Failure modes and effects analysis

If ever there were a topic that sounded more appropriate for plant maintenance and engineering, I don't know what it could be. Maintaining the highest degree of productive uptime is what you do for a living. It's one secret to the success of any manufacturing operation. And it's the plant manager and the engineering staff who sniff out the root causes of equipment failure and prioritize the time devoted to a problem on the basis of the failure's consequence. Expertise with failure modes and effects analysis is something that ought to be of value to any plant professional.

Join me for this month's dive into the morass we call the Web in search of zero-cost, non-commercial, registration-free resources aimed at providing you with practical information to head mechanical failures off at the pass. Remember, we search the Web so you don't have to.

The United States military first developed and published a methodology for failure mode and effects analysis right after World War II. Originally designed to ensure a degree of reliability that would protect the safety of troops and equipment, the document has since been adopted and adapted by a number of organizations for a variety of purposes. A brief history of the original document resides at http://www.fmeca.com/ffmethod/history.htm, courtesy of The Haviland Consulting Group in Grand Rapids, Mich.

Many of the FMEA variants emerged in the form of applications customized for product design purposes. It is, after all, more sensible to design safety and reliability into a product before the marketplace makes it abundantly clear that it's only so much unusable junk rolling off someone's assembly lines. Other variants focus on the healthcare field, a venue where reliability and safety are, in the main, good things to have happen.

An efficient way to access information about a particular topic is through a Web site that links to other related Web resources. One such Web site is The FMEA Info Centre, operating from Oostmalle, Belgium. It bills itself as a non-commercial, Web-based inventory dedicated to the promotion of our topic for the month.

The features your mouse can uncover there include the latest scoop on books and publications about the FMEA, abstracts of technical papers published between 1996 and 1999, links to consultants, downloads, example calculations, as well as links to FMEA research, software and standards. The site is an international entity and some material is presented in German, French and other languages. Let your mouse sneak its way into this portal at http://www.fmeainfocentre.com/ to get a good grounding in the world of FMEA.

Incidentally, there are two download areas on this site. One is accessed from the main menu at the top of the home page. The second is more difficult to find, probably because of the typo in the URL http://www.fmeainfocentre.com/downlaod_area.htm.

FMEA requires one to identify and describe each specific risk to be analyzed and attach numerical values to three relevant variables. This forms a matrix, a worksheet, which documents your calculations and subsequent analysis.

To get started, you'll need a blank FMEA worksheet. A good place to get one is from Adams 12, Five Star Schools in Thornton, Colo. Download the PDF, sharpen your pencil, give it some thought and you're in business. Have your mouse fetch the sheet from http://www.adams12.org/Quality/documents/FMEAWorksheet.pdf.

The typical FMEA program assigns a value to three variables (severity, probability, detectability) needed for a straightforward computation that determines the relative importance of a particular failure mode. It's a good idea for your FMEA program to include a standard so that everyone examining a particular failure mode can establish reasonably similar estimates for the three factors. An example of one such standard is found on the Web site operated by iSixSigma LLC, Ridgefield, Conn. Have your mouse climb up to http://www.isixsigma.com/tt/fmea/ to click on FMEA For Information Technology. Although the rating standard shown there is for IT purposes, the generic aspects of the approach that are useful for plant maintenance and engineering will jump off the screen into your lap.

OK, so we know how to agree on the numbers, right? Now what? That's a question someone posted to the iSixSigma forum. As you would expect, there are experts out there with answers. Before you leave this site, take the time to read the advice offered to one FMEA beginner. The specific forum page is http://main.isixsigma.com/forum/showmessage.asp?messageID=30127. Don't bother with the follow-up entries listed at the bottom. They add nothing new to the discussion.

The next step is to start filling out the paperwork. There's a good example of a completed worksheet on the Web, posted there by our friends in Belgium. This Excel spreadsheet, found at www.fmeainfocentre.com/download/fmeaIII.xls, is a self-contained FMEA program in progress. It includes a functional FMEA worksheet, an explanation of cell contents and color-coded standards for assigning values to the variables.

By way of comparison, investigate the FMEA worksheet format that Safety Management Services Inc., West Jordan, Utah, uses for process hazards analysis. Mouse your way to http://www.smsink.com/services_pha_fmea.htm. Read the explanatory main body copy, then move to the upper right and click on the links to the completed sheets.