Environmental Engineering Reference
In-Depth Information
Reselect metrics
if needed
Act
Plan
Select metrics
Reassess impacts
Develop new
improvement strategies
Incorporate learning in
wider changes
Assess impacts
Identify processes
Develop improvement
strategy
Apply metrics
Analyze results
Conduct improvement on
a small scale
Identify what
you have
Check
Do
Figure 5.7
Efficiency improvements in a four-step approach using the Plan-Do-Check-Act cycle.
problem identification and goals setup. In the Do phase, improvement strategies are created
and tried on a small scale. The Check phase consist of measuring and identifying the results
of the changes that were introduced as well as the main learning attained in the process.
During the Act phase, the positive results are incorporated to the particular problem in analysis
and to similar processes. If results were not positive, a new strategy is needed.
Other tools with application in efficiency improvement
In addition to flowcharts, Pareto diagrams, and PDCA cycles, a variety of other quality
tools can be used for problem identification and solving. For problem identification, a
set of seven quality tools are available, including cause-and-effect diagrams, histograms,
control charts, Pareto diagrams, check sheets, scatter plots, and stratification (Rooney
et al., 2009). A brief explanation of each tool is described in this section however, read-
ers with interest in more details may consult subject-specific literature (e.g., Tague,
2004).
Cause-and-effect diagrams, also called fishbone diagrams, link different causes to a
particular problem in a graphic approach. Causes typically are associated with factors,
such as people, methods, materials, machines, management, and work environment. A
cause-and-effect diagram is built by writing the problem in a box on the right-hand side
of a sheet of paper followed by a line drawn horizontally from the box to the left. Then
the main factors are added at the end of oblique lines that intersect with the horizontal
line. Next each factor is analyzed and the causes for each factor are brainstormed and
incorporated into the diagram. Figure 5.8 presents a bonefish diagram that identify
