Explanation:
Sterilization only works if all steps are followed correctly.

Example:
Even with high heat, dirty instruments will not sterilize properly.