The workshop team analyses the data as has been explained in the previous chapter.
This time of analysis will probably be one of the few times when the team gathers in a meeting room; the meeting room should not be too far away from the area, and at Fig. 5.6 Activity analysis worksheet
best would obviously have a direct view of the area. The walls are then plastered with value stream maps, information, data, photos, and so on (see Fig.5.9), and the team leader collects all other documents that could be useful when analyzing waste.
At this stage of the meeting, other data can be collected by viewing step-by-step videos of the operations: usually information regarding times and how the activities work. The team then enters the delicate stage that involves finding causes of waste.
The methods of brainstorming most often used come from traditional quality management and include:
• Cause-effect and fishbone diagrams;
• 5 WHYs;
• 8D problem solving.
Occasionally, a team may have to use statistical methods to check, for example, the correlation between factors and results, or to understand the distribution and frequency of data. In these cases, methods that concentrate more on the mathemati-cal and statistimathemati-cal aspects may be used:
• Correlation diagrams;
• Frequency histograms;
• Design o experiment (DOE);
• And so on.
Fig. 5.7 “Spaghetti” chart
74 5 Kaizen Workshops and How to Run Them
It should be mentioned, however, that these “advanced” methods require basic training and they also often require implementation, which could increase work-shop length.
The main goal of a Kaizen workshop is to reduce waste as quickly as possible, usually also involving the workers of the area. For this reason, “advanced” methods are usually only applied in Six Sigma projects, where the main goal is to stabilize and reduce variability of process and product/service traits.
In the data analysis stage, the team may also use flowcharts to list the possible causes of waste next to the possible solutions. Cause-effect diagrams and 5 WHYs are the methods used the most when analyzing waste causes; these can be quickly consulted if they are drawn on large sheets of paper taped to the meeting room or workshop area walls.
The steps used by 5WHYs are usually:
• Announcing the waste to the team, being as precise as possible when describing the problem.
Fig. 5.8 Photos taken before and after a 5S Kaizen event
• The team ponders the cause of waste for this first time, and then writes the explanation under the problem description.
• If the explanation does not immediately identify the cause of waste, then step two is repeated.
• Step 3 is repeated as often as necessary, until the real cause of waste is unearthed.
The 5 WHYs method is usually used together with a cause-effect or fishbone diagram, both methods used a lot in TQM and Six Sigma.
Example of a 5 WHYs Application. In an airport the waiting time for security checks was increasing on a monthly basis, even though the amount of passengers remained fairly constant. A Kaizen team decided to launch a workshop with the specific target of reducing these times. For one whole day times were recorded and the activities were filmed and photographed. When viewing this material, the team realized that the member of staff who checked the luggage on screen took a lot of time identifying objects within the bags, sometimes even having to recheck them.
By combining the cause-effect diagram with the 5 WHYs method, the team identified the cause of the problem in three steps.
Fig. 5.9 VSM drawn up during a Kaizen workshop using sticky notes and sheets of paper
76 5 Kaizen Workshops and How to Run Them
Explaining the problem
– The member of staff needs a lot of time (up to 4 min) to identify the objects in the bags
1. Why?
– The monitor brightness isn’t great, it could be either the monitor itself or the surroundings. . .Team discussion: the monitors are among the best on the mar-ket, but the brightness isn’t very good; maybe something else reduces it 2. Why?
– The monitor’s brightness is reduced by the monitor behind it. . .Team discussion:
the monitors behind are information boards for passengers and they don’t seem to be that bright; but they are also used to display ads
3. Why?
– Ads are much brighter than the information for passengers
Once the causes of waste have been identified, the team proceeds to remove them. Kaizen workshops are simple and quick events, thus removing projects should be planned and carried out swiftly. Action implementation usually only takes a few hours (moving a workplace, printing signs, and so on) and thus documentation should also be pretty “lean”. The checklist in Fig.5.10, for example, is a simple registration used both in the analysis and in the improvement action implementation stage.
The team should assign to each activity a level of waste after having analyzed the data collected at the beginning:
1¼ low waste;
2¼ limited waste;
3¼ relevant waste;
4¼ very high waste.
Waste level 1 does not mean zero waste according to the improvement principle that there is always room for improvement.
The improvement gained is then, once again, measured on a scale of one to four:
1¼ no improvement;
2¼ limited improvement;
3¼ significant improvement, however not reaching the target;
4¼ improvement right on target.
The last column briefly sums up the actions the team must take to remove the causes. The points assigned for improvement help to check the efficiency of the whole workshop thus leading to the final inspection, result presentation and cele-bration stage.