Why has the number of unintentional injuries and deaths not improved in the United States for the last 15 years? Are we finding effective corrective actions or are we just counting the causes? While fluctuations occur from year to year, no significant improvement in the accident rate has been recorded since about 1981. The trend seems to indicate we are losing ground. Why this stagnation after a steady decrease in the accident rate for the previous 15 years? The Federal Aviation Administration recently noticed the same trend in the number of aircraft fatalities. Their studies concluded that the stagnation is caused by using the same old accident analysis methods. While we can not expect to solve today's problems with yesterday's thinking, what is wrong with yesterday's thinking? At General Electric Medical Systems we concluded that our investigation process was not working. We were not satisfied with our progress on accident reduction. We conducted a cursory review of accident investigation reports and found too much fault finding and not enough fact finding. We knew something needed to be done, so we decided to apply six sigma methods to review and evaluate our accident investigation process. This paper will share the results of that evaluation and provide a comparison of current accident investigation methodologies.
The six sigma process involves four key steps:
Define and Measure
Analyze
Improve
Control
In the Define and Measure Phase, the deliverables are to identify the project elements that are critical to quality (CTQ), to develop an approved problem definition (R0), to create a high level process map, to identify the project response variable (Y), to collect data, to assess the performance standards, to analyze the measurement system capability and to determine performance capability.
In the Analysis Phase, the products are to prioritize the list of all X's to identify the likely families of variability (vital few) through graphical analysis, ANOVA and basic statistical tools, and to quantify financial opportunities.
In the Improve Phase, the results are confirmed vital X's, an optimized solution, a confirmed solution and a risk assessment plan.
Finally, in the Control Phase, the expectations are a sustained process (mistake proof, tolerance the process and monitor (SPC)), project documentation and translated learnings.
At General Electric Medical Systems (GEMS) we started with fundamental quality tools and created a process map of the accident investigation process. We compared site process maps to make sure they were the same. There were a few surprises! There was tremendous inconsistency with the application of the existing investigation tool that we were using.
We developed an Ishikawa fishbone diagram to try to understand the breakdowns in our accident/ incident investigation process. We evaluated our accident investigation form. How thoroughly and accurately were the forms completed? Did the investigation documentation indicate that we got to the root causes or did we blame the employees? We looked for opportunities to make the form easier to use.
