Sterilization by radiation and Sterilization with ethylene oxide (EO) EUGMP- Annex-1
Questions 1. Sterilization by radiation is mainly used for:
A) Metal instruments
B) Heat-resistant materials
C) Heat-sensitive materials and products
D) Liquids only
Answer: C
Questions 2. Which method is not acceptable as a sterilization method?
A) Gamma irradiation
B) Electron-beam irradiation
C) Ultraviolet irradiation
D) Ionising radiation
Answer: C
Questions 3. Guidance on ionising radiation sterilisation can be found in:
A) Annex 1
B) Annex 12
C) Annex 5
D) Annex 8
Answer: B
Questions 4. Validation for radiation sterilisation should consider variation in:
A) pH of the product
B) Density of the product and packages
C) Ambient humidity
D) Storage conditions
Answer: B
Questions 5. Ethylene oxide sterilisation should be used:
A) As the preferred method
B) Only when no other method is practicable
C) For all heat-sensitive liquids
D) For metal components only
Answer: B
Questions 6. Validation of EO sterilisation must show:
A) EO increases product potency
B) No damaging effect on the product
C) EO gas remains in the product
D) Product colour changes
Answer: B
Questions 7. EO residuals after sterilisation must be reduced to:
A) Zero
B) Maximum possible
C) Defined acceptable limits
D) Supplier-defined limits
Answer: C
Questions 8. Direct contact between EO gas and microbes is essential to avoid:
A) Residual humidity
B) Organisms enclosed in crystals or dried protein
C) Over-pressurisation
D) Excess temperature
Answer: B
Questions 9. Packaging materials can significantly affect the EO process because of their:
A) Sterility assurance level
B) Nature, porosity, and quantity
C) Colour and branding
D) Thickness only
Answer: B
Questions 10. Before EO exposure, materials must be equilibrated with:
A) pH and viscosity requirements
B) Weight and density requirements
C) Required humidity and temperature
D) Light and pressure
Answer: C
Questions 11. When steam is used to condition the load before EO sterilization, it must be:
A) Sterile
B) At high pressure
C) Of appropriate quality
D) Superheated
Answer: C
Questions 12. Time required for conditioning before EO sterilisation should be:
A) As long as possible
B) Balanced against minimizing pre-sterilisation time
C) Avoided if possible
D) Determined only by the operator
Answer: B
Questions 13. EO sterilisation cycles must be monitored using:
A) Temperature charts
B) Pressure gauges
C) Suitable biological indicators (BIs)
D) Chemical indicators only
Answer: C
Questions 14. Biological indicators in EO cycles should be placed at:
A) Random locations
B) Corners of the chamber
C) Locations shown to be worst-case during validation
D) Near the door only
Answer: C
Questions 15. EO gas concentration is an example of:
A) Critical process parameter
B) Non-critical parameter
C) Packaging variable
D) Storage parameter
Answer: A
Questions 16. Which of the following is not listed as a critical EO parameter?
A) EO concentration
B) Relative humidity
C) Temperature
D) Product viscosity
Answer: D
Questions 17. Critical EO parameters include:
A) Exposure time
B) Light exposure
C) Operator training
D) Box stacking height
Answer: A
Questions 18. After EO sterilisation, the load must be:
A) Immediately shipped
B) Aerated
C) Frozen
D) Stored for 30 days
Answer: B
Questions 19. Aeration is necessary to allow EO gas and reaction products to:
A) Stabilize temperature
B) Increase humidity
C) Desorb to predetermined levels
D) Absorb into packaging
Answer: C
Questions 20. Aeration can be performed:
A) Only outside the steriliser
B) Only inside the steriliser
C) Either inside or in a separate chamber
D) Only in a cold room
Answer: C
Questions 21. The aeration phase for EO sterilisation must be:
A) Optional
B) Shortened as much as possible
C) Validated
D) Performed only by the supplier
Answer: C
Questions 22. Ultraviolet irradiation is unacceptable because it:
A) Is too expensive
B) Has insufficient penetrative power for sterilisation
C) Generates too much heat
D) Requires too much energy
Answer: B (implied by rejection as an acceptable sterilisation method)
Questions 23. EO process validation must show:
A) No interference with container colour
B) No microbial survival due to enclosed organisms
C) That EO does not damage the product
D) Reduced drying time
Answer: C
Questions 24. EO sterilisation effectiveness may be impacted by:
A) Colour of the packaging
B) Porosity and quantity of packaging materials
C) Operator gloves
D) Chamber lighting
Answer: B
Questions 25. The humidity required before EO exposure ensures:
A) Faster packaging
B) Operator safety
C) Effective sterilisation
D) Lower EO cost
Answer: C
Questions 26. EO pressure in the chamber is considered a:
A) Minor parameter
B) Critical process parameter
C) Supplier variable
D) Packaging attribute
Answer: B
Questions 27. Amount of EO gas used is monitored because:
A) It indicates packaging quality
B) It prevents over-humidification
C) It affects sterilisation effectiveness
D) It controls shipping conditions
Answer: C
Questions 28. Relative humidity during EO sterilisation must be:
A) Ignored
B) Kept at maximum
C) Controlled as a critical parameter
D) Avoided to keep materials dry
Answer: C
Questions 29. Temperature during EO sterilisation must be:
A) Uncontrolled
B) Maintained within validated limits
C) As high as possible
D) Equal to ambient temperature
Answer: B
Questions 30. Exposure time in the EO process must be:
A) Arbitrary
B) As short as possible
C) Included as a validated critical parameter
D) Determined by packaging supplier
Answer: C
Reference – EU Guidelines for GMP- Annex-1