NBRC MOCK TMC EXAM 2026/2027 QUESTIONS
AND CORRECT ANSWERS GRADED A+
The respiratory therapist receives an order to set up a moderate level of O2 on a
patient who arrives in the ED breathing at a rate of 35 breaths/min. Which of the
following O2 delivery devices is most appropriate to use in this situation?
A. Simple O2 mask at 10 L/min
B. Nasal cannula at 4 L/min
C. NRB Mask at 15 L/min
D. Air-entrainment mask at 40% O2
D. Air-entrainment mask at 40% O2
A severe COPD patient arrives in the emergency department on a 2 L/min nasal
cannula. Arterial blood gas results follow:
pH: 7.32
PaCO2: 67 mmHg
PaO2: 62 mmHg
HCO3: 38 mEq/L
Which of the following is the most appropriate recommendation?
A. Increase the liter flow to 4 L/min
,B. Maintain the current O2 level
C. Institute noninvasive positive pressure ventilation (NPPV)
D. Place on a NRB mask at 12 L/min
B. Maintain the current O2 level
The physician has ordered O2 to be set up on a patient who has a spontaneous tidal
volume of 500 mL and an inspiratory time of 1 second. Which of the following O2
delivery devices will deliver a flow that meets or exceeds this patient's inspiratory
flow?
A. 35% air-entrainment mask at 6 L/min
B. 60% aerosol mask at 12 L/min
C. NRB mask at 15 L/min
D. Simple O2 mask at 10 L/min
500 mL = 0.5 L
0.5/1 = 0.5 L/s (change L/s to ?/min by multiplying by 60
0.5 L x 60= 30 L/min
Select the device that delivers a flow of at least 30L/min
A. 35% air-entrainment mask at 6 L/min
A patient breathing 50% oxygen has a PaO2 of 248 torr. Which of the following
should the RT recommend?
A. Discontinue O2 therapy
, B. Decrease the oxygen to 30%
C. Titrate oxygen to maintain an SpO2 > 93%
D. Repeat the blood gases because the PaO2 is not possible on this FiO2.
C. Titrate oxygen to maintain an SpO2 > 93%
Explanation: A PaO2 of 250 torr is normal on 50% O2. Remember, to determine
the normal PaO2 on any given O2%, multiply the O2% by 5. This is an
approximation. If titrate was not a choice, then you would discontinue the oxygen.
A patient is receiving 30% oxygen via an air-entrainment mask at a flow of 5
L/min. The total flow delivered by this device is which of the following?
A. 36 L/min
B. 45 L/min
C. 54 L/min
D. 60 L/min
(*Use 21 with O2 % less than 40%)
(100- 30%)/ (30%-*21) = 70/9 = 8/1 or 8:1 ratio
8+1= 9
9x5 = 45 L/min
B. 45 L/min
A patient is receiving O2 from an E cylinder at 4 L/min through a nasal cannula.
The cylinder pressure is 1900 psig. How long will the cylinder run until it is
empty?
AND CORRECT ANSWERS GRADED A+
The respiratory therapist receives an order to set up a moderate level of O2 on a
patient who arrives in the ED breathing at a rate of 35 breaths/min. Which of the
following O2 delivery devices is most appropriate to use in this situation?
A. Simple O2 mask at 10 L/min
B. Nasal cannula at 4 L/min
C. NRB Mask at 15 L/min
D. Air-entrainment mask at 40% O2
D. Air-entrainment mask at 40% O2
A severe COPD patient arrives in the emergency department on a 2 L/min nasal
cannula. Arterial blood gas results follow:
pH: 7.32
PaCO2: 67 mmHg
PaO2: 62 mmHg
HCO3: 38 mEq/L
Which of the following is the most appropriate recommendation?
A. Increase the liter flow to 4 L/min
,B. Maintain the current O2 level
C. Institute noninvasive positive pressure ventilation (NPPV)
D. Place on a NRB mask at 12 L/min
B. Maintain the current O2 level
The physician has ordered O2 to be set up on a patient who has a spontaneous tidal
volume of 500 mL and an inspiratory time of 1 second. Which of the following O2
delivery devices will deliver a flow that meets or exceeds this patient's inspiratory
flow?
A. 35% air-entrainment mask at 6 L/min
B. 60% aerosol mask at 12 L/min
C. NRB mask at 15 L/min
D. Simple O2 mask at 10 L/min
500 mL = 0.5 L
0.5/1 = 0.5 L/s (change L/s to ?/min by multiplying by 60
0.5 L x 60= 30 L/min
Select the device that delivers a flow of at least 30L/min
A. 35% air-entrainment mask at 6 L/min
A patient breathing 50% oxygen has a PaO2 of 248 torr. Which of the following
should the RT recommend?
A. Discontinue O2 therapy
, B. Decrease the oxygen to 30%
C. Titrate oxygen to maintain an SpO2 > 93%
D. Repeat the blood gases because the PaO2 is not possible on this FiO2.
C. Titrate oxygen to maintain an SpO2 > 93%
Explanation: A PaO2 of 250 torr is normal on 50% O2. Remember, to determine
the normal PaO2 on any given O2%, multiply the O2% by 5. This is an
approximation. If titrate was not a choice, then you would discontinue the oxygen.
A patient is receiving 30% oxygen via an air-entrainment mask at a flow of 5
L/min. The total flow delivered by this device is which of the following?
A. 36 L/min
B. 45 L/min
C. 54 L/min
D. 60 L/min
(*Use 21 with O2 % less than 40%)
(100- 30%)/ (30%-*21) = 70/9 = 8/1 or 8:1 ratio
8+1= 9
9x5 = 45 L/min
B. 45 L/min
A patient is receiving O2 from an E cylinder at 4 L/min through a nasal cannula.
The cylinder pressure is 1900 psig. How long will the cylinder run until it is
empty?
