TECHNICAL COLLEGE OF ENGINEERING

Medical Instruments Technical Engineering Dep.

Autoclave (MCQ)

Rasool Al-Gburi
Autoclave (MCQ) Rasool Al-Gburi

1. What is the primary purpose of an autoclave?

a. Cooling materials under pressure
b. Sterilizing materials using steam under pressure
c. Drying materials using hot air
d. Preserving materials using cold storage

2. What type of heat does an autoclave use for sterilization?

a. Dry heat
b. Infrared heat
c. Moist heat
d. Radiant heat

3. What makes the autoclave more effective as a sterilization method?

a. Its use of radiation
b. Its reliance on moist heat sterilization
c. Its use of chemical disinfectants
d. Its ability to freeze materials

4. What is another name for an autoclave?

a. Heat dryer
b. Pressure cooker
c. Steam sterilizer
d. Vacuum oven

5. What is the primary component of an autoclave called?

a. Heating element
b. Pressure gauge
c. Pressure chamber
d. Safety valve

6. What material is the inner chamber of a steam autoclave typically made of?
a. Iron
b. Aluminum
c. Stainless steel or gunmetal
d. Plastic

7. What material is the outer jacket of the pressure chamber typically made of?
a. Plastic
b. Iron case
c. Copper
d. Stainless steel

8. What feature of the outer jacket in healthcare autoclaves helps reduce the time
needed to reach the sterilization temperature?
a. Air circulation
b. Steam filling
c. Electrical heating
d. Insulation

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Autoclave (MCQ) Rasool Al-Gburi

9. Where are the materials to be sterilized placed in an autoclave?

a. Outer jacket
b. Heating element
c. Inner chamber
d. Pressure valve

10. What is the primary purpose of the lid or door in an autoclave?

a. To heat the materials
b. To release excess steam
c. To seal off the outside atmosphere and create a sterilized condition inside
d. To support the pressure gauge

11. How is the autoclave lid made airtight?

a. Using silicone gaskets
b. Using screw clamps and asbestos washer
c. Using rubber seals
d. By manual tightening

12. What is the typical size range of the pressure chamber in an autoclave?
a. 50 L to 500 L
b. 200 L to 2500 L
c. 100 L to 3000 L
d. 500 L to 3500 L

13. What is the primary function of the pressure gauge on an autoclave?

a) To heat the chamber
b) To measure the temperature
c) To indicate the pressure created during sterilization
d) To release excess pressure

14. Where is the pressure gauge located on an autoclave?

a) Inside the chamber
b) On the outer jacket
c) On the lid of the autoclave
d) Near the heating element

15. Why is the pressure gauge important in an autoclave?

a) It ensures the proper heating of samples
b) It guarantees the safety and working condition of the autoclave
c) It regulates the flow of steam
d) It indicates the sterilization time

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Autoclave (MCQ) Rasool Al-Gburi

16. What does the pressure gauge measure in an autoclave?

a) The amount of steam
b) The temperature of the chamber
c) The pressure inside the chamber
d) The humidity level

17. If the pressure gauge malfunctions, what could be a potential risk?

a) Inaccurate temperature readings
b) Inadequate sterilization or over-pressurization
c) Reduced steam generation
d) Faster sterilization cycles

18. What is the purpose of the whistle present on the lid of an autoclave?
a) To monitor temperature
b) To release excess liquid
c) To control pressure inside the chamber by releasing vapor
d) To prevent condensation

19. What is the primary purpose of a wastewater cooler in an autoclave?

a) To sterilize the effluent water
b) To cool the effluent before it is used again
c) To prevent damage to the drainage pipes
d) To ensure the autoclave operates at maximum efficiency

20. How does the wastewater cooler protect the drainage pipes?
a) By filtering impurities from the effluent
b) By cooling the boiling water before discharge
c) By increasing the water pressure in the system
d) By sterilizing the pipes

21. What happens if the wastewater cooler is not used in an autoclave system?
a) The autoclave may overheat
b) The drainage pipes might get clogged
c) The sterilization process might fail
d) The drainage pipes may be damaged by boiling water

22. What principle does an autoclave work on?

a) Dry heat sterilization
b) Moist heat sterilization
c) Ultraviolet sterilization
d) Chemical sterilization

23. How does high pressure in an autoclave aid sterilization?

a) By reducing the boiling point of water
b) By drying the material being sterilized
c) By increasing the boiling point of water and achieving higher temperatures
d) By preventing heat loss

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Autoclave (MCQ) Rasool Al-Gburi

24. What is the boiling point of water under normal atmospheric pressure (760 mm of
Hg)?
a) 90°C
b) 110°C
c) 100°C
d) 120°C

25. What effect does the high pressure have on microbes in the material being
sterilized?
a) It dries out the microbes completely
b) It deactivates the DNA of the microbes
c) It causes coagulation of proteins, leading to an irreversible loss of function
d) It prevents the microbes from reproducing

26. What role does moisture in steam play in the sterilization process?
a) It cools the chamber to prevent overheating
b) It helps coagulate proteins in microbes, causing their destruction
c) It maintains the chamber's pressure
d) It prevents the material from drying out

27. At what temperature does water boil in an autoclave at 15 psi pressure?

a) 100°C
b) 110°C
c) 121°C
d) 130°C

28. What happens when steam comes in contact with a surface during sterilization?
a) It dries the microbes
b) It condenses without any effect
c) It kills the microbes by releasing latent heat
d) It decreases the surface temperature

29. What ensures the moist killing of microbes in an autoclave?

a) High pressure
b) Latent heat
c) Condensed liquid
d) Steam movement

30. How is the pressure inside the autoclave released after sterilization?
a) By opening the chamber manually
b) Through the whistle
c) By cooling the autoclave rapidly
d) By evaporating the condensed water

31. What happens to the pressure inside the autoclave after the sterilization phase is
completed?
a) It remains at 15 psi
b) It increases temporarily
c) It is restored back to ambient pressure
d) It fluctuates based on the material inside

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Autoclave (MCQ) Rasool Al-Gburi

32. What happens to the components inside the autoclave after the pressure is released?
a) They cool down immediately
b) They remain hot for some time
c) They dry out completely
d) They lose all moisture

33. Which type of autoclave is similar to a domestic pressure cooker?

a) Vacuum autoclave
b) Horizontal autoclave
c) Pressure cooker type/Laboratory bench autoclaves (N-type)
d) High-capacity autoclave

34. What is used to seal the lid of a pressure cooker-type autoclave?

a) Metal clamps
b) A rubber gasket
c) A plastic seal
d) Adhesive tape

35. What components are typically found in a pressure cooker-type autoclave?

a) Air pump, thermostat, and safety switch
b) Air and steam discharge tap, pressure gauge, and safety valve
c) Cooling fan, heating rod, and pressure sensor
d) Vacuum pump, condenser, and safety latch

36. What provides heat in a pressure cooker-type autoclave?

a) Gas burner
b) External heating plate
c) Electric immersion heater
d) Steam generator

37. What is the purpose of the pressure gauge in a pressure cooker-type autoclave?
a) To measure temperature inside the chamber
b) To monitor the pressure inside the chamber
c) To control the steam flow
d) To activate the heater

38. What is the most common type of autoclave used in laboratories?

a) Vacuum autoclave
b) Horizontal autoclave
c) Gravity displacement type autoclave
d) Pressure cooker type autoclave

39. How is steam created in a gravity displacement autoclave?

a) By injecting steam from an external source
b) By a heating unit inside the chamber
c) By using a vacuum pump to boil water
d) By releasing compressed air into the chamber

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Autoclave (MCQ) Rasool Al-Gburi

40. What happens to the steam after it is generated in a gravity displacement autoclave?
a) It exits the chamber immediately
b) It condenses to form water
c) It moves around the chamber for sterilization
d) It remains stationary to maintain pressure

41. What is one advantage of a gravity displacement autoclave compared to other types?
a) It is faster in sterilization
b) It requires less maintenance
c) It is comparatively cheaper
d) It consumes less electricity

42. Where is the steam generated in a positive pressure displacement type (B-type)
autoclave?
a) Inside the autoclave chamber
b) In a separate steam generator
c) By an external boiler
d) By a heating element inside the lid

43. What is the advantage of a positive pressure displacement type (B-type) autoclave
over other types?
a) It is cheaper to operate
b) It requires no external power source
c) It is faster because steam can be generated within seconds
d) It uses less water

44. What makes the positive pressure displacement type (B-type) autoclave an
improvement over the gravity displacement type?
a) It consumes less electricity
b) It is more energy-efficient
c) It can generate steam more quickly
d) It is smaller in size

45. What two components are present in a negative pressure displacement type (S-type)
autoclave?
a) Steam generator and air filter
b) Steam generator and vacuum generator
c) Heating unit and pressure valve
d) Water tank and steam nozzle

46. What is the role of the vacuum generator in a negative pressure displacement type
(S-type) autoclave?
a) To heat the water
b) To remove all the air from inside the autoclave
c) To create high pressure
d) To condense the steam

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Autoclave (MCQ) Rasool Al-Gburi

47. Why is the negative pressure displacement type (S-type) autoclave highly
recommended?
a) It is cheaper than other types
b) It operates faster than others
c) It is very accurate and achieves a high sterility assurance level
d) It is smaller and more compact

48. What is a drawback of the negative pressure displacement type (S-type) autoclave?
a) It requires a larger chamber
b) It is more difficult to operate
c) It is the most expensive type of autoclave
d) It has a longer sterilization time

49. What is one of the primary uses of an autoclave?

a) To cool materials quickly
b) To sterilize materials containing water
c) To freeze biological samples
d) To separate contaminants from materials

50. What type of waste is recommended to be inactivated by autoclaving before

disposal?
a) Paper waste
b) Regulated medical waste containing bacteria, viruses, and other biological materials
c) Chemical waste
d) Plastic waste

51. What types of equipment are typically sterilized in medical labs using autoclaves?
a) Computer equipment
b) Medical equipment, glassware, surgical instruments, and medical wastes
c) Electrical components
d) Food packaging

52. Which items can be sterilized using autoclaves?

a) Wood and metals
b) Culture media, autoclavable containers, plastic tubes, and pipette tips
c) Electrical devices
d) Food items

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