Human Factors

By John Kidwell

What is it?
The study of Human Factors is concerned with making a closer fit between people and the environment where people live and work. A practitioner of this discipline works to design and modify products, settings, and tasks to the physical, perceptual, and cognitive characteristics and limitations of those who will be using them. Done correctly, the result should be fewer errors and injuries and people should perform tasks more effectively and efficiently.

Historical significance
The Human Factors discipline was conceived during the Second World War when the costs of human error were particularly unacceptable. The military gathered psychologists, engineers, physicians, and experts from several disciplines to improve human performance. The teams' initial attempts to improve human reliability were primarily traditional (e.g., better techniques for selecting personnel, better training methods, better incentives, and even the use of drugs to enhance vigilance). Consequently, many of these approaches did improve human performance, but the improvements were typically short-lived. At this point the suggestion was made to shape the system to the characteristics of the operator instead of trying to shape the operator to the characteristics of the system. This ideological swing marked the surfacing of the Human Factors discipline in the United States.

The evidence abounds
In August 1963, the Secretary of the Treasury's Committee on Tanker Hazards reported that "safety problems relate more to personnel than to materiel." In a more recent study, the U.S. Coast Guard (1994) recognized that roughly 80% of all marine-related accidents are rooted in the human element---with the majority of these caused by organizational factors (Figure 1).

Figure 1. Marine Accident Root Causes

This leads to the conclusion that even with advanced ship construction and modern technology, there is still a strong likelihood that maritime accidents will occur. To this point, the U. S. Coast Guard began taking a more active approach to improve the focus on human elements, not just to reduce casualties and protect the environment, but to also provide greater efficiency and reliability to the industry.

Lessons learned
As Commanding Officer of Northeast Region Fisheries Training Center located in Cape Cod, MA, Lieutenant (LT) J. W. Summerlin is a lead investigator of maritime accidents for the Coast Guard. He agrees with the above research and goes on to state, "When a system fails, the investigation tends to point out equipment, management or technology as the failure point. When in actuality, I find people are in the equation almost every time." For example, a vessel's technological capabilities might exceed industry standards, but if management doesn't ensure that mariners are trained and experienced in using technology, casualties may still occur.

Motor Vessel Royla Majesty

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Figure 2: Motor Vessel Royal Majesty

Take, for example, the grounding of Motor Vessel (M/V) Royal Majesty during the summer of 1996 (Figure 2). Transiting off the Coast of Nantucket Island, MA, the ship ran aground in 11 feet of water. Although the ship was technologically well equipped, Figure 2: Motor Vessel Royal Majesty
the ship's autopilot malfunctioned-sending it off course. The ensuing investigation yielded 2 major contributing factors: 1) the crew's overconfidence in the ship's computer guidance, and 2) indicator alarm lights poorly placed out of view. Not surprisingly, both factors are products of human error: behavior and design.

Piper Alpha

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Figure 3: Piper Alpha

In July 1988, 165 people lost their lives on a oil drilling platform in the North Sea (Figure 3). The Piper Alpha suffered a gas compression module explosion that quickly engulfed the entire platform. The large loss of life was primarily attributed to poor evacuation procedures, poor design of decks and ladders (stairways) and the inability of personnel to visually check equipment status (poor design). Again, all were products of human error.

Changes in design
Human Factors practitioners have played a supportive role with the maritime industry toward making huge strides in dealing with the same problems that were found aboard the M/V Royal Majesty and the Piper Alpha. For example, vessels are now equipped with highly visible indicator lights / alarms and equipment (including decks and floors) is more ergonomically designed to lessen crew fatigue. For platforms, evacuation plans are now better designed / marked in high visibility areas and stairways have been widened to accommodate varied foot sizes. All corrections can drastically reduce the impact of maritime accidents due to human error. In the words of LT Summerlin, "To make additional significant, cost-effective gains in safety, the marine community can't just advance technology; it must also integrate technology around the people who employ it."


U.S. Coast Guard. (1994). Marine casualty investigation and reporting: Analysis and recommendations for improvement. U.S. Coast Guard Research and Development Center, Groton, CT.

Ship Structure Committee. (1994). The role of human error in design, construction, and reliability of marine structures. Washington, DC.

Author Note


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