Scatterchart and concentration diagrams

Scatterchart and concentration diagrams

Architectural diagram

Depending on what you need, a scatterchart or concentration diagram may also be useful.


Problems can impact on one another. A scatterchart can show the relationships between two causes or other variables, it does not by itself prove that one variable causes the other.
NB. Each cause must be able to be expressed as a numerical value.

Typical use:

  • Exploring the chain of causes by understanding the impact one cause at one level has on the cause(s) at the next level
  • Ruling out causes at different levels that are not linked to the root cause

Concentration diagram

Where data are linked to a location, a concentration diagram can help to connect registered problems to physical locations.

A concentration diagram may reveal patterns of occurrence, especially where problems occur in physical systems or facilities. This can highlight which location to focus efforts on.

Typical use:

  • To identify patterns in problem occurrences
  • Can be used for products, processes or plant locations
  • Ideal for looking at proliferation and locations of pest activity within a building (below)

Concentration diagram of tea shop

Pests such as insects, rodents etc. present a food safety hazard. It may be useful in a root cause analysis investigation to increase awareness about the relationship between the number of insects trapped in a specific time period and their proximity to an infestation source.

When this information is presented graphically, such as in this type of concentration diagram - known as a contour map - it is clear to track heightened activity of insects and their movements. It helps to identify the centres that require treatment which may help to identify the root cause.

This diagram can also be useful to communicate the effectiveness of control measures to maintenance, sanitation and pest control personnel.