CSPT Cleanroom Facilities and Equipment 4 — Questions and Answers
Question 1: Which ISO classification requires air particle counts of no more than 3,520 particles ≥0.5 µm per cubic meter?
- ISO Class 5 (Correct answer)
- ISO Class 7
- ISO Class 8
- ISO Class 4
Correct answer: ISO Class 5
ISO Class 5 permits a maximum of 3,520 particles ≥0.5 µm per cubic meter and is required for the critical zone where sterile preparations are made.
Question 2: What action should be taken if the primary engineering control (PEC) HEPA filter fails certification during routine testing?
- Immediately cease compounding until the filter is repaired or replaced (Correct answer)
- Continue compounding using extra PPE as a precaution
- Notify the pharmacist but continue low-risk compounding only
- Reduce airflow speed to prevent further damage
Correct answer: Immediately cease compounding until the filter is repaired or replaced
USP <797> requires that compounding cease immediately when a PEC fails certification, as sterility of preparations can no longer be assured.
Question 3: The 'first air' concept in laminar airflow workbenches refers to:
- Air that has passed through the HEPA filter before contacting any surface or critical site (Correct answer)
- The initial airflow burst when the BLAC is first powered on
- Air recirculated from the room into the HEPA filter
- The exhaust air expelled outside the cleanroom
Correct answer: Air that has passed through the HEPA filter before contacting any surface or critical site
First air is the unobstructed HEPA-filtered air directly from the filter face, which must reach critical sites without being deflected by objects or hands.
Question 4: How frequently must viable air sampling (active air monitoring) be performed in a cleanroom buffer area under USP <797>?
- Monthly (Correct answer)
- Every 6 months
- Annually
- Every 3 months
Correct answer: Monthly
USP <797> (2023) requires viable air sampling in the buffer area to be performed at least monthly.
Question 5: Which of the following best describes the function of the anteroom in a sterile compounding facility?
- It serves as a transition zone where personnel don PPE and maintain a pressure differential buffer (Correct answer)
- It is where final product labeling and QA checks are performed
- It houses the primary engineering control for sterile compounding
- It is used exclusively for storage of compounded preparations
Correct answer: It serves as a transition zone where personnel don PPE and maintain a pressure differential buffer
The anteroom is a transitional space used for gowning, hand hygiene, and maintaining a pressure gradient between unclassified and classified areas.
Question 6: When disinfecting a laminar airflow workbench (LAFW), in which direction should the technician wipe the work surface?
- From back to front in overlapping, side-to-side strokes (Correct answer)
- From front to back in a single continuous motion
- In circular motions starting from the center outward
- From left to right only, avoiding the HEPA filter
Correct answer: From back to front in overlapping, side-to-side strokes
Wiping from back to front using overlapping side-to-side strokes moves contamination away from the HEPA filter toward the operator, preventing recontamination of the clean zone.
Question 7: A compounding technician notices that the pressure differential gauge between the buffer room and anteroom reads a positive value in a hazardous drug compounding suite. This indicates:
- A problem — hazardous drug rooms must maintain negative pressure relative to adjacent areas (Correct answer)
- Normal — all compounding areas require positive pressure
- A minor calibration issue that can be corrected during next scheduled maintenance
- Acceptable only if the HEPA filter is certified ISO Class 5
Correct answer: A problem — hazardous drug rooms must maintain negative pressure relative to adjacent areas
Hazardous drug compounding areas must maintain negative pressure (≥0.01–0.03 inch water column) relative to adjacent spaces to contain drug particles and protect personnel.
