Situation awareness


Situation awareness or situational awareness, often abbreviated as SA is the understanding of an environment, its elements, and how it changes with respect to time or other factors. It is also defined as the perception of the elements in the environment considering time and space, the understanding of their meaning, and the prediction of their status in the near future. It is also defined as adaptive, externally-directed consciousness focused on acquiring knowledge about a dynamic task environment and directed action within that environment.
Situation awareness is recognized as a critical foundation for successful decision making in many situations, including the ones which involve the protection of human life and property, such as law enforcement, aviation, air traffic control, ship navigation, health care, emergency response, military command and control operations, transmission system operators, self defense, and offshore oil and nuclear power plant management.
Inadequate situation awareness has been identified as one of the primary causal factors in accidents attributed to human error. According to Endsley's situation awareness theory, when someone meets a dangerous situation, that person needs an appropriate and a precise decision-making process which includes pattern recognition and matching, formation of sophisticated frameworks and fundamental knowledge that aids correct decision making.

Definition

The formal definition of situational awareness is often described as three ascending levels:
  1. Perception of the elements in the environment,
  2. Comprehension or understanding of the situation, and
  3. Projection of future status.
People with the highest levels of situational awareness not only perceive the relevant information for their goals and decisions, but are also able to integrate that information to understand its meaning or significance, and are able to project likely or possible future scenarios. These higher levels of situational awareness are critical for proactive decision making in demanding environments.
Three aspects of situational awareness have been the focus in research: situational awareness states, situational awareness systems, and situational awareness processes. Situational awareness states refers to the actual level of awareness people have of the situation. Situational awareness systems refers to technologies that are developed to support situational awareness in many environments. Situational awareness processes refers to the updating of situational awareness states, and what guides the moment-to-moment change of situational awareness.

History

Although the term itself is fairly recent, the concept has roots in the history of military theory—it is recognizable in Sun Tzu's The Art of War, for example. The term can be traced to World War I, where it was recognized as a crucial skill for crews in military aircraft.
There is evidence that the term situational awareness was first employed at the Douglas Aircraft Company during human factors engineering research while developing vertical and horizontal situation displays and evaluating digital-control placement for the next generation of commercial aircraft. Research programs in flight-crew computer interaction and mental workload measurement built on the concept of awareness measurement from a series of experiments that measured contingency awareness during learning, and later extended to mental workload and fatigue.
Situation awareness appears in the technical literature as early as 1983, when describing the benefits of a prototype touch-screen navigation display. During the early 1980s, integrated "vertical-situation" and "horizontal-situation" displays were being developed for commercial aircraft to replace multiple electro-mechanical instruments. Integrated situation displays combined the information from several instruments enabling more efficient access to critical flight parameters, thereby improving situational awareness and reducing pilot workload.
The term was first defined formally by Endsley in 1988. Before being widely adopted by human factors scientists in the 1990s, the term is said to have been used by United States Air Force fighter aircrew returning from war in Korea and Vietnam. They identified having good situation awareness as the decisive factor in air combat engagements—the "ace factor". Survival in a dogfight was typically a matter of observing the opponent's current move and anticipating his next move a fraction of a second before he could observe and anticipate it himself.
USAF pilots also came to equate situational awareness with the "observe" and "orient" phases of the famous observe-orient-decide-act loop, or Boyd cycle, as described by the USAF war theorist Col. John Boyd. In combat, the winning strategy is to "get inside" your opponent's OODA loop, not just by making one's own decisions quicker, but also by having better situation awareness than one's opponent, and even changing the situation in ways that the opponent cannot monitor or even comprehend. Losing one's own situation awareness, in contrast, equates to being "out of the loop".
Clearly, situational awareness has far reaching applications, as it is necessary for individuals and teams to function effectively in their environment. Thus, situational awareneas has gone far beyond the field of aviation to work being conducted in a wide variety of environments. Situation awareness is being studied in such diverse areas as air traffic control, nuclear power plant operation, emergency response, maritime operations, space, oil and gas drilling, vehicle operation, and health care.

Theoretical model

Endsley's Cognitive Model of SA

The most widely cited and accepted model of SA was developed by Dr. Mica Endsley, which has been shown to be largely supported by research findings. Lee, Cassano-Pinche, and Vicente found that Endsley's Model of SA received 50% more citations following its publication than any other paper in Human Factors compared to other papers in the 30 year period of their review.
Endsley's model describes the cognitive processes and mechanisms that are used by people to assess situations to develop SA, and the task and environmental factors that also affect their ability to get SA. It describes in detail the three levels of SA formation: perception, comprehension, and projection.
Perception : The first step in achieving SA is to perceive the status, attributes, and dynamics of relevant elements in the environment. Thus, Level 1 SA, the most basic level of SA, involves the processes of monitoring, cue detection, and simple recognition, which lead to an awareness of multiple situational elements and their current states.
Comprehension : The next step in SA formation involves a synthesis of disjointed Level 1 SA elements through the processes of pattern recognition, interpretation, and evaluation. Level 2 SA requires integrating this information to understand how it will impact upon the individual's goals and objectives. This includes developing a comprehensive picture of the world, or of that portion of the world of concern to the individual.
Projection : The third and highest level of SA involves the ability to project the future actions of the elements in the environment. Level 3 SA is achieved through knowledge of the status and dynamics of the elements and comprehension of the situation, and then extrapolating this information forward in time to determine how it will affect future states of the operational environment.
Endsley's model shows how SA "provides the primary basis for subsequent decision making and performance in the operation of complex, dynamic systems". Although alone it cannot guarantee successful decision making, SA does support the necessary input processes upon which good decisions are based.
SA also involves both a temporal and a spatial component. Time is an important concept in SA, as SA is a dynamic construct, changing at a tempo dictated by the actions of individuals, task characteristics, and the surrounding environment. As new inputs enter the system, the individual incorporates them into this mental representation, making changes as necessary in plans and actions in order to achieve the desired goals.
SA also involves spatial knowledge about the activities and events occurring in a specific location of interest to the individual. Thus, the concept of SA includes perception, comprehension, and projection of situational information, as well as temporal and spatial components.
Endsley's model of SA illustrates several variables that can influence the development and maintenance of SA, including individual, task, and environmental factors.
In summary, the model consists of several key factors that describe the cognitive processes involved in SA:
  • Perception, comprehension, and projection as three levels of SA,
  • The role of goals and goal directed processing in directing attention and interpreting the significance of perceived information,
  • The role of information salience in "grabbing" attention in a data-driven fashion, and the importance of alternating goal-driven and data-driven processing,
  • The role of expectations in directing attention and interpreting information,
  • The heavy demands on limited working memory restricting SA for novices and for those in novel situations, but the tremendous advantages of mental models and pattern matching to prototypical schema that largely circumvent these limits,
  • The use of mental models for providing a means for integrating different bits of information and comprehending its meaning and for allowing people to make useful projections of likely future events and states,
  • Pattern matching to schema—prototypical states of the mental model—that provides rapid retrieval of comprehension and projection relevant to the recognized situation and in many cases single-step retrieval of appropriate actions for the situation.
The model also points to a number of features of the task and environment that affect SA:
  • The capability of the system and the user interface for conveying important information to the person in a way that is easy to integrate and process.
  • Both high workload and stress can negatively affect SA. Information overload is a problem in many situations.
  • Underload can also negatively affect SA.
  • The complexity of the systems and situations a person is in can negatively affect SA by making it difficult to form accurate mental models.
  • Automation is a major factor reducing situation awareness in many environments. See out of the loop performance problems. This is due to it creating situations where people are forced to become monitors which they are poor at, often poor system transparency with needed information not provided, and an overall reduction in the level of cognitive engagement of people with automated systems.
Experience and training have a significant impact on people's ability to develop SA, due to its impact on the development of mental models that reduce processing demands and help people to better prioritize their goals. In addition, it has been found that individuals vary in their ability to acquire SA; thus, simply providing the same system and training will not ensure similar SA across different individuals. Research has shown that there are a number of factors that make some people better at SA than others including differences in spatial abilities and multi-tasking skills.