EHS Management

Dig Deeper: Four Steps to Determine the Root Cause

An incident investigation is completed after something has gone wrong, so it may feel a little unnatural to think of it as a preventive tool—but that’s exactly what it is. The purpose of investigating something that has already happened is primarily to understand what went wrong—and make sure that it doesn’t happen again. In the case of near misses and close calls, part of the purpose is to make sure not only that it doesn’t happen again, but that it’s not much worse the next time.

In order to best prevent incidents, the Occupational Safety and Health Administration (OSHA) and the U.S. Environmental Protection Agency (EPA) both recommend that employers use an investigative technique called “root cause analysis.” This type of investigation follows a systems approach, working from the principle that the root causes of an incident can be traced back to failures of the programs that manage safety and health in the workplace.

A Four-Step Systems Approach

In September 2016, in a fact sheet jointly published with the EPA, both agencies again urged the root cause approach on employers, in particular, employers subject to incident investigation requirements under the process safety management (PSM) or risk management program (RMP) standards. In December 2015, OSHA published a 14 page guide, Incident (Accident) Investigations, a Guide for Employers, that details a four-step approach to root cause investigations.

Here’s how those steps dovetail with the regulatory requirements:

  1. Preserve and Document the Scene.

Both the PSM and RMP standards require that employers initiate an incident investigation within 48 hours. It’s important to being an investigation quickly, while the evidence is fresh—including the memories of any individuals who might have information about what happened. The first step in the investigation is to preserve as much of that evidence as possible and prevent it from being removed or altered.

Both the PSM and the RMP standards also require that the investigation report include the date of the incident, the date the investigation began, and a description of the incident. That information will be gathered in this stage. Include documentation of who is conducting the investigation; both standards require that the incident investigation team include at least one person knowledgeable in the process involved, including a contract employee if the incident involved work of the contractor, and other persons with appropriate knowledge and experience to thoroughly investigate and analyze the incident.

In addition, make sure that you record name(s) of any injured employees and a description of their injury or injuries; whether the injured workers are temporary or permanent; and the location of the incident. Document the scene with both verbal and visual descriptions—maps and diagrams, as well as images and video, if possible.

  1. Collect Information.

The investigation must determine the factors that contributed to the incident, and in part this is determined through the collection of information. Interviews are a key source of information, and naturally the scene itself will provide clues, but relevant information may also come from:

  • Equipment manuals
  • Industry guidance documents
  • Company policies and records
  • Maintenance schedules, records, and logs
  • Training records (including communication to employees)
  • Audit and follow‐up reports
  • Enforcement policies and records
  • Previous corrective action recommendations
  1. Determine Root Causes

The investigation should get at the underlying reasons why the incident occurred—the root causes. According to OSHA, the way to effectively determine root causes is to keep asking “why?” The proximate cause of the accident—for example, “the worker used the wrong tool”—does not generally provide the answer that will prevent a recurrence of the incident. Why did the worker use the wrong tool? Was the right tool unavailable? Why? Did the worker not know the correct tool to use? Why? Did the worker decide that getting the right tool would take too long? Why?

When the investigation digs deep enough to find the management, design, planning, organizational and/or operational failing that lead to the incident, the root cause has most likely been identified, and the investigation can proceed to the final step:

  1. Implement Corrective Actions

When an investigation is superficial, the fix may appear easy: “Remind employees to always use the right tool.” Such solutions may not, in fact, address the system-level failures that lead the worker to use the wrong tool in the first place. Referring to our example above, what system level failures could cause a worker to use the wrong tool for a job? Examples could include:

  • Training failures: was the worker taught which tool to use?
  • Staffing failures: did the worker use the wrong tool because he was trying to do something that was not, in fact, his job—but understaffing meant that the correct person was not available to do the job?
  • Procurement failures: was the right tool unavailable because no one had purchased it?

Root causes generally require program level solutions that must be signed off on by senior management.

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