Improving Processes & Services

Process Tools

Data Handling

Concentration Diagrams

In an electronics assembly factory, the inspector at the end of a production line of printed circuit board assemblies would have a picture or drawing of the printed circuit board showing all the various components etc. When they found a fault, they would simply mark the faulty component on the drawing, creating over a week a simple analysis of where the faults were occurring.

The Police do the same to identify accident "black-spots". Televised cricket does something similar with bowler accuracy.

These are all concentration diagrams. Their great advantage is that the data becomes easy to collect and then needs little or no analysis - the diagrams are almost self analysing. It is used to identify accident black-spots in offices (see below) and can also be used to identify which boxes on a form get filled in incorrectly.

Accidents in an Office

example concentration diagram


The general procedure is:

Step 1 - Define the fault or faults (or whatever) being investigated.

Step 2 - Make a map, drawing, or picture.

Step 3 - Mark on the diagram each time a fault (or whatever) occurs and where it occurs.

Step 4 - After a sufficient period of time analyse it to identify where the faults occur. Perhaps simply when a pattern starts to develop,


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