Arizona Certified Reliability Engineer
(CRE) Exam Practice Questions And
Correct Answers (Verified Answers) Plus
Rationale 2026 Q&A| Instant Download
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1. Which of the following best describes the primary objective of
reliability engineering within asset-intensive industries?
A. To maximize production output regardless of equipment condition
B. To ensure systems perform their required function under stated
conditions for a defined period of time
C. To reduce labor costs by minimizing preventive maintenance
D. To eliminate all equipment failures permanently
The primary goal of reliability engineering is to ensure that systems
and components reliably perform their intended function within
specified conditions and timeframes, focusing on performance rather
than cost or output alone.
2. A system has exponential failure behavior with a constant failure rate
λ = 0.002 failures per hour. What is the reliability at 500 hours?
A. 0.3679
B. 0.6065
C. 0.1353
D. 0.2231
For exponential failure distributions, reliability R(t) = e^(−λt).
Substituting λ=0.002 and t=500 yields R(t)=e^(−1)=0.3679.
,3. Which analysis technique uses functional block diagrams to determine
all combinations of basic events that can cause the top undesired
event?
A. Failure Modes and Effects Analysis (FMEA)
B. Fault Tree Analysis (FTA)
C. Root Cause Analysis (RCA)
D. Life Data Analysis (LDA)
Fault Tree Analysis deconstructs an undesired top event into logical
combinations of basic events using AND/OR gates to identify failure
pathways.
4. If a repairable component has an MTBF of 1000 hours and an MTTR of
10 hours, what is its availability?
A. 0.50
B. 0.75
C. 0.99
D. 0.91
Availability A = MTBF / (MTBF + MTTR) = 1000 / (1000 + 10) = 0.99,
reflecting high uptime for low repair times.
5. Which term best describes the probability that a component will
perform without failure for a specified period under stated
conditions?
A. Maintainability
B. Reliability
C. Availability
D. Risk
Reliability specifically refers to the probability of failure-free
performance over a defined time and conditions.
6. In FMEA, what does the Risk Priority Number (RPN) represent?
A. The cost of corrective action
B. The time to repair the failure mode
C. The product of severity, occurrence, and detection ratings
D. The total number of failure modes identified
RPN is calculated as Severity × Occurrence × Detection to prioritize
high-risk failure modes for action.
, 7. A bathtub curve typically demonstrates which failure rate pattern?
A. Constant throughout the life of the product
B. Increasing then decreasing
C. High infant mortality, constant random failures, increasing
wear-out
D. Decreasing wear-in only
The bathtub curve displays an early high failure rate due to infant
mortality, a flat random failure region, and an increasing failure rate
as wear-out begins.
8. What statistical distribution is most appropriate for modeling
time-to-failure data with a constant failure rate?
A. Normal distribution
B. Weibull with β > 1
C. Exponential distribution
D. Lognormal distribution
The exponential distribution models a constant failure rate (β=1 in
Weibull), making it suitable for random failures.
9. In reliability block diagrams, what does a series configuration imply
about system reliability?
A. The system reliability is the maximum of component reliabilities
B. The system reliability is the product of component reliabilities
C. The system reliability is unaffected by individual components
D. The system reliability is the sum of component reliabilities
A series system requires all components to function; system
reliability equals the product of individual reliabilities.
10. Which reliability growth model assumes that failure rate
decreases exponentially with cumulative testing time?
A. Crow-AMSAA Model
B. Weibull Growth Model
C. Duane Model
D. Shock Model
The Duane model characterizes reliability improvement as an
exponential decline in failure intensity with cumulative test time.
11. What is the primary purpose of an accelerated life test (ALT)?
A. To delay failures for warranty analysis
(CRE) Exam Practice Questions And
Correct Answers (Verified Answers) Plus
Rationale 2026 Q&A| Instant Download
1. Which of the following best describes the primary objective of
reliability engineering within asset-intensive industries?
A. To maximize production output regardless of equipment condition
B. To ensure systems perform their required function under stated
conditions for a defined period of time
C. To reduce labor costs by minimizing preventive maintenance
D. To eliminate all equipment failures permanently
The primary goal of reliability engineering is to ensure that systems
and components reliably perform their intended function within
specified conditions and timeframes, focusing on performance rather
than cost or output alone.
2. A system has exponential failure behavior with a constant failure rate
λ = 0.002 failures per hour. What is the reliability at 500 hours?
A. 0.3679
B. 0.6065
C. 0.1353
D. 0.2231
For exponential failure distributions, reliability R(t) = e^(−λt).
Substituting λ=0.002 and t=500 yields R(t)=e^(−1)=0.3679.
,3. Which analysis technique uses functional block diagrams to determine
all combinations of basic events that can cause the top undesired
event?
A. Failure Modes and Effects Analysis (FMEA)
B. Fault Tree Analysis (FTA)
C. Root Cause Analysis (RCA)
D. Life Data Analysis (LDA)
Fault Tree Analysis deconstructs an undesired top event into logical
combinations of basic events using AND/OR gates to identify failure
pathways.
4. If a repairable component has an MTBF of 1000 hours and an MTTR of
10 hours, what is its availability?
A. 0.50
B. 0.75
C. 0.99
D. 0.91
Availability A = MTBF / (MTBF + MTTR) = 1000 / (1000 + 10) = 0.99,
reflecting high uptime for low repair times.
5. Which term best describes the probability that a component will
perform without failure for a specified period under stated
conditions?
A. Maintainability
B. Reliability
C. Availability
D. Risk
Reliability specifically refers to the probability of failure-free
performance over a defined time and conditions.
6. In FMEA, what does the Risk Priority Number (RPN) represent?
A. The cost of corrective action
B. The time to repair the failure mode
C. The product of severity, occurrence, and detection ratings
D. The total number of failure modes identified
RPN is calculated as Severity × Occurrence × Detection to prioritize
high-risk failure modes for action.
, 7. A bathtub curve typically demonstrates which failure rate pattern?
A. Constant throughout the life of the product
B. Increasing then decreasing
C. High infant mortality, constant random failures, increasing
wear-out
D. Decreasing wear-in only
The bathtub curve displays an early high failure rate due to infant
mortality, a flat random failure region, and an increasing failure rate
as wear-out begins.
8. What statistical distribution is most appropriate for modeling
time-to-failure data with a constant failure rate?
A. Normal distribution
B. Weibull with β > 1
C. Exponential distribution
D. Lognormal distribution
The exponential distribution models a constant failure rate (β=1 in
Weibull), making it suitable for random failures.
9. In reliability block diagrams, what does a series configuration imply
about system reliability?
A. The system reliability is the maximum of component reliabilities
B. The system reliability is the product of component reliabilities
C. The system reliability is unaffected by individual components
D. The system reliability is the sum of component reliabilities
A series system requires all components to function; system
reliability equals the product of individual reliabilities.
10. Which reliability growth model assumes that failure rate
decreases exponentially with cumulative testing time?
A. Crow-AMSAA Model
B. Weibull Growth Model
C. Duane Model
D. Shock Model
The Duane model characterizes reliability improvement as an
exponential decline in failure intensity with cumulative test time.
11. What is the primary purpose of an accelerated life test (ALT)?
A. To delay failures for warranty analysis
