Root Cause Analysis is a useful process for understanding and solving a problem. It supports companies to figure out what negative events are occurring. Then to look at the complex systems around those problems, and identify key points of failure. Finally, companies are able to determine solutions to address those key points, or root causes.

As an analytical tool, Root Cause Analysis is an essential way to perform a comprehensive, system-wide review of significant problems as well as the events and factors leading to them.

If you only fix the deficiency (already identified) then the problem will almost certainly happen again, which will lead you to fix it, again, and again, and again.

If, instead, you look deeper to figure out why the problem is occurring, you can fix the underlying systems and processes that cause the problem.

Root Cause Analysis (RCA) is a technique that helps you answer the question of why the problem occurred in the first place.

Root Cause Analysis aims to identify the origin of a problem. It uses a specific set of steps to find the primary cause of the problem, so that you can:

1. Determine what happened.

2. Determine why it happened.

3. Figure out what to do to reduce the likelihood that it will happen again.

RCA assumes that systems and events are interrelated. An action in one area causes an action in another, and another, and so on. By following back these actions, you can discover where the problem started and how it grew into the issue you are now facing.

You will usually find three basic types of causes:

1. Physical causes – Tangible, material items failed in some way (for example, a water ingress alarm stopped working).

2. Human causes – People did something wrong, or did not doing something that was needed. Human causes typically lead to physical causes (for example, no one checked the alarm circuit, which led to the sensor failing).

3. Organisational causes – A system, process, or policy that people use to make decisions or do their work is faulty (for example, no one person was responsible for sensor maintenance, and everyone assumed someone else had checked).

Root Cause Analysis looks at all three types of causes. It involves investigating the patterns of negative effects, finding hidden flaws in the system, and discovering specific actions that contributed to the problem. This often means that RCA reveals more than one root cause.

You can apply Root Cause Analysis to almost any situation. Determining how far to go in your investigation requires good judgement and common sense. Theoretically, you could continue to trace root causes back to the Stone Age, but the effort would serve no useful purpose. Be careful to understand when you've found a significant cause that can, in fact, be changed.

The Root Cause Analysis Process

Root Cause Analysis has five identifiable steps.

Step One: Define the Problem

Step Two: Collect Data

You need to analyse a situation fully before you can move on to look at factors that contributed to the problem. To maximise the effectiveness of your Root Cause Analysis, consult everyone (Superintendents, Ship’s staff, Authorities) who understand the situation. People who are most familiar with the problem can help lead you to a better understanding of the issues.

Step Three: Identify Possible Causal Factors

During this stage, identify as many contributing factors as possible. Too often, people identify one or two factors and then stop, but that is not sufficient. With RCA, you don't want to simply treat the most obvious causes – you want to dig deeper.

Use these tools to help identify contributing factors:

Step Four: Identify the Root Cause(s)

Use the same approach as in Step Three to look at the roots of each factor. This is intended to encourage you to dig deeper at each level of cause and effect.

Step Five: Recommend and Implement Solutions

Analyse your cause-and-effect process, and identify the changes needed for various systems. It's also important that you plan ahead to predict the effects of your solution. This way, you can spot potential failures before they happen.

It is worthy noting that the above three types of causes – are by “location” of the failure in the chain of happenings/conditions prior to the incident in question. Causes also differentiate by their place in the chain of events, causes are immediate, underlying (intermediate) and root (basic) causes.

E. g. immediate cause of a mooring line parting is the force applied to the line did exceed its breaking limit. This immediate cause is meaningless from prevention point of view as it provides no insight for the underlying causes and establishing and addressing root causes. Prevention of recurrence will be inadequate if root cause analysis is of insufficient depth and underlying causes are mistaken for root causes. In many cases an adverse event is the result of breaches of several safety nets, and breach of each safety net has its own root cause.

There are numerous methodologies for root cause analysis. 5 whys, Pareto Chart, Fishbone Diagram, Scatter Diagram, Affinity Diagram, Fault Tree Analysis, Comprehensive Chart of Root Causes, Comprehensive List of Causes, M-SCAT, MaRCAT are just some to mention. Each of these has its benefits and flaws and some may be better suited for a particular type of events than other ones.

While correction of the problem allows to resume operation/activity, the ultimate goal of each investigation and analysis is prevention of recurrence. Prevention is to address each found root cause and there may be more than one recurrence preventive measure for one root cause. Preventive measures addressing underlying (intermediate) causes should also be considered. Similar not directly associated problems, e. g. onboard other vessels in fleet also desire prevention.

There shall be logical connection between the recurrence prevention and root causes. Quite often in the root cause analysis preventive measures are “stand alone” with nu connection to the derived root causes. Quite often it may be seen that they seem to be correct: they are addressing apparent root causes which have been omitted from the analysis. Such omissions shall be avoided.

Preventive measures may be of different types: eliminating the hazard, improving safety nets – addressing the system/design; eliminating errors and omissions by personnel; combination of the above and allowing for and mitigating losses – the latter for unessential and not critical equipment/functions e. g. maintaining stock and changing lamps, renewing used batteries, disposable filters etc.

Further publicly available reading about requirements, investigations and root cause analysis: