Human factors issues occur in everyday life, from when we struggle to use a hi-fi controller to starting the car, and they are thus part of life and because of this they influence what we do and how we do it.

In this post I hope to lay out the basic principles of human factors concepts in a language that we can all understand and by the use of examples in our own industry show how they can be applied to the pilotage task.

What then are human factors?

Definitions of human factors abound in many publications but my definition would be the practise of applying principles of human characteristics to the workplace.

These human characteristics include our:

• Abilities,
• Limitations,
• Patterns of error, and
• Patterns of behaviour from the individual, team and organisational viewpoint.

The science of Human Factors when applied in the workplace is useful for the:

• Design of tools and equipment,
• Specifying of jobs,
• Writing of procedures
• Creation of the workplace.

Main Goals of Human Factors

The four main goals of the field of Human Factors are:

1. Reducing errors, for example the provision of all essential information required for the pilotage task will help to reduce errors.
2. Increasing productivity, for example providing portable pilotage units may help in cutting down berthing / unberthing times.
3. Enhancing safety, for example the use of suitable passage plans will help foster a good bridge management focus.
4. Enhancing comfort, for example the redesigning of a roster may reduce fatigue. (Wickens et al., 2004)

A Simple Human Factors Model: The SCHELL Model

To further help us in our understanding of human factors it is “useful to construct a simple model” (Hawkins, 1997). This model known as the SHEL model is now extensively used and was originally designed by Edwards in 1972. Originally SHEL stood for Software, Hardware, Environment, and Liveware but over the years has been modified to include Culture and Liveware (Others) (Nendick, 2001)

The SCHELL model is shown in the figure below and as can be seen the Liveware (Individual) is at the centre of the model and the other components interact accordingly.

Source: Dr Matthew Thomas

Brief description of the other SCHELL components:

Software includes the non-physical aspects of the system such as procedures, computer software and checklists (Hawkins, 1997) for example pilotage passage plans.

Culture deals with the areas in which the people and systems are working, including the tacit acknowledgement of “accepted” practices beyond standard operating procedures and attitudes such as getting the job done or following perceived peer pressures about the norms of how things should be done (Nendick, 2001). Was this “getting the job done” culture a factor in the case of the Port Phillip Sea Pilot when he stated that he felt the “need to bring the cargo into the wharf”? Not according to the judge (Judge S. Davis, 2006).

National, professional and organisational cultures also fall under this category.

Hardware is what is being used, for example portable pilotage positioning units and includes equipment design.

Environment is where people are working for example carrying out night pilotages in shallow channels.

Liveware (Others) is the interface between people (Ames Research Center NASA, 2005) and includes issues such as communication and group performance.

A Case Study Using the SCHELL Model:

The ATSB Transport Safety Investigation Report into the grounding of the Crimson Mars can be used to show how the SCHELL model works in identifying how the system broke down resulting in the grounding.

Software: Throughout the report numerous references are made to the failure or non-existence of suitable procedures for dealing with this grounding. These references included:

1. Lack of contingency planning
2. Lack of procedures regarding the use of mobile phones
3. An unsuitable passage plan that did not interface well with the ship’s passage plan
4. The Crimson Mars Safety Management System fails to ensure that the response by the ship’s crew is effective and safe.(Australian Transport Safety Bureau, 2007).

Cultural: The bridge team were operating in a culture which whilst not actually causing the grounding certainly did nothing to assist in taking effective avoiding action. In understanding why this culture existed and why the pilot showed a “lack of cultural awareness” (Australian Transport Safety Bureau, 2007) reference should be made to Hoftstedes work in cultural dimensions in regards to individualism: Australia after the United States is the most individualistic nation in the world, whereas the Philippines follow collectivism in that the group help each other. The % rates between the countries are quite disparate (Australia 90%, Philippines 35%) and obviously Australians will speak out if things are not going according to plan. (Hofstede, 2006) It is possibly not in the cultural makeup of the Philippine crew to do this.

Hardware: The positioning of the rudder indicator and the conning positions made it difficult to see that the correct helm orders were in fact being carried out and as the report states “the rudder angle indicator should be readable from a position taken whilst conning a ship.” (Australian Transport Safety Bureau, 2007)

This ship had two additional conning positions A and E (shown in figure 2) and the pilot at the time of the incident was using position A from where it was impossible to see the rudder angle indicator. This is shown in figure 3.

Figure 2: Crimson Mars Bridge Layout

Source: (Australian Transport Safety Bureau, 2007)

Figure 3: View from position A conning position

Source: (Australian Transport Safety Bureau, 2007)

Environment: The environment of the bridge and what is going on around you can be such as to interfere with the bridge team’s situation awareness. To help in this requires “a common mental model of what ‘should’ happen during the passage.” (Australian Transport Safety Bureau, 2007) This shared mental model should have occurred during the initial master / pilot information exchange, but as that was minimal then so was the shared mental model.

The pilot answering his mobile phone also would have switched his attention away from his mental model and led to degradation in his situation awareness.

Liveware (Others): Continual poor communication between the pilot and the rest of the bridge team led to individual actions (including those of the pilot) being poorly monitored by the team.

As can be seen the SCHELL Model is useful in seeing where the system breaks down and figure 4 shows what can be the consequences when they do.

Figure 4: The consequences of when the system breaks down.

Source: (Australian Transport Safety Bureau, 2007)

In conclusion, by using Human Factors perspectives in our pilotage task there is great potential to enhance system safety as they help us to understand the complex relationships that can exist between the components, which in turn enables us to see potential errors and thus design appropriate risk mitigation strategies to avoid them.

REFERENCES:

AMES RESEARCH CENTER NASA (2005) SHEL MODEL. Patient Safety Feedback, 4, 2.

AUSTRALIAN TRANSPORT SAFETY BUREAU (2007) Independent investigation into the grounding of the Singapore registered woodchip carrier Crimson Mars in the River Tamar, Tasmania on 1 May 2006. Civic Square, Canberra, Australian Transport Safety Bureau.

HAWKINS, F. H. (1997) Human Factors in Flight. IN ORLADY, H. W. (Ed.) Human Factors in Flight. Second ed. Aldershot, Ashgate Publishing Limited.

HOFSTEDE, G. (2006) Geert Hofstede Cultural Dimensions Resources

http://www.geert-hoftstede.com/geerthofstederesources.shtml.

JUDGE S. DAVIS (2006) Victorian Civil and Administrative Tribunal Reference Number B46/2006.

NENDICK, M. (2001) What went wrong? Hot Wheels. Flight Safety Australia, July-August, 12-14.

WICKENS, C. D., LEE, J. D., LIU, Y. & GORDON-BECKER, S. E. (2004) An Introduction to Human Factors Engineering, Upper Saddle River, New Jersey, Pearson Prentice Hall.