The LMQ definition of Human Factors which has been adopted by many organisations in several high risk industries is:-
‘Anything that affects a person’s performance’.
Crew Resource Management falls under the overall human factors umbrella, and can be considered as a technique for managing some of these issues. The LMQ human factors model uses this basic idea as a way of understanding human performance and how we can influence it. It comprises four elements:
Performance Direct Factors Managing Factors Potential Factors.
The model is headed by performance, which is a workable term for the output of a human being at work. Most of the time this performance is fairly standard; occasionally it is better than that and also occasionally it is below standard, or what is often called error. However, it is error with which we are generally most concerned, and which provides the motivation for change, so we will use error as the example for describing the remainder of the model.
The consequences arising from a particular level of performance could be considered irrelevant because other uncontrollable factors are involved. In other words, if a person drives through a red light, which is an error or below standard performance, there may or may not be an accident – depending on whether another vehicle or person happens to arrive at the same spot. The important thing to do is to identify why the error occurred and how to prevent it happening in future, without being overly influenced by the consequences.
The next section of the model are the Direct Factors, which are those acts or omissions that directly and immediately affect performance.
There are four Direct Factors:
Decision – The quality of the decision making.
Dexterity – The amount of physical or mental dexterity.
Awareness – The level of awareness.
Distraction – The level of concentration or amount of distraction.
In almost every case where a person has performed below standard or made an error, it is either due to a poor decision, a lack of physical or mental dexterity, a distraction, or a lack of awareness (which includes forgetting).
Take the above example of the driver who goes through a red light, which is an ‘error’ level of performance. This might be because the driver:
Has intentionally decided to go through the red light (decision). Pressed the accelerator instead of the brake (dexterity).
Did not notice that the light was red (awareness).
Knew it was red but was distracted and forgot to stop (distraction).
Another example of an error would be if an aircraft continued an approach below minima and still in cloud. This might be because the pilot:
Made the decision to continue because the previous aircraft had made it (decision).
Applied power but did not pitch up (dexterity).
Thought the MDA/DH was 450ft rather than 550ft (awareness).
Got a malfunction caution just before MDA/DH (distraction).
Therefore, a good starting point for investigating human error might be to identify which of these Direct Factors were directly involved in the making of the error. There may be situations where a combination of these Direct Factors is involved. For instance, a pilot may decide to continue an approach below minima, but then lost altitude while busy searching for the runway lights, was momentarily distracted and hit the trees on the ridge that he or she was unaware were there.
Conversely, sound decision making, better mental or physical dexterity, a high level of concentration and good awareness will have a direct effect on an improved level of performance.
One reason why it is important to identify which of the Direct Factors were involved in the error is that it enables the issue of blame to be better managed at an early stage. The only Direct Factor that could warrant blame to be considered is if the error was as a result of a fully informed decision and therefore intentional. Error as a result of a lack of awareness, distraction or dexterity requires further investigation if blame is to be attributed correctly.
When professionals recognise that these are the direct causes of error, not only can they better understand how their training and the other factors fit into the equation, but they are also alerted in times of stress to be extra-vigilant and cross check other members of their team.
The Potential Factors are the everyday plethora of hurdles that we all are faced with when going about our business, but which significantly affect our propensity to make errors or not perform at our best. Professor James Reason refers to these as latent errors, and the only difference we make is that we classify Potential Factors as those that are typically outside our influence. These factors create the conditions for accidents to occur but they are not in themselves the causes of accidents. Many successful outcomes have been achieved in spite of the existence of these factors. We can do little about many of these factors such as the environment, but what we can do is minimise their impact. This can be done directly, or by equipping people with better Managing Factors (described below).
We can classify Potential Factors several ways, but to keep it simple let’s just put them into 4 areas.
Tangible external (to the pilot):
Weather, technical failures, design, documentation, temperature etc.
Relationships, commercial pressures, financial, culture etc
Illness, fatigue, stress, drugs etc
Disorientation, fixation, visual illusions, denial, memory etc
Of the above, one of the most significant Potential Factors is the commercial pressures that aircrew face today, and the major training problem is that these cannot be replicated using the flight simulator, the main training resource.
The final part of the model are the Managing Factors, which provide a buffer between the Potential Factors and the Direct Factors. These are the knowledge, skills and attitudes of individuals which not only can improve the Direct Factors, such as making better decisions, improving dexterity, avoiding distraction and being more aware; but which also more effectively manage the Potential Factors. They also include checklists, SOPs and good systems. It is here that CRM plays its part.
They can be divided into things that the organisation can do and things that an individual can do.
Airmanship can be considered a collective term for most of the Managing Factors that are under an individual’s control.
Dividing the way performance is affected into these three distinct elements has the following advantages:
It highlights where resources should be prioritised and where changes need to be made. In other words, identifying if the error was more due to a breakdown in the Managing Factors or because of a Potential Factor such as poor design.
It enables the investigation of accidents and incidents to be more structured so that the network of causes is more easily understood. It moves the investigation away from blame or finding out who was at fault, and more into identifying objectively what happened and why.
It enables preventative actions to be better structured and appropriate, and avoids duplication such as unnecessary ‘belt and braces’ activities that can cause further problems.
If performance is to be improved then both the Managing Factors need to be improved and the threat from Potential Factors minimised. This will then translate into the Direct Factors – better decision making, improved mental and physical dexterity, better concentration and improved awareness producing a higher level of performance and less error.
A complete power point presentation of the LMQ Human Factors Model is freely available in the Download section Downloads