Failure modes and effects analysis refers has been defined as a "methodology for analyzing potential reliability problems early in the development cycle" (Crow, 2002). FMEA can be outlined on a spreadsheet. The objective of the FMEA methodology is that the company can understand the potential problems that can occur early in the production cycle, and take steps to ensure that the problems are avoided or mitigated (Ibid). The process for conducting a FMEA analysis has two parts: analyzing the current process and tracking improvement over time (IHI, 2011).
For Java Coffee, ten potential failure modes were identified in the coffee production process. iSixSigma argues that the first failure mode for a coffee shop is "clean coffee pot," so that is a good second step after purchasing the ingredients. That site points out that an important part of the FMEA process is to evaluate how severe each problem is, as that will help the managers prioritize their fixes and the strength of their controls (Williams, 2010).
The FMEA chart for Java Coffee's coffee production process is noted in Appendix A. According to the chart, the greatest risks are at the end of the process. FMEA is most particularly concerned with process risk management so it is the processes with the highest risk that need to be addressed first and foremost (Carbone & Tippett, 2004). According to this analysis, the greatest risk to serving a great cup of coffee is in the service function. The reason this is such a great risk is because of the risk of bad service -- the frequency with which this occurs is relatively high, and the impact on the customer is strong. Detection is almost always going to occur because the manager or other staff will notice the bad service or the unhappy customer.
The mode with the second-greatest RPN score is "add water." This risk is high because it is frequent, is hard to detect and has an impact on the quality of the cup of coffee, which will either be too strong or too weak. The impact on the flavor of the coffee will be noticeable, but not to the point where a complaint may be registered. The shop also relies on the customers to inform about bad cups, as visual inspection is unreliable. In general, a bad cup of coffee will not receive a complaint the way that poor service will; the customer may simply assume that the joe at Java Coffee is lousy. This is why adding water is a critical task.
Two other modes have high RPN scores as well -- brewing the coffee and post service adjuncts. The former is important for the same reason as the water issue -- if the coffee is not tasting as it should it is often the customer that notices. In this case, the smell helps the staff to identify if the coffee has been burned, and this extra layer of detection makes this mode a lower RPN mode. The post service adjuncts are an issue mainly because they occur often. The issue itself is not serious, but stockouts on sugar, cream, milk, honey and other adjuncts occur several times per day, despite the best efforts of the staff.
There are three modes that have moderate RPN scores: grinding, setting up the machine and measuring the grinds. In each case, either the frequency or the severity is moderated, minimizing the impact of the error. It is important, however, that the shop eliminate errors that result in bad cups of coffee being sold to customers, as such errors increase the risk of losing the customer.
The final set of modes are those with low RPN scores: purchasing, washing the pot, and installing the filter. Purchasing is an important mode because it has the highest severity rating. If the right ingredients are not purchased/delivered, the company will be unable to serve the customers, or will have to ad-lib products. The only reason this error scores so low is that the Java Coffee has good suppliers and there has only been one such occurrence of this error in the history of the shop. The other low RPN scores are also for modes with a very low frequency score -- the error itself might be severe but it seldom happens.