CRE (ASQ) study guide
CRE · Work through your exam, one topic at a time.
The Certified Reliability Engineer (CRE) is a professional certification offered by ASQ for practitioners who specialize in improving the reliability, maintainability, and safety of products, systems, and processes. According to ASQ, a CRE focuses on identifying potential failures, optimizing performance, and ensuring compliance with quality and reliability standards. The CRE study guide has 7 sections and about 2,033 words.
01Reliability Engineering Fundamentals
Reliability is the probability that an item performs its required function under stated conditions for a stated period. Every word matters: probability (so it is a random variable, expressed 0-1 or as a percentage), required function (defined by a specification), stated conditions (stress, environment, duty cycle), and stated period (time, cycles, miles).
358 words, about 2 min02Reliability Management and Leadership
A reliability program is a planned set of tasks sized to the product's criticality, cost of failure, and customer expectations. Candidates should recognize the elements: reliability requirements allocation, design reviews, failure reporting and corrective action (FRACAS), supplier control, test planning, and growth management.
287 words, about 1 min03Design and Development for Reliability
DFR builds reliability in rather than testing it in. Key tools: derating (operating parts below rated stress), robust design (Taguchi methods, parameter and tolerance design), design of experiments, and redundancy.
290 words, about 1 min04Reliability Modeling and Prediction
A reliability block diagram (RBD) represents the logic of success, not necessarily the physical layout. Series blocks are all required; parallel blocks provide redundancy.
297 words, about 1 min05Reliability Testing and Data Analysis
Know the purpose of each: reliability demonstration (verify a requirement), reliability growth (improve), accelerated life testing (compress time via stress), environmental testing (expose to conditions), and screening/burn-in (remove early failures). Traps: using a demonstration test to claim growth, or an accelerated test without validating the acceleration model.
241 words, about 1 min06Maintainability, Maintenance, and Availability
Maintainability is the probability that a failed item can be restored within a stated time using stated resources. It is measured by mean time to repair (MTTR), repair rate mu = 1/MTTR, and the maintenance time distribution (often lognormal).
281 words, about 1 min07Safety, Risk, and Failure Analysis
Risk combines severity and likelihood. Know the hierarchy: identify hazards, assess risk, reduce risk, and verify.
279 words, about 1 min