BY

CHARLES BARBEE & DAVID DEAVER

The most basic element of conducting a marine investigation is telling the story of what happened. During the initial stages of every investigation, marine investigators should gather and record all the facts that may assist in determining causes. They should be aware of the dangers of reaching conclusions too early, thereby failing to keep an open mind in order to consider the full range of possibilities. It is recommended that the fact-finding step of the marine investigation process be kept separate from the analysis of the collected evidence leading to conclusions and recommendations. The objective of the fact-finding step of the investigation is to collect as many facts as possible regarding the incident and the actions/events/conditions surrounding it. The scope of any Investigation can be divided into five areas: people (liveware); environment; equipment (hardware); and procedures (software).

The factual information that is gathered will be classified into three category types. They are:

　

□ Actions: Things people do. The master agreed to passing arrangements with the other vessel.

□ Events: Things that happen. The vessel went aground.

□ Condition: Existing circumstances or state of being. The shaft bearing was missing a safety guard.

This is the chronological ordering of what occurred. This is where the marine investigator determines the order with regard to who did what, what happened, or what condition existed at a particular time or over a period of time. This is the information that generates measurable data from which trends and preventative measures may be derived.

The SHEL model was developed by Elwin Edwards and refined by Captain Frank Hawkins as an investigation tool that allows a marine investigator to explore the interaction of the many operational parts of the maritime transportation system. The model effectively moves the focus from the individual (mariner) to the system. Rather than focusing on any single element in the system, it assumes that any failure in the system results from a mismatch between two or more of its components. The IMO has suggested the SHEL model as a means for exploring the interaction of all parts of the maritime transportation system in an accident, and the Coast Guard has adopted it as the principal means of conducting on-scene fact-finding. The SHEL Model is a categorization of the various conditions that the marine investigator may wish to record.

The SHEL model suggests that all of the operational elements of the maritime transportation system belong to one of four categories. Accordingly, the marine investigator should observe the condition of the various elements in those four categories. These categories are simply:

　

□ Software: The information and support systems guiding people.

Software elements include checklists, manuals, publications, procedures, regulatory requirements, training, education, maps, and charts.

□ Hardware: The vessels, facilities, machinery, cargo, equipment, and materiel people work with. Hardware elements include all machinery, gear, electronics, switches, controls, and displays.

□ Environment: The internal and marine environment in which people work. Environment elements include the internal environment such as workplace environment, room temperature ventilation, lighting, pitching and yawing, and the marine environment such as sea state, wind, ice, precipitation, and visibility.

□ Liveware: The people themselves. Liveware elements include all of the people involved in the incident both directly and indirectly.

　

The SHEL model is typically depicted graphically to display not only the four categories or components of the maritime transportation system, but also the relationships or interfaces" between the elements and the people (liveware) at the heart of the model.

　

The central component of the SHEL model is a person. That person interacts with the other components of the maritime transportation system, and is influenced by mismatches in those interactions. The person is also influenced, however, by factors entirely within themselves that they bring into the maritime transportation system. Such factors to be explored in using the SHEL model include physical factors (height, weight, strength, etc.), physiological factors (health, drug and alcohol use, fatigue, nutrition, medical conditions, etc.), psychological factors (personality, attitude, biases, etc.), and psychosocial factors (personal relationships, marital difficulties, money problems, etc.). When collecting information about an incident, marine investigators should limit their in-depth examination to those people who were directly involved in the accident. Pursuant to the rules in Title 46 CFR Part 4, post-casualty drug and alcohol testing should be performed on people directly involved in a marine casualty, when required. Similarly, a 96-hour work/rest history should always be gathered for that person as well. The lists below contain the various areas of examination of liveware. The lists are not exhaustive.

　

Physical Capability. The physical capability of the individual to perform required actions and movements. Consider:

Sensory Limitations. The sensory limitations of the individual that may affect the person's performance. Consider:

　

Nutrition Factors. Nutrition potentially affects an individual's ability to respond to action or resist fatigue. Consider:

Health Factors. Health factor can directly aff