tasks, such as lubrication, adjustments, and other preventive tasks. Determine if these procedures are being performed in a timely manner and if proper techniques are being used.
Misapplication
Misapplication of critical process equipment is one of the most common causes of equipment‐related problems. In some cases, the reason for misapplication is poor design, but more often it results from uncontrolled modifications or changes in the operating requirements of the machine.
Management Systems
The common root causes of management system problems are policies and procedures, standards not used, and employee relations, inadequate training, inadequate supervision, wrong worker selection etc. Most of this potential root causes deal with plant culture and management philosophy. While hard to isolate, the categories that fall within this group of causes contribute to many of the problems that will be investigated. Many SOPS used to operate critical plant production systems are out of date or inadequate. This often is a major contributor to reliability and equipment‐related problems. Training or inadequate employee skills commonlycontribute to problems that affect plant performance and equipment reliability. The reasons underlying inadequate skills vary depending on the plant culture, workforce, and a variety of other issues.
Identify Possible Causal Factors
What Is a Causal Factor?
A causal factor can be defined as any “major unplanned, unintended contributor to an incident (a negative event or undesirable condition), that if eliminated would have either prevented the occurrence of the incident or reduced its severity or frequency. Also known as a critical contributing cause.”
What Is a Root Cause?
A root cause is “a fundamental reason for the occurrence of a problem or event.” Analysts can look for the root cause of an event in order to prevent it from happening again in the future. The root cause is the primary driver of a process.
What Is the Difference Between a Causal Factor and a Root Cause?
The causal factor isn’t the single factor that drove the event. Instead, a causal factor was one of a few influences. The event could still occur again or would have happened without the causal factor. In fact, during a root cause analysis, analysts often use techniques called the “5 whys,” fish bone diagram, fault tree analysis etc to identify multiple causal factors until they find a root cause of an event. Put simply, the root cause is the primary driver of the event and causal factors are secondary or tertiary drivers.
During this stage, identify as many causal factors as possible. Too often, people identify one or two factors and then stop, but that's not sufficient. With RCA, you don't want to simply treat the most obvious causes – you want to dig deeper.
What sequence of events leads to the problem?
What conditions allow the problem to occur?
What other problems surround the occurrence of the central problem?
The Five Whys
The Five Whys is a simple problem‐solving technique that helps to get to the root of a problem quickly. The Five Whys strategy involves looking at any problem and drilling down by asking: “Why?” or “What caused this problem?” Invented in the 1930s by Toyota Founder Kiichiro Toyoda’s father Sakichi and made popular in the 1970s by the Toyota Production System, the 5 Whys strategy involves looking at any problem and asking:
“Why?” and “What caused this problem?”
The idea is simple. By asking the question, “Why” you can separate the symptoms from the causes of a problem. This is critical as symptoms often mask the causes of problems. As with effective incident classification, basing actions on symptoms is worst possible practice. Using the technique effectively will define the root cause of any non‐conformances and subsequently lead you to defining effective long‐term corrective actions.
While you want clear and concise answers, you want to avoid answers that are too simple and overlook important details. Typically, the answer to the first “why” should prompt another “why” and the answer to the second “why” will prompt another and so on; hence the name Five Whys. This technique can help you to quickly determine the root cause of a problem. It's simple and easy to learn and apply.
The 5‐Why analysis is the primary tool used to determine the root cause of any problem. It is documented in the Toyota Business Process manual and practiced by all associates.
When to Use 5 Why
When the problem and root cause is not immediately apparent When you want to prevent the problem from occurring in the future.
Ask yourself, “Will implementing the Systemic Corrective Action prevent the next failure?” If the answer is “NO,” you must understand the deeper WHY.
If human error is identified, you must understand why the human committed the error. What management controlled factor impacted performance? What system must change to eliminate (or significantly reduce) the chance for error? “Training the Operator” is rarely the best response.
Why was the operator not trained properly? Why was the training not effective? What environmental factors caused the operator to not do his/her best work? Did he/she have to go around the system due to other issues or pressures? Can the system be error‐proofed? All root cause analysis must include a look at the associated Management Systems For virtually every incident, some improvement(s) in the Management Systems could have prevented most (or all) of the contributing events – ASQ estimates 82–86% Correct the process that created the problems.
During the 5 Why analysis, you should ask yourself if there are similar situations that need to be evaluated perform a “Look Across” the organization. If this situation could apply to multiple funds, then the corrective action must address all funds.
How to Use the 5 Whys
1 Develops the problem statement. Be clear and specific.
2 Assemble a team of people knowledgeable about the processes and systems involved in the problem being discussed. They should have personal knowledge about the non‐conformance of the system.
3 On a flip chart, presentation board, or even paper; write out a description of what you know about the problem. Try to document the Problem and describe it as completely as possible. Refine the definition with the team. Come to an agreement on the definition of the Problem at hand.
4 The team facilitator asks why the problem happened and records the team response. To determine if the response is the root cause of the problem, the facilitator asks the team to consider “If the most recent response were corrected, is it likely the problem would recur?” If the answer is yes, it is likely this is a contributing factor, not a root cause.If the answer provided is a contributing factor to the problem, the team keeps asking “Why?” until there is agreement from the team that the root cause has been identified.It often takes three to Five Whys, but it can take more than five! So keep going
