100-Metodos-de-Qualidade-Total

166 100 METHODS FOR TOTAL QUALITY MANAGEMENT
Method 73
Concentration diagrams
Purpose
To collect data when the location of a defect or problem is important.
When to use
Either during problem definition when you are coIIecting data to find out
what is happening, or when you have implemented a solution and you are
coIIecting data to monitor the new situation.
How to use
There are five simple steps to draw a concentration diagram:
1 Agree the data to be coIIected. This step is vital: you cannot analyse
data that have not been collected.
2 Design the concentration diagram .
3 Test the diagram using someone who has not been involved in the
design. Get him or her to use the diagram without assistance. If
necessary, modify the diagram.
4 Design a master concentration diagram. If more than one person is to
be involved in data collection, you will need to bring together all the
data collected. The way to do this is to use a master diagram.
5 Collect the data.
Benefits
By establishing the facts about the location of failure, a team can plan to
identify the causes of failure and look for ways of removing them. Actions
are taken on the basis of evidence, not feeling.
Concentration diagrams are an excellent way of involving people in
administration areas in quality improvement. They provide a simple
method of data collection that can be easily understood and applied in
office areas.
Example
A large organization was concerned about the number of road accidents
happening on the site, covering approximately 10 miles by 3 miles.