CSPT - Compounded Sterile Preparation Technician Cleanroom Facilities and Equipment Questions and Answers 2 — Questions and Answers
Question 1: What is the required ISO classification for the buffer area in a sterile compounding facility?
- ISO Class 5
- ISO Class 6
- ISO Class 7 (Correct answer)
- ISO Class 8
Correct answer: ISO Class 7
The buffer area must maintain ISO Class 7 air quality conditions per USP 797.
USP 797 establishes a hierarchy of air quality zones. The buffer area must maintain ISO Class 7 conditions (maximum 352,000 particles per cubic meter at 0.5 microns or larger). This room houses the primary engineering control which itself maintains ISO Class 5.
Question 2: How often should HEPA filters in a laminar airflow workbench be certified?
- Monthly
- Quarterly
- Every 6 months (Correct answer)
- Annually
Correct answer: Every 6 months
HEPA filters in LAFWs and other PECs must be certified at least every 6 months.
USP 797 requires certification of all primary engineering controls at least every 6 months. Certification includes DOP or PAO challenge testing to verify HEPA filter integrity, airflow velocity measurements, and smoke pattern studies.
Question 3: What is the primary difference between a horizontal LAFW and a vertical LAFW?
- Horizontal LAFWs are larger
- In a horizontal LAFW air flows back to front; in a vertical LAFW air flows top to bottom (Correct answer)
- Horizontal LAFWs use ULPA filters
- Vertical LAFWs cannot be used for sterile compounding
Correct answer: In a horizontal LAFW air flows back to front; in a vertical LAFW air flows top to bottom
The key difference is airflow direction: horizontal LAFWs push air from the back wall toward the technician, while vertical LAFWs direct air downward from the top.
In a horizontal LAFW, the HEPA filter is mounted on the back wall and pushes filtered air horizontally toward the front. Vertical LAFWs have the HEPA filter mounted in the ceiling and push air straight down onto the work surface.
Question 4: What is the purpose of a pressure differential between the buffer area and the ante-area?
- To keep temperatures consistent
- To prevent less clean air from flowing into the cleaner buffer area (Correct answer)
- To reduce humidity
- To increase HEPA filter efficiency
Correct answer: To prevent less clean air from flowing into the cleaner buffer area
A positive pressure differential ensures air flows from the cleaner buffer area outward to the less clean ante-area, preventing contamination.
USP 797 requires a minimum positive pressure differential of 0.020 inches of water column between the buffer area and the ante-area. This ensures that when doors open, airflow direction is always outward from the cleaner space.
Question 5: Which cleaning agent is recommended for daily cleaning of the interior surfaces of a LAFW?
- Bleach solution only
- Sterile 70% isopropyl alcohol (Correct answer)
- Hydrogen peroxide 3%
- Quaternary ammonium compound
Correct answer: Sterile 70% isopropyl alcohol
Sterile 70% IPA is the standard agent for daily cleaning of LAFW interior surfaces.
Sterile 70% IPA is the primary disinfectant for daily cleaning of LAFW interiors per USP 797. A sporicidal agent should be used periodically (at least monthly) in addition to IPA, since IPA alone is not effective against bacterial spores.
Question 6: What does a Biological Safety Cabinet (BSC) provide that a standard horizontal LAFW does not?
- Higher air velocity
- Personnel protection through inward airflow at the front opening (Correct answer)
- Better product sterility
- Reduced noise levels
Correct answer: Personnel protection through inward airflow at the front opening
A BSC provides both product protection and personnel protection through inward airflow at the front opening and downward HEPA-filtered air.
A BSC draws room air inward at the front opening, creating an air curtain that prevents hazardous aerosols from escaping toward the technician. Simultaneously, HEPA-filtered air flows downward over the work surface to maintain product sterility. Standard LAFWs blow air toward the technician, providing product protection only.
CSPT - Compounded Sterile Preparation Technician Cleanroom Facilities and Equipment Questions and Answers 2
What is the required ISO classification for the buffer area in a sterile compounding facility?