TB Test Infection Control and Prevention 2 — Questions and Answers
Question 1: What does HEPA stand for in the context of air filtration systems used for TB infection control?
- High-Efficiency Pathogen Arrest
- High-Efficiency Particulate Air (Correct answer)
- Healthcare Environmental Protection Apparatus
- Hazardous Exposure Prevention Airflow
Correct answer: High-Efficiency Particulate Air
HEPA stands for High-Efficiency Particulate Air; HEPA filters remove at least 99.97% of airborne particles ≥0.3 microns, effectively capturing M. tuberculosis droplet nuclei.
Question 2: Where should upper-room ultraviolet germicidal irradiation (UVGI) fixtures be positioned to be most effective in reducing airborne M. tuberculosis?
- At floor level to disinfect settling particles
- In the upper zone of the room where air convects before recirculating downward (Correct answer)
- Inside supply air ducts to sterilize incoming air
- Directly above patient beds to disinfect the breathing zone
Correct answer: In the upper zone of the room where air convects before recirculating downward
Upper-room UVGI fixtures are placed in the upper zone so that naturally convecting room air passes through the UV field, killing M. tuberculosis before the air recirculates to the occupied lower zone.
Question 3: According to the CDC/NIOSH hierarchy of controls for TB, which level must be implemented FIRST before other controls can be effective?
- Personal protective equipment (N95 respirators)
- Administrative controls (infection control policies and procedures) (Correct answer)
- Engineering controls (negative pressure rooms, HEPA filtration)
- Environmental controls (UV lights, surface disinfection)
Correct answer: Administrative controls (infection control policies and procedures)
Administrative controls establish the policies, protocols, and training that govern how engineering controls and PPE are used; without them, lower-level controls cannot be implemented effectively.
Question 4: What does the term 'source control' refer to in the context of TB infection control?
- Using HEPA filtration to remove TB bacteria from recirculated air
- Applying negative pressure to prevent infectious air from leaving the isolation room
- Having the infectious patient wear a surgical mask to reduce release of droplet nuclei (Correct answer)
- Administering antibiotics to reduce the patient's bacterial burden and infectiousness
Correct answer: Having the infectious patient wear a surgical mask to reduce release of droplet nuclei
Source control refers to measures applied directly to the infectious person—such as placing a surgical mask on the patient—to reduce the release of M. tuberculosis droplet nuclei at the point of origin.
Question 5: A patient with suspected pulmonary TB presents to an emergency department that has no airborne infection isolation room available. Which immediate measure is MOST appropriate?
- Place the patient in a standard room with the door closed and open the window
- Move the patient to a hallway away from other patients
- Place a surgical mask on the patient and separate them from others in a designated area (Correct answer)
- Immediately administer TB medications to reduce infectiousness
Correct answer: Place a surgical mask on the patient and separate them from others in a designated area
Placing a surgical mask on the patient (source control) and separating them from others limits droplet nuclei release and exposure until a proper AIIR becomes available.
Question 6: How often must healthcare workers who use N95 respirators for TB patient care undergo respirator fit testing, per OSHA requirements?
- At initial hire only unless facial features change significantly
- Every 6 months
- Annually, and whenever respirator model or facial features change (Correct answer)
- Every 2 years
Correct answer: Annually, and whenever respirator model or facial features change
OSHA's Respiratory Protection Standard (29 CFR 1910.134) requires annual fit testing for tight-fitting respirators, plus retesting whenever a different respirator model is used or the worker's facial features change.
Question 7: Which statement correctly distinguishes a surgical mask from an N95 respirator in TB infection control?
- Both provide equivalent protection against inhaling TB droplet nuclei
- Surgical masks filter droplet nuclei for the wearer; N95s only protect from splashes
- Surgical masks are used for patient source control; N95 respirators protect healthcare workers from inhalation (Correct answer)
- N95 respirators should be worn by both patient and healthcare worker in all TB situations
Correct answer: Surgical masks are used for patient source control; N95 respirators protect healthcare workers from inhalation
Surgical masks are used for source control worn by the patient to reduce droplet nuclei release, while N95 respirators are required for healthcare workers to protect against inhaling airborne particles.
TB Test Infection Control and Prevention 2
What does HEPA stand for in the context of air filtration systems used for TB infection control?