22 Facilities & Equipment Practice Questions & Answers

1. 1. A horizontal laminar airflow workbench blows HEPA-filtered air across the work surface and out toward the operator. What does this airflow pattern tell a technician about how the workbench may be used?

   • A.It protects the preparation but not the operator, so hazardous drugs must not be compounded in it.✓ Answer
   • B.It protects the operator but not the preparation, so it suits hazardous drugs and nothing else.
   • C.It protects the room air but not the preparation, so it is used only to stage supplies before use.
   • D.It protects both the operator and the preparation, so any injectable drug may be prepared in it.

   The filtered stream leaves the HEPA filter, passes over the critical sites and then exits toward the technician, so nothing carries drug aerosol away from the breathing zone. Sterile compounding of hazardous drugs requires a containment device that draws air away from the operator and is exhausted to the outdoors.

   Source: USP General Chapter <797> Pharmaceutical Compounding — Sterile Preparations, primary engineering controls and direction of airflowReport a problem with this question

2. 2. A pharmacy is choosing a cabinet in which to compound hazardous injectable drugs. Which feature makes a cabinet appropriate for that work?

   • A.A containment design intended for non-sterile work, drawing unfiltered room air across the opening.
   • B.A cabinet that HEPA-filters its entire exhaust and returns all of that air into the buffer room.
   • C.Filtered air that sweeps horizontally across the preparation and out through the front opening.
   • D.A downward flow of HEPA-filtered air over the preparation, with the cabinet exhausted to the outdoors.✓ Answer

   Worker protection depends on drug-laden air being pulled away from the operator and vented outside the building rather than recirculated, while the downward HEPA-filtered stream protects the preparation at the same time. A cabinet built only for non-sterile containment does not deliver the air quality a sterile preparation requires.

   Source: USP General Chapter <800> Hazardous Drugs — Handling in Healthcare Settings, containment primary engineering controlsReport a problem with this question

3. 3. How does a compounding aseptic containment isolator differ from a compounding aseptic isolator used for non-hazardous work?

   • A.It holds a negative pressure inside and is externally vented, so drug aerosols stay contained.✓ Answer
   • B.It holds a positive pressure inside its chamber and is unvented, so room air can never enter it.
   • C.It filters only the air entering the chamber and releases the chamber air into the room untreated.
   • D.It uses the same airflow as the aseptic isolator, and the different name reflects only a larger chamber.

   Containment is achieved by keeping the interior at a lower pressure than the surrounding room and venting the chamber air outside, so any drug aerosol generated during manipulation cannot escape into the room. An aseptic isolator without those features protects the preparation only.

   Source: USP General Chapter <800> Hazardous Drugs — Handling in Healthcare Settings, containment isolatorsReport a problem with this question

4. 4. While compounding in a horizontal workbench, a technician sets a stack of alcohol-wipe packets between the HEPA filter and the vial being punctured. Why is this a problem?

   • A.The packets interrupt first air, so air reaching the vial has already passed over another object.✓ Answer
   • B.The packets reduce the airflow enough to lower the room's air changes below the required rate.
   • C.The packets warm the air stream, raising the humidity of the air reaching the vial's critical site.
   • D.The packets add mass to the work surface, which alters the calibration of the airflow sensors.

   First air is HEPA-filtered air that has touched nothing since leaving the filter face, and it is the organizing idea of the whole work zone: the critical site must be the first thing that air reaches. Once the stream passes over an object it can carry particles shed from that object downstream onto the puncture site.

   Source: USP General Chapter <797> Pharmaceutical Compounding — Sterile Preparations, first air and critical sitesReport a problem with this question

5. 5. A technician brings a covered coffee cup and a cell phone into the buffer room to use during a long batch. How should this be handled?

   • A.Neither item may be brought in; food, drink and personal items are prohibited in classified areas.✓ Answer
   • B.Both may be brought in as long as they are wiped with a disinfectant before entering the room.
   • C.The drink may stay if it is kept closed, but the phone must be left outside the anteroom.
   • D.Both may stay if they remain on a shelf outside the line of demarcation in the buffer room.

   Food, drink, gum, tobacco and personal items shed particles and microorganisms, cannot be reliably disinfected, and invite hand-to-face contact, so they are excluded from classified areas and from a segregated compounding area alike. Wiping the outside does not make an item acceptable.

   Source: USP General Chapter <797> Pharmaceutical Compounding — Sterile Preparations, operational standards for classified areasReport a problem with this question

6. 6. A clinic compounds in a designated unclassified area that contains a workbench but has no anteroom or buffer room. What does this setting allow?

   • A.Any sterile preparation may be compounded there if all starting components are sterile.
   • B.Only preparations in the category carrying the most limited beyond-use dating may be compounded.✓ Answer
   • C.Preparations may be compounded there only while the hand-washing sink sits beside the workbench.
   • D.Hazardous preparations may be compounded there when a closed-system transfer device is used.

   A segregated compounding area is a defined space that houses a primary engineering control but whose surrounding air is not ISO-classified, so the environment cannot support extended dating and only the shortest-dated category may be prepared. The sink must be far enough from the workbench that splashing cannot reach it, not beside it.

   Source: USP General Chapter <797> Pharmaceutical Compounding — Sterile Preparations, segregated compounding areasReport a problem with this question

7. 7. What is the purpose of a containment segregated compounding area?

   • A.It provides a place to store hazardous drugs that require no further containment.
   • B.It houses a containment cabinet for hazardous preparations limited to the shortest dating.✓ Answer
   • C.It provides an unclassified space where hazardous and non-hazardous work may share a cabinet.
   • D.It replaces the containment buffer room for any hazardous preparation the pharmacy makes.

   The containment segregated compounding area is a negative-pressure, externally vented room that is not ISO-classified but holds a containment primary engineering control, so it supports only the shortest-dated hazardous preparations. It does not replace a containment buffer room, and hazardous and non-hazardous work are not performed in the same device.

   Source: USP General Chapter <800> Hazardous Drugs — Handling in Healthcare Settings, containment segregated compounding areaReport a problem with this question

8. 8. Why is a buffer room used for non-hazardous compounding kept at a positive pressure relative to its anteroom?

   • A.So the relative humidity in the buffer room falls, limiting mold growth on the room surfaces.
   • B.So air flows out of the buffer room through openings, keeping less clean air from flowing in.✓ Answer
   • C.So the air velocity at the face of the workbench rises, improving first air at the critical sites.
   • D.So air flows into the buffer room through openings, pulling airborne drug residue away from staff.

   Air always moves from higher to lower pressure, so holding the cleaner room above the less clean one makes every gap, door crack and opening a one-way outward flow that pushes contamination away. The pressure relationship, not the door itself, is what keeps anteroom air out of the buffer room.

   Source: USP General Chapter <797> Pharmaceutical Compounding — Sterile Preparations, pressure differentials in a cleanroom suiteReport a problem with this question

9. 9. A containment buffer room for hazardous compounding is held at a negative pressure relative to the adjoining anteroom. Why is this direction correct?

   • A.Air leaves the room through openings, which keeps particles shed in the anteroom from entering.
   • B.Air enters the room through openings, which keeps drug contamination from reaching adjacent areas.✓ Answer
   • C.Negative pressure helps the containment cabinet keep the preparation itself free of microorganisms.
   • D.Negative pressure permits the room's exhaust to be recirculated into the building's supply air.

   The two pressure directions answer two different questions: positive pressure keeps contamination out of a non-hazardous room, while negative pressure keeps hazardous drug residue in. Because air moves inward at every opening, drug contamination cannot drift into the anteroom or corridor, and the room's air is exhausted outdoors rather than recirculated.

   Source: USP General Chapter <800> Hazardous Drugs — Handling in Healthcare Settings, containment room designReport a problem with this question

10. 10. The anteroom serving a negative-pressure containment buffer room is itself held positive to the unclassified space outside it. What does that accomplish?

    • A.Air moves from the anteroom toward the containment room, so contamination is not carried outward.✓ Answer
    • B.The containment room's exhaust can be shut down at night without losing its containment function.
    • C.The anteroom may then be used to store hazardous drugs once suitable shelving has been installed.
    • D.Air moves from the corridor into the anteroom, so the anteroom needs no HEPA-filtered supply air.

    Stacking the pressures in this order creates a continuous inward cascade: air moves from the least clean outside space up into the positive anteroom and then on into the negative containment room, where it is exhausted. The gowned technician enters through progressively cleaner air while hazardous residue is always pulled deeper in rather than out.

    Source: USP General Chapter <800> Hazardous Drugs — Handling in Healthcare Settings, anteroom serving a containment roomReport a problem with this question

11. 11. What does the HEPA filter supplying a primary engineering control actually do to the air?

    • A.It destroys chemical vapors from hazardous drugs so the exhaust may be returned to the room.
    • B.It removes airborne particles and also disinfects the surfaces that the air flows across.
    • C.It sterilizes the air by heating it as it is drawn through the pleated filter medium.
    • D.It removes airborne particles, including the microorganisms that are carried on them.✓ Answer

    HEPA filtration is a mechanical process, not a chemical or thermal one: it traps particulate matter, and because microorganisms travel attached to skin fragments and dust, removing the particles removes the organisms riding on them. It does nothing to surfaces or to chemical vapor, which is why surface disinfection and external venting are separate requirements.

    Source: USP General Chapter <797> Pharmaceutical Compounding — Sterile Preparations, HEPA filtration of air supplied to compounding areasReport a problem with this question

12. 12. Why is HEPA-filtered air supplied to a classified room continuously, rather than only while compounding is under way?

    • A.Continuous supply constantly dilutes and removes the particles that people and activity shed.✓ Answer
    • B.Continuous supply keeps the filters from clogging during the hours the room sits unoccupied.
    • C.Continuous supply keeps the room's surfaces disinfected between scheduled cleaning sessions.
    • D.Continuous supply holds the components stored in the room at the temperature their labeling requires.

    A cleanroom does not stay clean by itself; people, garments, packaging and movement generate particles the whole time the room is in use, and the only mechanism that removes them is repeated exchange of the room's air with filtered air. Interrupting the supply lets particle burden build up, so the room must be allowed to recover before compounding resumes.

    Source: USP General Chapter <797> Pharmaceutical Compounding — Sterile Preparations, air exchange in classified areasReport a problem with this question

13. 13. What does the ISO classification assigned to a compounding room express?

    • A.The largest number of people who may occupy the room while compounding is under way.
    • B.The largest number of colony-forming units that may be recovered from the room's surfaces.
    • C.The largest concentration of airborne particles of a given size allowed in the room's air.✓ Answer
    • D.The smallest volume of HEPA-filtered air the room's ventilation must deliver each hour.

    An ISO classification is a non-viable particle standard: it caps how many particles of a stated size may be suspended in a volume of air, which is why it is verified by particle counting under dynamic conditions. It says nothing directly about microorganisms, which viable air and surface sampling measure separately.

    Source: USP General Chapter <797> Pharmaceutical Compounding — Sterile Preparations, ISO classification of compounding areasReport a problem with this question

14. 14. Several staff members who are not compounding gather in the buffer room to discuss the schedule. Why should the supervisor intervene?

    • A.Non-compounding staff may enter only after the day's environmental samples have been taken.
    • B.People shed particles and organisms, so occupancy and movement in the room must be minimized.✓ Answer
    • C.Conversation raises the room's humidity above the level the ventilation system can correct.
    • D.Extra occupants change the room's pressure differential and invalidate that day's readings.

    Humans are the dominant source of contamination in a compounding area: skin, hair and speech generate particles and droplets, and movement stirs up settled ones. Access is restricted to trained, authorized personnel, and everyone who enters — including certifiers, service technicians and housekeeping — must be trained and appropriately garbed.

    Source: USP General Chapter <797> Pharmaceutical Compounding — Sterile Preparations, access and personnel movement in compounding areasReport a problem with this question

15. 15. Why is relative humidity controlled and documented in a classified compounding area?

    • A.High humidity reduces the pressure differential between the buffer room and the anteroom.
    • B.High humidity increases the particle count of the supply air by loading the HEPA filter.
    • C.High humidity encourages microbial and mold growth on room surfaces and stored items.✓ Answer
    • D.High humidity shortens the shelf life of the disinfectant stored in the anteroom cabinet.

    Moisture is what mold and many bacteria need to proliferate on surfaces, packaging and garb, so an upward drift in humidity shows up later as out-of-specification surface or air monitoring. Damp conditions also make garb uncomfortable and increase the movement that spreads particles, which is why the reading is recorded on days compounding occurs.

    Source: USP General Chapter <797> Pharmaceutical Compounding — Sterile Preparations, temperature and humidity monitoring in classified areasReport a problem with this question

16. 16. During a batch, a technician notices the buffer room's pressure reading has drifted outside the facility's specified range. What is the correct response?

    • A.Adjust the gauge to the middle of the range and continue, then report it at end of shift.
    • B.Stop, notify the pharmacist, and quarantine affected preparations until it is investigated.✓ Answer
    • C.Finish the batch and note the reading in the log, since the workbench air remains filtered.
    • D.Move the remaining work to the anteroom bench and finish the batch outside the buffer room.

    The pressure differential is the mechanism that keeps less clean air out of the room, so once it is out of specification the air quality supporting those preparations can no longer be assumed. Work stops, the pharmacist decides the disposition of what has already been made, and the cause is investigated and corrected before compounding resumes; adjusting a gauge or moving work to an unsuitable space hides the problem.

    Source: USP General Chapter <797> Pharmaceutical Compounding — Sterile Preparations, monitoring of pressure differentials and response to out-of-specification conditionsReport a problem with this question

17. 17. How does non-viable particle counting differ from viable air sampling?

    • A.Particle counting is done on surfaces, while viable sampling is done only within room air.
    • B.Particle counting names the species present, while viable sampling gives only a total count.
    • C.Particle counting measures particulate burden, while viable sampling recovers organisms that grow.✓ Answer
    • D.Particle counting recovers living organisms, while viable sampling reports total particulate.

    A particle counter reports everything suspended in the air regardless of whether it is alive, and it is how ISO classification is verified. Viable sampling draws air onto a growth medium so that organisms capable of multiplying are recovered and counted; the two tests answer different questions and neither substitutes for the other.

    Source: USP General Chapter <797> Pharmaceutical Compounding — Sterile Preparations, environmental monitoring of air qualityReport a problem with this question

18. 18. A technician must take a surface sample from a curved, irregular surface inside a primary engineering control. Which method is appropriate?

    • A.Use a sterile swab, because a contact plate cannot make even contact with an irregular shape.✓ Answer
    • B.Set an open settle plate beside the surface for the duration of the compounding session.
    • C.Press a contact plate against the flattest nearby surface and record it as the curved one.
    • D.Press a contact plate firmly and rock it, because swabs cannot recover organisms reliably.

    Contact plates work by pressing a raised agar surface evenly against a flat area, so on curved or irregular geometry much of the site never touches the medium and the result understates what is there. A sterile swab reaches the actual site; sampling a different surface instead does not tell you about the one in question, and after any sampling the residual medium is cleaned off and the surface disinfected.

    Source: USP General Chapter <797> Pharmaceutical Compounding — Sterile Preparations, surface sampling technique and sample sitesReport a problem with this question

19. 19. Environmental monitoring samples are collected Friday evening and left on an anteroom shelf until Monday. Why is this unacceptable?

    • A.The plates must be frozen before shipping or the testing laboratory will reject them.
    • B.The plates must be counted within the same shift because colonies cannot be counted later.
    • C.The plates must be incubated under controlled conditions or organisms present may not grow.✓ Answer
    • D.The plates must be refrigerated until read or the growth medium dries and becomes unusable.

    Recovery depends on holding the medium at defined temperatures for defined periods, so samples left at ambient conditions may never grow what they actually captured and will read as falsely acceptable. Samples go promptly into an incubator, or are shipped promptly to the laboratory protected from temperature and humidity extremes.

    Source: USP General Chapter <797> Pharmaceutical Compounding — Sterile Preparations, incubation and handling of environmental monitoring samplesReport a problem with this question

20. 20. A viable air sample taken in the buffer room exceeds the action level. What does that result mean for the pharmacy?

    • A.The source must be investigated and corrected; the count alone does not condemn a preparation.✓ Answer
    • B.The result may be set aside if the next round of sampling falls back within the action level.
    • C.The room is reclassified to the next lower classification until the following sampling round.
    • D.Every preparation made since the previous sampling round is automatically considered adulterated.

    Action levels are thresholds for response, not sterility specifications, so exceeding one starts an investigation into the source, corrective action such as re-cleaning with a sporicidal agent, and re-sampling to confirm the fix worked. The pharmacist evaluates whether any preparations are affected and may quarantine or discard them; simply repeating the sample until it passes is not an investigation.

    Source: USP General Chapter <797> Pharmaceutical Compounding — Sterile Preparations, action levels and corrective actionReport a problem with this question

21. 21. An environmental monitoring result exceeds an action level. What identification step is expected as part of the response?

    • A.Identification is needed only when the organism is recovered from the anteroom floor surface.
    • B.The recovered organism is identified to the strain level by genetic sequencing in every case.
    • C.The recovered organism is identified at least to the genus level to guide corrective action.✓ Answer
    • D.No identification is needed, because the colony count alone determines the corrective action.

    Knowing what grew points to where it came from: skin flora suggests personnel or garbing technique, mold suggests moisture or construction, and gram-negative organisms suggest water sources or sinks. Because the corrective plan depends on both the count and the identity, identification at least to genus is the minimum expected whenever an action level is exceeded.

    Source: USP General Chapter <797> Pharmaceutical Compounding — Sterile Preparations, investigation of results exceeding action levelsReport a problem with this question

22. 22. Surface samples inside the workbench repeatedly exceed the action level while viable air samples in the room stay acceptable. Which cause best explains this pattern?

    • A.The pressure differential between the buffer room and the anteroom has been lost overnight.
    • B.The room's air change rate has drifted below the rate the facility's procedures specify.
    • C.A leak has developed in the medium of the ceiling HEPA filter serving the buffer room.
    • D.Items are being carried into the workbench without their outer surfaces being disinfected.✓ Answer

    A facility air problem — a filter leak, low air exchange, or a lost pressure differential — would degrade the air samples and particle counts as well, so contamination confined to surfaces inside the primary engineering control points instead to what is being introduced or to technique. Undisinfected packaging, objects set down in the airflow and touch contamination are the usual explanations, and the investigation should follow the pattern the data shows.

    Source: USP General Chapter <797> Pharmaceutical Compounding — Sterile Preparations, investigating causes of out-of-specification environmental resultsReport a problem with this question

Practice questions based on the PTCB CSPT Content Outline and the USP General Chapters governing sterile compounding. CSPT and PTCB are marks of the Pharmacy Technician Certification Board; this site is not affiliated with or endorsed by PTCB or USP. Standards for sterile compounding are revised periodically and your state board of pharmacy and your employer's policies also apply — always follow your facility's current procedures and confirm current requirements before testing. About the CSPT exam →