Oxygen Tank Duration
Oxygen tank duration calculation approximates how much time is left in an oxygen tank based on oxygen flow settings.
Duration of Flow = Oxygen Tank Conversion Factor * Remaining Tank Pressure (psi) / Continuous Flow Rate (L/min)
Oxygen Cylinder Conversion Factors
• D Tank = 0.16
• E Tank = 0.28
• G Tank = 2.41
• H/K Tank = 3.14
• M tank = 1.56
Duration of Flow
Oxygen Duration Exam Questions
1. A size D cylinder of oxygen has a remaining pressure of 1200 psi. The patient’s flow rate is 3 L/min. When will the tank be completely empty?
A. 45 min
B. 1 hour 19 min
C. 1 hour 5 min
D. 1 hour 30 min
2. A size G cylinder of oxygen has a remaining pressure of 2000 psi. The patient’s flow rate is 10 L/min. When will the tank be completely empty?
A. 10 hours 10 min
B. 9 hours 8 min
C. 8 hours 2 min
D. 5 hours
3. Correctly match the Oxygen cylinder conversion factor to correct tank size.
A. D tank = 3.14, E tank = 0.28, G tank = 2.41, H tank = 0.16
B. D tank = 0.16, E tank = 0.28, G tank = 2.41, H tank = 3.14
C. D tank = 0.28, E tank = 0.16, G tank = 3.14, H tank = 2.41
D. D tank = 0.16, E tank = 2.41, G tank = 0.28, H tank = 3.14
4. A patient states his E tank cylinder only lasted 1 hour at a flow rate of 2LPM. What psi of oxygen was in his tank?
A. 1000 psi
B. 378 psi
C. 429 psi
D. 1240 psi
Liquid Oxygen Duration Test Questions:
- Duration: Oxygen remaining in liquid O2 cylinder in min
- Capacity: Liquid O2 in cylinder in L
- Factor to convert liquid to gaseous O2
- Reading on cylinder (example 0.33)
- Flow: O2 flow rate L/min
1. The liquid capacity of a home liquid oxygen system is 40 Litres. The home care patient uses the system for 8 hours during sleep at a flow of 3 L/min. How many days with the home oxygen system last?
A. 24 days
B. 29 days
C. 42 days
D. 12 days
2. If the capacity of a liquid oxygen cylinder in 4.0 L and the reading on the gauge is ⅓ full. How long with the liquid oxygen last if the flow is at 2 L/min.
A. 567 min
B. 766 min
C. 340 min
D. 102 min