The check sheet is an incredibly powerful and versatile tool that sees a lot of use in lean organizations. It can be easily adapted to a number of different contexts, and mastering its use can lead to great results in terms of increase in your productivity and the accuracy of each operation performed by the company. To accommodate the different popular use cases for the tool, four general common check sheet types have been created over time. It’s important to understand the specific intended use of each one, so that you’ll know how to pick the most appropriate tool for any given situation.
1. Process probability distribution check sheet
A check sheet can be very useful for getting some preliminary frequency distribution data while you’re measuring a process and collecting information about its performance. The main point of the sheet is to give you a visual representation of the probabilistic distribution of certain factors in the execution of the process, something which can become very clear and noticeable with a quick glance at a process probability distribution sheet. An important point when working with this type of sheet is to set the appropriate upper and lower limits according to the specification. This will allow you to immediately identify outliers in the data and figure out if a specific area needs extra adjustment.
2. Defect type sheet
When dealing with defects in your processes, it’s a good idea to be able to categorize them according to factors like defect type and occurrence frequency. The defect type sheet is a simple type of check sheet used to mark the occurrence of a specific defect, allowing you to easily count them later on. That way, you can just plug the data into a statistical analysis tool and you’ll get an easy overview of the current state of defects in your project. If a particular problem is coming up more often than others with a noticeably greater frequency, this is a great tool to point that out.
3. Defect location sheet
Similar to the above, but focused specifically on tracking the location where different defects occur. This can be an extremely powerful tool when combined with the defect type sheet, and it’s not uncommon to see both used alongside each other in organizations during phases of seeking out and eliminating causes of defects. When it comes to simple, but powerful statistical tools that can help you get the full picture of your current situation, combining a defect location sheet with a defect type sheet can give you a lot of useful information with relatively little effort. Of course, it’s up to you to actually apply proper statistical analysis methods to make something useful with that data, but at least you have access to the raw data in the first place.
4. Defect cause sheet
The defect cause sheet tracks exactly what its name implies what caused each defect in your process, using the same format as the Defect type sheet above. This is not always critical information, depending on what exactly you’re looking for, but if you’re running root cause analysis or something along those lines, the information collected from a defect cause sheet can be handy down the road. Just make sure that you have an adequate process in place for tracking the actual cause of each issue, because the fundamental design of the defect cause sheet doesn’t give you any capability to detect and correct errors.