MIBoK Practice Exam Questions And

Machinery Inspection Certification (MIBoK) Practice Exam Questions And Correct Answers (Verified Answers) Plus Rationales 2026 Q&A | Instant Download Pdf

• What is the primary purpose of vibration analysis in machinery

inspection?

• To measure temperature
• To detect mechanical imbalances
• To monitor electrical efficiency
• To assess lubrication levels

Answer: B) To detect mechanical imbalances

Rationale: Vibration analysis identifies abnormal vibrations caused by

mechanical imbalances, misalignment, looseness, or bearing defects, which helps prevent machinery failures. 1 / 4

• Which of the following is the most critical factor in selecting inspection

intervals for rotating machinery?

• Manufacturer recommendations
• Cost of downtime
• Machinery criticality and operating conditions
• Operator preference

Answer: C) Machinery criticality and operating conditions

Rationale: Inspection intervals should be based on how critical the

machinery is to operations and the conditions it operates under, ensuring reliability and safety.

• Thermography in machinery inspection primarily detects issues related

to:

• Mechanical wear
• Electrical hotspots
• Vibration resonance
• Fluid contamination

Answer: B) Electrical hotspots

Rationale: Infrared thermography identifies excessive heat in electrical

components, motors, and connections, often indicative of faults or overloads. 2 / 4

• Which type of inspection requires machinery shutdown for a detailed

internal examination?

• Non-destructive testing (NDT)
• Condition monitoring
• Predictive inspection
• Routine operational checks

Answer: A) Non-destructive testing (NDT)

Rationale: Certain NDT methods, such as ultrasonic or radiographic

inspections, often require shutdown to examine internal components safely.

5. Lubrication analysis helps in identifying:

• Bearing misalignment
• Gear wear and contamination
• Structural cracks
• Electrical insulation breakdown

Answer: B) Gear wear and contamination

Rationale: Lubrication analysis detects metal particles, water, or other

contaminants in oil, indicating wear or degradation of machinery components.

• / 4

• What is the acceptable vibration velocity range for most standard

industrial rotating machinery?

• 0–2 mm/s
• 2–4 mm/s
• 4–8 mm/s
• 8–12 mm/s

Answer: B) 2–4 mm/s

Rationale: A vibration velocity of 2–4 mm/s is generally acceptable for well-

maintained industrial machinery; higher values may indicate imbalance or misalignment.

• What is the primary benefit of using ultrasonic testing in machinery

inspection?

• It detects surface corrosion
• It measures electrical efficiency
• It detects internal flaws before failure
• It lubricates bearings automatically

Answer: C) It detects internal flaws before failure

Rationale: Ultrasonic testing uses high-frequency sound waves to detect

internal cracks, voids, or delaminations in components before catastrophic failure occurs.

• / 4