NBRC TMC Examination CRT RRT Credentialing Question
Bank (Latest 2026/2027 Edition) – 100% Correct Questions,
Answers & Detailed Rationales
Total Questions: 70
Time Allowed: 90 Minutes (Practice Exam)
Passing Score: Low Cut = CRT; High Cut = RRT Eligibility
Instructions: Select the BEST answer for each question based on respiratory care
principles, NBRC clinical standards, and evidence-based practice. Pay careful attention
to qualifying words (INITIALLY, FIRST, SHOULD, MOST, LEAST) and select the single best
response for each question.
SECTION 1: PATIENT DATA EVALUATION AND RECOMMENDATIONS
(35–40%)
Questions 1–26
Question 1 (Recall)
Normal arterial blood gas values for a healthy adult breathing room air at sea level
include which of the following?
A. pH 7.30, PaCO₂ 50 mmHg, PaO₂ 60 mmHg
,B. pH 7.40, PaCO₂ 40 mmHg, PaO₂ 90 mmHg
C. pH 7.50, PaCO₂ 30 mmHg, PaO₂ 100 mmHg
D. pH 7.35, PaCO₂ 50 mmHg, PaO₂ 70 mmHg
Correct Answer: B
Rationale: Normal ABG values are pH 7.35–7.45, PaCO₂ 35–45 mmHg, and PaO₂
80–100 mmHg on room air (FiO₂ 0.21) at sea level. Option B represents the classic
normal values. Option A reflects respiratory acidosis with hypoxemia; option C reflects
respiratory alkalosis; option D reflects respiratory acidosis.
Question 2 (Recall)
Which pulmonary function test parameter is MOST useful for differentiating obstructive
from restrictive lung disease?
A. Total lung capacity (TLC)
B. Forced expiratory volume in 1 second (FEV₁)
C. FEV₁/FVC ratio
D. Residual volume (RV)
Correct Answer: C
Rationale: The FEV₁/FVC ratio is the primary differentiator. In obstructive disease, the
ratio is decreased (< 0.70). In restrictive disease, both FEV₁ and FVC are proportionally
decreased, so the ratio is normal or increased. TLC and RV help classify severity and
identify air trapping but the FEV₁/FVC ratio is the key diagnostic discriminator.
,Question 3 (Recall)
The normal range for central venous pressure (CVP) is:
A. 0–5 mmHg
B. 2–6 mmHg
C. 8–12 mmHg
D. 15–20 mmHg
Correct Answer: B
Rationale: Normal CVP is 2–6 mmHg, reflecting right ventricular preload and venous
return. Values > 6 mmHg suggest volume overload or right ventricular dysfunction.
Pulmonary capillary wedge pressure (PCWP), reflecting left atrial pressure, is normally
6–12 mmHg. Systemic arterial pressures are much higher.
Question 4 (Recall)
Anatomic dead space is defined as:
A. The volume of gas that remains in the lungs at end-expiration
B. The volume of the conducting airways where no gas exchange occurs
C. The volume of alveoli that are ventilated but not perfused
D. The total volume of gas moved in one minute
Correct Answer: B
, Rationale: Anatomic dead space (approximately 1 mL/lb or 2.2 mL/kg) is the volume of
the conducting airways (nose, pharynx, larynx, trachea, bronchi) where gas does not
come into contact with alveolar-capillary membranes. Alveolar dead space (ventilated
but not perfused alveoli) plus anatomic dead space equals physiologic dead space.
Question 5 (Recall)
Normal adult vital capacity (VC) is approximately:
A. 1–2 L
B. 2–3 L
C. 4–5 L
D. 6–7 L
Correct Answer: C
Rationale: Normal VC is approximately 65–75 mL/kg ideal body weight, yielding about
4–5 L for an average-sized adult. VC is the sum of inspiratory capacity and expiratory
reserve volume. Values significantly below predicted indicate restrictive pathology,
neuromuscular weakness, or poor effort.
Question 6 (Recall)
Physiologic shunt refers to:
A. Alveoli that are ventilated but not perfused
B. Alveoli that are perfused but not ventilated
C. Gas trapped in the conducting airways
Bank (Latest 2026/2027 Edition) – 100% Correct Questions,
Answers & Detailed Rationales
Total Questions: 70
Time Allowed: 90 Minutes (Practice Exam)
Passing Score: Low Cut = CRT; High Cut = RRT Eligibility
Instructions: Select the BEST answer for each question based on respiratory care
principles, NBRC clinical standards, and evidence-based practice. Pay careful attention
to qualifying words (INITIALLY, FIRST, SHOULD, MOST, LEAST) and select the single best
response for each question.
SECTION 1: PATIENT DATA EVALUATION AND RECOMMENDATIONS
(35–40%)
Questions 1–26
Question 1 (Recall)
Normal arterial blood gas values for a healthy adult breathing room air at sea level
include which of the following?
A. pH 7.30, PaCO₂ 50 mmHg, PaO₂ 60 mmHg
,B. pH 7.40, PaCO₂ 40 mmHg, PaO₂ 90 mmHg
C. pH 7.50, PaCO₂ 30 mmHg, PaO₂ 100 mmHg
D. pH 7.35, PaCO₂ 50 mmHg, PaO₂ 70 mmHg
Correct Answer: B
Rationale: Normal ABG values are pH 7.35–7.45, PaCO₂ 35–45 mmHg, and PaO₂
80–100 mmHg on room air (FiO₂ 0.21) at sea level. Option B represents the classic
normal values. Option A reflects respiratory acidosis with hypoxemia; option C reflects
respiratory alkalosis; option D reflects respiratory acidosis.
Question 2 (Recall)
Which pulmonary function test parameter is MOST useful for differentiating obstructive
from restrictive lung disease?
A. Total lung capacity (TLC)
B. Forced expiratory volume in 1 second (FEV₁)
C. FEV₁/FVC ratio
D. Residual volume (RV)
Correct Answer: C
Rationale: The FEV₁/FVC ratio is the primary differentiator. In obstructive disease, the
ratio is decreased (< 0.70). In restrictive disease, both FEV₁ and FVC are proportionally
decreased, so the ratio is normal or increased. TLC and RV help classify severity and
identify air trapping but the FEV₁/FVC ratio is the key diagnostic discriminator.
,Question 3 (Recall)
The normal range for central venous pressure (CVP) is:
A. 0–5 mmHg
B. 2–6 mmHg
C. 8–12 mmHg
D. 15–20 mmHg
Correct Answer: B
Rationale: Normal CVP is 2–6 mmHg, reflecting right ventricular preload and venous
return. Values > 6 mmHg suggest volume overload or right ventricular dysfunction.
Pulmonary capillary wedge pressure (PCWP), reflecting left atrial pressure, is normally
6–12 mmHg. Systemic arterial pressures are much higher.
Question 4 (Recall)
Anatomic dead space is defined as:
A. The volume of gas that remains in the lungs at end-expiration
B. The volume of the conducting airways where no gas exchange occurs
C. The volume of alveoli that are ventilated but not perfused
D. The total volume of gas moved in one minute
Correct Answer: B
, Rationale: Anatomic dead space (approximately 1 mL/lb or 2.2 mL/kg) is the volume of
the conducting airways (nose, pharynx, larynx, trachea, bronchi) where gas does not
come into contact with alveolar-capillary membranes. Alveolar dead space (ventilated
but not perfused alveoli) plus anatomic dead space equals physiologic dead space.
Question 5 (Recall)
Normal adult vital capacity (VC) is approximately:
A. 1–2 L
B. 2–3 L
C. 4–5 L
D. 6–7 L
Correct Answer: C
Rationale: Normal VC is approximately 65–75 mL/kg ideal body weight, yielding about
4–5 L for an average-sized adult. VC is the sum of inspiratory capacity and expiratory
reserve volume. Values significantly below predicted indicate restrictive pathology,
neuromuscular weakness, or poor effort.
Question 6 (Recall)
Physiologic shunt refers to:
A. Alveoli that are ventilated but not perfused
B. Alveoli that are perfused but not ventilated
C. Gas trapped in the conducting airways
