Documentation and Reporting Flashcards
7 cards from real CRE practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Documentation and Reporting flashcards as text
A Reliability Assessment Report for a safety-critical system must include which additional element not typically required for commercial products?
Answer: Hazard Analysis and safety integrity level (SIL) compliance evidence
Safety-critical systems require documented hazard analysis and evidence of compliance with appropriate safety integrity levels (IEC 61508 or equivalent) within reliability reports.
What is the purpose of a 'redline' or 'as-built' document in the context of reliability program documentation?
Answer: To capture all differences between the approved design and what was actually manufactured
As-built (redline) documents record deviations between the released design drawings and the actual configuration of manufactured units.
Which statistical parameter must be reported alongside a demonstrated MTBF to make the test result meaningful for decision-making?
Answer: The confidence interval (lower and upper confidence bounds)
A demonstrated MTBF without confidence bounds is statistically incomplete; confidence intervals communicate the uncertainty inherent in the finite test sample.
In a Maintainability Demonstration Report, which metric is typically documented to characterize active repair time?
Answer: Mean Active Corrective Maintenance Time (Mct)
Mean Active Corrective Maintenance Time (Mct) measures the average hands-on time to diagnose and repair a failure, and is the primary maintainability metric demonstrated and reported.
A reliability engineer is drafting a Derating Analysis Report. What must be documented for each component to demonstrate compliance?
Answer: Applied stress vs. rated stress and the resulting derating percentage for each stress parameter
Derating reports must show both the applied stress (voltage, current, temperature, etc.) and the rated maximum, along with the calculated derating percentage compared to the program's derating criteria.
Which element distinguishes a Preliminary Hazard Analysis (PHA) document from a detailed FMEA?
Answer: PHA is performed at system level early in design using qualitative hazard identification
A PHA is a high-level, qualitative hazard identification performed early in the design lifecycle before detailed design information is available, unlike a detailed quantitative FMEA.
When documenting an Accelerated Life Test (ALT) report, which information is critical for converting test results to field-use life predictions?
Answer: The acceleration model used (e.g., Arrhenius) and its empirically validated parameters
The acceleration model and its parameters (such as activation energy for Arrhenius) are essential for mathematically translating accelerated stress results back to expected field life.