ASQ’s CRE Body of Knowledge

Taken in entirety from https://p.widencdn.net/evlmel/certified-reliability-engineer on August 6th, 2018. This is the 2018 update to the CRE BoK.

Reprinted with permission from American Society for Quality ©2018 ASQ, www.asq.org. No further distribution allowed without permission.

Body of Knowledge

Certified Reliability Engineer (CRE)

Topics in this Body of Knowledge include additional detail in the form of subtext explanations and the cognitive level at which the questions will be written. This information will provide useful guidance for both the Examination Development Committee and the candidates preparing to take the exam. The subtext is not intended to limit the subject matter or be all-inclusive of what might be covered in an exam. It is intended to clarify the type of content to be included in the exam. The descriptor in parentheses at the end of each entry refers to the highest cognitive level at which the topic will be tested. A more comprehensive description of cognitive levels is provided at the end of this document.

I. Reliability Fundamentals (25 Questions)

I. A. Leadership Foundations

1. Benefits of reliability engineering
   Describe the value that reliability has on achieving company goals and objectives, and how reliability engineering techniques and methods improve programs, processes, products, systems, and services.  (Understand)
2. Interrelationship of safety, quality, and reliability
   Describe the relationship of and distinguish between reliability and quality, and describe the importance of safety in reliability engineering and how reliability impacts safety. (Understand))
3. Reliability engineer leadership responsibilities
   Describe how to be a reliability champion by influencing program decisions and facilitating cross-functional communication. (Understand)
4. Reliability engineer role and responsibilities in the product life cycle
   Describe how the reliability engineer influences the product life cycle, and describe a reliability engineer’s role in the design review process in order to anticipate how reliability can impact risk and costs, and ensure performance over time. (Understand)
5. Function of reliability in engineering
   Describe how reliability techniques can be used to apply best practices in engineering (e.g., measuring reliability early), how industry standards can impact reliability, and how reliability can inform the decision analysis process. (Analyze)
6. Ethics in reliability engineering
   Identify appropriate ethical behaviors for a reliability engineer in various situations. (Evaluate)

I. B. Reliability Foundations

1. Basic reliability terminology
   Explain basic terms related to reliability and the associated metrics (e.g., MTTF, MTBF, MTTR, service interval, maintainability, availability, failure rate, reliability, and bathtub curve). (Apply)
2. Drivers of reliability requirements and targets
   Describe how customer expectations and industry standards, safety, liability, and regulatory concerns drive reliability requirements. (Understand)
3. Corrective and preventive action (CAPA)
   Identify corrective and preventive actions to take in specific situations and evaluate their measures of effectiveness. (Evaluate)
4. Root cause analysis
   Describe root cause analysis, and use a root cause and failure analysis tool to determine the causes of degradation or failure. (Evaluate)
5. Product life-cycle engineering stages
   Describe the impact various life-cycle stages (concept/design, development/test, introduction, growth, maturity, decline) have on reliability, and the cost issues (product maintenance, life expectation, software defect phase containment, etc.) associated with those stages. (Understand)
6. Economics of product maintainability and availability
   Describe the cost tradeoffs associated with product maintainability strategies and availability. (Understand)
7. Cost of poor reliability
   Describe how poor reliability affects costs over the life cycle. (Understand)
8. Quality triangle
   Describe the relationship between cost, time, and quality with respect to reliability. (Understand)
9. Six Sigma methodologies
   Describe how Six Sigma principles support reliability engineering. (Understand)
10. Systems engineering and integration
    Describe the role of reliability engineering within systems engineering, including the integration of components and their interfaces/interactions within the system. (Understand)

II. Risk Management (25 questions)

II. A. Identification

1. Risk management techniques
   Use risk management tools and processes to identify, document, and track concerns. Identify and prioritize safety, economic, performance, and customer satisfaction concerns utilizing an appropriate risk management framework. (Analyze)
2. Types of risk
   Identify the various types of risks, including technical, scheduling, safety, and financial, and describe their relationship to reliability. (Analyze)

II. B. Analysis

1. Fault tree analysis (FTA)
   Use fault tree analysis (FTA) techniques to evaluate product or process failure. (Analyze)
2. Failure mode and effects analysis (FMEA)
   Define and distinguish between failure mode and effects analysis (FMEA) and failure mode, effects, and criticality analysis (FMECA) and apply these techniques to systems, products, processes, and designs. (Evaluate)
3. Common mode failure analysis
   Describe common mode failure (also known as common cause failure) and how it affects risk. (Understand)
4. Hazard analysis
   Describe how hazard analysis informs the development process, and how information obtained as a result of the hazard analysis is used by the reliability engineer. (Understand)
5. Risk matrix
   Describe how risk matrices are used in the assessment of risk in regard to likelihood and severity. (Understand)
6. System safety
   Identify safety-related issues by analyzing customer feedback, design data, field data, and other information. Prioritize safety concerns, and identify steps that will minimize the improper use of equipment, products, or processes. (Evaluate)

II. C. Mitigation

Identify appropriate risk mitigation (treatment) plans to include controls that will minimize risk and subsequent impact in terms of safety, liability, and regulatory compliance. (Evaluate)

III. Probability and Statistics for Reliability (35 questions)

III. A. Basic Concepts

1. Basic statistics
   Define various basic statistical terms (e.g., population, parameter, statistic, sample, the central limit theorem, parametric, and nonparametric), and compute and interpret their values. (Analyze)
2. Basic probability concepts
   Use basic probability concepts (e.g., independence, mutually exclusive, conditional probability), and compute and interpret the expected values. (Analyze)
3. Probability distributions
   Compare and contrast various distributions (e.g., binomial, Poisson, exponential, Weibull, normal, and log-normal), and recognize their associated probability plots. (Analyze)
4. Probability functions
   Compare and contrast various probability functions (e.g., cumulative distribution functions (CDFs), probability density functions (PDFs), and hazard functions), and recognize their application in various situations. (Apply)
5. Sampling plans for statistics and reliability testing
   Use various theories, tables, and formulas to determine appropriate sample sizes or testing time for statistical and reliability testing. (Apply)
6. Statistical process control (SPC) and process capability studies (Cp, Cpk)
   Define and describe SPC and process capability studies (Cp, Cpk, etc.), control charts, and how each is related to reliability. (Understand)
7. Confidence and tolerance intervals
   Compute confidence intervals and tolerance intervals, draw conclusions from the results, and describe how point estimates are used to determine the interval. (Evaluate)

III. B. Data Management

1. Sources and uses of reliability data
   Describe sources of reliability data (prototype, development, test, field, warranty, published, etc.), their advantages and limitations, and how the data can be used to measure and enhance product reliability. (Analyze)
2. Types of data
   Identify and distinguish between various types of data (e.g., attributes vs. variable, discrete vs. continuous, censored vs. complete, and univariate vs. multivariate). Select appropriate analysis tools based on the data type. (Evaluate)
3. Data collection methods
   Identify and select appropriate data collection methods (e.g., surveys, automated tests, automated monitoring, and reporting tools) in order to meet various data analysis objectives and data quality needs. (Evaluate)
4. Data summary and reporting
   Examine collected data for accuracy and usefulness. Analyze, interpret, and summarize data for presentation using various techniques, based on data types, sources, and required output. (Create)
5. Failure analysis methods
   Describe failure analysis tools and methods (e.g., mechanical, materials, physical analysis, and scanning electron microscopy (SEM)) that are used to identify failure mechanisms. (Understand)
6. Failure reporting, analysis, and corrective action system (FRACAS)
   Identify elements necessary for FRACAS, and demonstrate the importance of a closed-loop process. (Evaluate)

IV. Reliability Planning, Testing, and Modeling (35 questions)

IV. A. Planning

1. Reliability test strategies
   Develop and apply the appropriate test strategies (e.g., truncation, test-to-failure, degradation, growth plan, and test, analyze, and fix (TAAF)) for various product development phases. (Evaluate)
2. Environmental and conditions of use factors
   Identify environmental and use factors (e.g., temperature, humidity, and vibration) and stresses (e.g., severity of service, electrostatic discharge (ESD), throughput, and duty cycle) to which a product may be subjected. (Analyze)
3. Failure consequence
   Describe the importance of identifying the consequences of failure modes when establishing reliability acceptance criteria. (Understand)
4. Failure criteria
   Define and describe failure criteria based on system requirements and warranty terms and conditions. (Understand)
5. Test environment
   Appraise the environment in terms of system location and operational conditions, and designate the environment in the test plan to ensure an appropriate test strategy is implemented. (Evaluate)

IV. B. Testing

Describe the purpose, advantages, and limitations of each of the following types of tests, and use common models to develop test plans, evaluate risks, and interpret test results. (Evaluate)

1. Accelerated life tests
   (single-stress, multiple-stress, sequential stress, step-stress, HALT, margin tests)
2. Stress screening
   (ESS, HASS, burn-in tests)
3. Qualification/ Demonstration testing
   (sequential tests, fixed-length tests)
4. Degradation
   (wear-to-failure) testing
5. Software testing
   (white-box, black-box, operational profile, and fault-injection)

IV. C. Modeling

1. Reliability block diagrams and models
   Generate and analyze various types of block diagrams and models, including series, parallel, partial redundancy, and time-dependent. (Evaluate)
2. Physics of failure and failure mechanisms
   Identify various potential failure mechanisms (e.g., fracture, corrosion, memory corruption) and describe the physical process of these failures. (Apply)
3. Failure models
   Select appropriate theoretical models (e.g., Arrhenius, S-N curve) to assess or predict failure rates. (Analyze)
4. Reliability prediction methods
   Use various reliability prediction methods (e.g., Monte Carlo Simulation, part stress analysis, and parts count prediction) for both repairable and nonrepairable components and systems, and describe the inputs into the model. (Apply)
5. Design prototyping
   Describe the advantages and limitations of prototyping to enhance product reliability. (Understand)

V. Life-Cycle Reliability (30 questions)

V. A. Reliability Design Techniques

1. Design evaluation techniques (validation and verification)
   Explain how validation, verification, and other review techniques are used to assess the reliability of a product’s design at various life-cycle stages. (Apply)
2. Stress-strength analysis
   Apply the stress-strength analysis method of calculating probability of failure, and interpret the results. (Analyze)
3. Design of experiments (DOE)
   Develop and interpret the results of a standard design of experiments (DOE) (e.g., full factorial and fractional factorial). (Analyze)
4. Reliability optimization
   Use various approaches to optimize reliability within the constraints of cost, schedule, weight, and other design requirements. (Apply)
5. Human factors
   Describe the relationship between human factors and reliability engineering, including user safety, user and usage profiles, failure modes, and mechanisms. (Understand)
6. Designs for X (DFX)
   Apply DFX techniques such as design for manufacturability, testability, and maintainability. (Apply)
7. Designs for Reliability (DfR)
   Apply DfR in order to meet reliability requirements throughout the product or system life cycle. Understand how built-in reliability and fault tolerance/avoidance are key goals for design for reliability. (Evaluate)

V. B. Parts and Systems Development

1. Materials and components selection techniques
   Apply techniques (e.g., derating and commercial off-the-shelf (COTS)) for selecting materials and components to meet reliability goals and requirements. (Analyze)
2. Parts standardization and system simplification
   Describe the importance of standardization, simplification, and parts re-use to meet reliability goals and requirements. (Apply)

V. C. Maintainability

1. Maintenance strategies
   Develop a maintenance plan incorporating various strategies (e.g., predictive maintenance, repair or replace decision making, spare parts analysis/forecasting, and equipment warranties). (Apply)
2. Preventive maintenance (PM) analysis
   Define and use PM tasks, optimum PM intervals, and other elements of this analysis. Identify situations when PM is not effective. (Apply)
3. Corrective maintenance analysis
   Describe and apply the elements of corrective maintenance analysis (e.g., fault-isolation time, repair/replace time, skill level, and crew hours). (Apply)

In addition to content specifics, the subtext for each topic in this BOK also indicates the intended complexity level of the test questions for that topic. These levels are based on “Levels of Cognition” (from Bloom’s Taxonomy – Revised, 2001) and are presented below in rank order, from least complex to most complex.

Remember
Recall or recognize terms, definitions, facts, ideas, materials, patterns, sequences, methods, principles, etc.

Understand 
Read and understand descriptions, communications, reports, tables, diagrams, directions, regulations, etc.

Apply 
Know when and how to use ideas, procedures, methods, formulas, principles, theories, etc.

Analyze
Break down information into its constituent parts and recognize their relationship to one another and how they are organized; identify sublevel factors or salient data from a complex scenario.

Evaluate
Make judgments about the value of proposed ideas, solutions, etc., by comparing the proposal to specific criteria or standards.

Create 
Put parts or elements together in such a way as to reveal a pattern or structure not clearly there before; identify which data or information from a complex set is appropriate to examine further or from which supported conclusions can be drawn.