Know your data

Often we gather data to aid in solving a problem we encounter. One trap that you can fall into is that the data is not exactly what you think it is. For example, you might be taking pressure readings from a process line to decide whether a filter is plugged. The pressure readings may be normal leading you to believe that the filter is not plugged and in satisfactory condition. However, if the pressure gauge is upstream of the filter, then the data is misleading you. The filter may be plugged but the pressure gauge location is misleading you.

This is particularly a problem if you don't have good change control on your equipment. The diagram you are working on may not reflect reality. It is always a good idea to go look at what you're working on, both the help you visualize the process and to make sure things are as you think they are. The biggest danger to problem solving is thinking you can sit back in your office and just think through the problem.