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CRE Preparation Notes

Prep notes for ASQ Certified Reliability Engineer exam ISSN 2165-8633


The idea of the CRE Preparation Notes series is to provide you short practical tutorials on all the elements that make up the ASQ CRE body of knowledge. The articles provide introductionary material, basics, how-to’s, examples, and practical use guidance for the full range of reliability engineering concepts, terms, tools, and practices.


Keep your knowledge fresh with regular review of topics and tools that make up reliability engineering.


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You will find the most recent tutorials in reverse chronological order below. Below each article is the section and specific clause of the CRE Body of Knowledge that tutorial addresses. Click on those tags to find other articles on the same topic. To the right on the sidebar, there is a listing of the 7 major categories in the body of knowledge - it's a quick way to find groups of articles on each specific area. You can also use the search function to locate articles, podcasts, or tutorials on specific topics.

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10 Steps of FMEA

10 Steps of FMEA

In Chapter 8 of The Basics of FMEA by Robin E. McDermott, et. al. discusses the ten steps for an FMEA. I find it to be an excellent summary for describing and conducting a failure mode and effect analysis.

Therefore based on the work of McDermott and others, plus my own experience here are the ten steps with my descriptions. [Read more…]

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How to Read a Standard Normal Table

How to Read a Standard Normal Table

One of the most basic skills needed for the CRE exam is the ability to correctly read the Standard Normal Table.

Writing this short how-to article would be really easy if there were only one way to create the table. There isn’t. It seems every author has to create a unique way to tabulate the values. [Read more…]

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Role of Reliability in an Organization

Role of Reliability in an Organization

An effective product reliability process requires a strong team, at every level.

The team of employees within an organization that participate and impact product reliability is a vast and widespread group of people. They include members of the design team, design managers, quality and reliability engineers and managers, procurement engineers and managers, warranty managers, failure analysis specialists, members of the marketing and sales staff, members of the finance and manufacturing teams, and field service and call center staffs. [Read more…]

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2013 in Review

Thanks to you all for a great year. The idea of the blog is to assist those preparing for the CRE exam or wanting to learn about reliability engineering. It seems to have found the audience.

The WordPress.com stats helper monkeys prepared a 2013 annual report for this blog.

Here’s an excerpt:

The concert hall at the Sydney Opera House holds 2,700 people. This blog was viewed about 21,000 times in 2013. If it were a concert at Sydney Opera House, it would take about 8 sold-out performances for that many people to see it.

Click here to see the complete report.

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8 Steps to Creating an X-bar and s Control Chart

8 Steps to Creating an X-bar and s Control Chart

Once you decide to monitor a process and after you determine using an $- \bar{X} -$ & s chart is appropriate, you have to construct the charts.

The $- \bar{X} -$ & R charts use the range as an approximation of the variation in the population. When feasible use the standard deviation, s, rather than the range, R for the improved efficiency in detecting meaningful changes in process variation. [Read more…]

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8 steps to Creating an X-bar and R Control Chart

8 steps to Creating an X-bar and R Control Chart

Once you decide to monitor a process and after you determine using an $- \bar{X} -$ & R chart is appropriate, you have to construct the charts.

This is not difficult and by following the 8 steps below you will have a robust way to monitor the stability of your process. [Read more…]

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Intro to Fault Tree Analysis

Intro to Fault Tree Analysis

The NASA Fault Tree Handbook with Aerospace Applications

This is a break from the usual format of this site. I’m highly recommending that as your review materials and prepare for the CRE exam or prepare to conduct an FTA, you read this NASA document as an intro to fault tree analysis.

For a review, I suggest the first chapter or two. If working in the aerospace industry, you should print and use a copy.

The following is an extended excerpt from the first section of the document. [Read more…]

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Statistical Process Control Overview

Statistical Process Control Overview

Basic introduction to key concepts of SPC

Statistical process control (SPC) is not a control chart alone.

SPC is a set of tools and a thought process to identify, measure, monitor and improve important elements of product development and production. I’ve seen very good and very bad implementations of SPC. [Read more…]