10 exam-style questions with answers and explanations, straight from our 1,030-question bank. Tap an answer to check yourself. When you're ready, take the scored version in the free practice test.
The MGI 6020 exam has 40 questions and runs 2 hours.
Question 1
A new recovery suite has 21 in. Hg vacuum at its inlets with no test flow. Drawing 85 normal L/min at one inlet reduces an adjacent inlet on the same branch to 9 in. Hg vacuum. During the draw, the source stays at 22 in. Hg vacuum and another branch stays at 18 in. Hg vacuum. The affected branch passed its isolated leakage test, and the gauges have been checked against a reference. Which fault best fits these findings?
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Correct answer: B - Excessive flow resistance in the affected distribution branch
Question 2
Before a crew heats a copper-to-copper joint in new oxygen piping that has not been connected to an existing system, an inspector reviews the setup. The brazer and procedure qualifications are current, and the joint was cleaned two hours earlier. Which recorded condition must be corrected before brazing begins?
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Correct answer: D - The oxygen analyzer reads 1.4% oxygen in the purged piping.
Question 3
For a pressure-differential cross-connection test, the oxygen piping is charged with nitrogen NF at 50 psig and the medical-air piping with nitrogen NF at 60 psig. The verified source settings remain stable. Using the correct gas-specific adapters and calibrated gauges, the verifier finds 60 psig at an oxygen-labeled outlet and 50 psig at the adjacent medical-air outlet. What does this result establish?
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Correct answer: A - The two terminal connections do not correspond to their designated piping services.
Question 4
After substantial use, a nitrous oxide cylinder has lost weight but shows nearly the same cylinder pressure. An oxygen cylinder used over the same period shows a lower cylinder pressure. Both cylinders have returned to the same room temperature, their gauges function correctly, and liquid remains in the nitrous oxide cylinder. Why are the pressure trends different?
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Correct answer: C - Liquid nitrous oxide replenishes the vapor, maintaining pressure at that temperature.
Question 5
A contractor offers an employee from its separate quality-assurance department to perform the independent verification of piping the contractor installed. The employee holds a current ASSE 6030 certification and did not install or supervise the work. Does this arrangement satisfy the independence requirement?
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Correct answer: D - No; the verifier must be independent of the contractor performing this installation.
Question 6
A material submittal specifies hard-drawn ASTM B819 Type L copper for a 50-psig oxygen line and hard-drawn ASTM B88 Type M copper for a medical-surgical vacuum line operating at 20 in. Hg vacuum. Both are new, aboveground installations. Oxygen-service cleanliness is documented, and the vacuum tubing is clearly segregated and identified before installation. Under NFPA 99 (2024), what change is required to this tubing selection?
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Correct answer: B - No change; each specified tube is permitted for its assigned service.
Question 7
A Category 1 medical-air source has three compressors rated at 70, 50, and 40 SCFM at the specified operating conditions. Peak calculated demand is 85 SCFM. The treatment equipment and controls satisfy their separate redundancy requirements. Which assessment correctly applies the compressor-capacity requirement?
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Correct answer: C - Accept; 90 SCFM remains with the 70-SCFM compressor out of service.
Question 8
A small outpatient pediatric center uses piped gases for ventilatory support. Its documented assessment finds that failure of this support is likely to cause major injury or death. The designer argues that an outpatient building cannot require the highest medical-gas risk category. Which NFPA 99 category matches the documented consequence?
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Correct answer: A - Category 1
Question 9
An isolated nitrogen support-gas pipeline has a normal operating pressure of 180 psig. For the installer's initial pressure test, the test plan specifies 216 psig, borrowing the pressure from the later 24-hour standing test. The source valve is closed, and components vulnerable to the initial test pressure have been excluded. What pressure belongs in the initial-test plan under NFPA 99 (2024)?
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Correct answer: A - 270 psig, applying the initial-test requirement to the 180-psig operating pressure
Question 10
An approved concentrator installation is designated and labeled for Oxygen 93 USP. A calibrated analyzer measures 94.2% oxygen at the source and at a representative outlet. All separately required contaminant tests are satisfactory. A reviewer rejects the concentration results solely because they are below 99%. How should this finding be resolved?
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Correct answer: D - Accept the concentration results; 94.2% is within the Oxygen 93 USP range.
What's on the MGI 6020 exam
The Medical Gas Inspector 6020 (MGI 6020) exam is organized into 1 knowledge domains. These free practice questions are drawn from across them so you can see where you're strong and where to study:
Medical Gas Inspection, Standards, Codes and System Verification
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