Ishikawa Diagrams

In the 2" step we try to figure out all relevant uncertainty sources that infln-ence the parameters identified in step 1. The figure shows a fishbone or Ishikawa diagram that is helpful to get an overview. 

Figure 4.6. Generic cause-and-effect (Ishikawa) diagram.

Cause and effect diagram. This is also known as the Ishikawa diagram. This was introduced as a formal way of representing a specific effect and the possible causes that influence this effect. They are used to display all the possible causes of a specific problem and are usually constructed around two sets of four basic causes. 

Figure 20.1 Ishikawa diagram of the parameters which lead to the area of an HPLC peak. Mass means the weighed sample or analyte. For its dilution n measuring flasks (MF) and m pipettes (Pip) are needed. MPE is the maximum permissible error of a volumetric operation, i.e. the combined effects of calibration uncertainty and repeatability. Other abbreviations z = wavelength acc.= accuracy rep. = repeatability S/N = signal-to-noise ratio.

Cause-and-effect diagram Fishbone diagram Ishikawa diagram Control charts Why-why diagram Brainstorming Flowcharts... 

Cause-effect diagram (fishbone or Ishikawa diagrams)... 

This paper is focuses on the study of Ep for the above reliability target. The paper uses Ishikawa diagrams to analyse the influence of factors related to... 

Figure 4. Ishikawa diagram of the factors that influence signal at point A... 

Figure 5. Ishikawa diagram of Pp from a functional block point of view...

The paper shows that it is possible to analyse the influence of the functional performance of the OBBTE on the rehability target. Ishikawa diagrams are a useful tool to organize this kind of analysis. The results of the analysis are useful in two ways firstly, they can be used to provide a proof that the rehability target is met secondly, they help to make design decisions. 

It is essential to diseover what the root cause of a problem is and after a team effort brainstorming session, it is helpful to construct a Pareto Chart, where groups of similar data are arranged in order of magnitude (Figure 18.14). This helps to eoncentrate on major problems. The so ealled 80/20 rule suggests that 80% of the problems result from 20% of the eauses. A eause and effects analysis is determined and a Fishbone (Ishikawa) diagram... 

From a standardized template, an Ishikawa diagram (Figure 6.7) was constructed during the root cause analysis. The template was displayed during the root cause analysis as a visual aid for the participants. The exact labels for the categories were somewhat flexible and were refined overtime. Participants identified as many contributing factors as possible, and the session facilitator added them to the chart as they were identified. 

FIGURE 6.7. ISHIKAWA DIAGRAM ROOT CAUSE ANALYSIS TEMPLATE... 

There are many problem solving and improvement tools and techniques. The most common are root cause or cause and effect diagrams (also known as fish-bone or Ishikawa diagrams). Other techniques include flow charts, input-output analysis, scatter diagrams and why-why analysis. 

The three types of standards, and codes of practice, should be hsted as reference material from a consultant in the specialized area. The consultant should be up to date with the available information. These documents provide an immediate soiuce of information for the partieular hazard in question, and are available in hard copy or electronic format Another method which can be used when assessing a risk is to assess the relationship between the causes and effects of a risk. The process for doing this is represented in the Fishbone or Ishikawa diagram above (see Fig. 4.3). 

Ishikawa diagrams (Fishbone Charts)— used to create problem and solution visibility by grouping problem causes into branches. Often this is referred to as a cause-and-effect diagram. Using this tool in conjunction with the PDCA process helps to narrow down the root cause. 

A fish bone diagram is an Ishikawa diagram, which is used to analyze problems and show the various causes of an event. It is sometimes used in accident/ mishap investigations. 

Figure 2.45 shows the Ishikawa diagram concept. Notice that it tends to look like a fish bone, explaining the derivation of its alternate name. The primary and secondary causes are listed in the fishbone lines. 

Ishikawa diagrams are used to help analyze problems (or mishap) and determine the causes for the problem. It provides a methodology for including... 

Figure 2.45 Ishikawa diagram (or fish bone diagram).

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