Situation awareness

Situational awareness or situation awareness (SA) is the perception of environmental elements and events with respect to time or space, the comprehension of their meaning, and the projection of their status after some variable has changed, such as time, or some other variable, such as a predetermined event. It is also a field of study concerned with understanding of the environment critical to decision-makers in complex, dynamic areas from aviation, air traffic control, ship navigation, power plant operations, military command and control, and emergency services such as fire fighting and policing; to more ordinary but nevertheless complex tasks such as driving an automobile or riding a bicycle.

Situation awareness involves being aware of what is happening in the vicinity to understand how information, events, and one's own actions will impact goals and objectives, both immediately and in the near future. One with an adept sense of situation awareness generally has a high degree of knowledge with respect to inputs and outputs of a system, an innate "feel" for situations, people, and events that play out because of variables the subject can control. Lacking or inadequate situation awareness has been identified as one of the primary factors in accidents attributed to human error.^[1] Thus, situation awareness is especially important in work domains where the information flow can be quite high and poor decisions may lead to serious consequences (such as piloting an airplane, functioning as a soldier, or treating critically ill or injured patients).

As outlined below, three facets of SA have been in focus in research, namely SA States, SA Systems, and SA processes. SA States refers to the actual awareness of the situation. SA Systems refers to the distribution of SA in teams and between objects in the environment, and to the exchange of SA between system parts. SA Processes refers to the updating of SA States, and what guides the moment-to-moment change of SA.^[2]

Having complete, accurate and up-to-the-minute SA is essential where technological and situational complexity on the human decision-maker are a concern. Situation awareness has been recognized as a critical, yet often elusive, foundation for successful decision-making across a broad range of complex and dynamic systems, including aviation, air traffic control, ship navigation,^[3] health care,^[4] emergency response and military command and control operations,^[5] and offshore oil and nuclear power plant management.^[6]

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 instance. The term itself, can be traced also to World War I, where it was recognized as a crucial component for crews in military aircraft.^[7]

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^[8] and Mental Workload Measurement ^[9] built on the concept of awareness measurement from a series of experiments that measured contingency awareness during learning ^{[10] [11]} and then later to mental workload and fatigue.^[12]

Situation awareness appears in the technical literature as early as 1983 when describing the benefits of a prototype touch-screen navigation display.^[13] 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.

Before being widely adopted by human factors scientists in the 1990s, the term is said to have been used by United States Air Force (USAF) fighter aircrew returning from war in Korea and Vietnam.^[14] They identified having good SA as the decisive factor in air combat engagements—the "ace factor".^[15] 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 his own. USAF pilots also came to equate SA with the "observe" and "orient" phases of the famous observe-orient-decide-act loop (OODA 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 your own decisions quicker, but also by having better SA than the opponent, and even changing the situation in ways that the opponent cannot monitor or even comprehend. Losing one's own SA, in contrast, equates to being "out of the loop."

Clearly, SA has far reaching applications as it is needed for individuals and teams to function effectively in their environment. Thus, we are beginning to see SA going beyond the field of aviation and work being conducted in a wide variety of domains. Currently, SA is now being studied in such diverse areas as air traffic control, nuclear power plant operation, vehicle operation and anesthesiology.^{[16][17][18][19][20]}

Related concepts

Several cognitive processes related to situation awareness are briefly described in this section. The matrix shown below attempts to illustrate the relationship among some of these concepts.^[21] Note that situation awareness and situational assessment are more commonly discussed in information fusion complex domains such as aviation and military operations and relate more to achieving immediate tactical objectives.^[22][23][24] Sensemaking and achieving understanding are more commonly found in industry and the organizational psychology literature and often relate to achieving long-term strategic objectives.

		Phase
		Process	Outcome
Objective	Tactical (short-term)	situational assessment	situation awareness
	Strategic (long-term)	sensemaking	understanding
	Scientific (longer-term)	analysis	prediction

Situational understanding

Situation awareness is sometimes confused with the term "situational understanding." In the context of military command and control applications, situational understanding refers to the "product of applying analysis and judgment to the unit's situation awareness to determine the relationships of the factors present and form logical conclusions concerning threats to the force or mission accomplishment, opportunities for mission accomplishment, and gaps in information".^[25] Situational understanding is the same as Level 2 SA in the Endsley model—the comprehension of the meaning of the information as integrated with each other and in terms of the individual's goals. It is the "so what" of the data that is perceived.

Situational assessment

In brief, situation awareness is viewed as "a state of knowledge," and situational assessment as "the processes" used to achieve that knowledge. Endsley argues that "it is important to distinguish the term situation awareness, as a state of knowledge, from the processes used to achieve that state.^[26] These processes, which may vary widely among individuals and contexts, will be referred to as situational assessment or the process of achieving, acquiring, or maintaining SA." Note that SA is not only produced by the processes of situational assessment, it also drives those same processes in a recurrent fashion. For example, one's current awareness can determine what one pays attention to next and how one interprets the information perceived.^[27]

Mental models

Accurate mental models are one of the prerequisites for achieving SA.^[28][29] A mental model can be described as a set of well-defined, highly organized yet dynamic knowledge structures developed over time from experience.^[30][31] The volume of available data inherent in complex operational environments can overwhelm the capability of novice decision makers to attend, process, and integrate this information efficiently, resulting in information overload and negatively impacting their SA.^[32] In contrast, experienced decision makers assess and interpret the current situation (Level 1 and 2 SA) and select an appropriate action based on conceptual patterns stored in their long-term memory as "mental models".^[33] Cues in the environment activate these mental models, which in turn guide their decision making process.

Sensemaking

Klein, Moon, and Hoffman distinguish between situation awareness and sensemaking as follows:

...situation awareness is about the knowledge state that's achieved—either knowledge of current data elements, or inferences drawn from these data, or predictions that can be made using these inferences. In contrast, sensemaking is about the process of achieving these kinds of outcomes, the strategies, and the barriers encountered.^[34]

In brief, sensemaking is viewed more as "a motivated, continuous effort to understand connections (which can be among people, places, and events) in order to anticipate their trajectories and act effectively",^[35] rather than the state of knowledge underlying situation awareness. Endsley points out that as an effortful process, sensemaking is actually considering a subset of the processes used to maintain situation awareness.^[36] In the vast majority of the cases, SA is instantaneous and effortless, proceeding from pattern recognition of key factors in the environment—"The speed of operations in activities such as sports, driving, flying and air traffic control practically prohibits such conscious deliberation in the majority of cases, but rather reserves it for the exceptions." Endsley also points out that sensemaking is backward focused, forming reasons for past events, while situation awareness is typically forward looking, projecting what is likely to happen in order to inform effective decision processes.^[36]

Theoretical model

SA can be described in terms of a holistic framework of SA Systems, States, and Processes.^[2] SA descriptions usually focus on one of the three aspects, or on combinations. SA states can be described as:

Objects: Awareness of various objects in the world, and their current status. Objects and their status may be indicative of particular situations (that they are about to occur, that they are ongoing, etc.). Then they are often referred to as cues.

Frames: Awareness of what kind of situation is on-going, e.g. a runway incursion where an aircraft is about to collide with some object on the runway.

Implications: Awareness of objects within frames, of what their current status means in a particular situation. E.g. the implications of the current speed of the aircraft, and the distance to an object on the runway, in a runway incursion situation. The implications refer to time and space, to an event horizon.

Event horizon: An awareness of plans and events in time and space. It includes an awareness of what has happened (useful for diagnosis, to achieve SA, to frame situations). It also includes prognosis, an awareness of what might happen next. That includes on the one hand an awareness both of what might occur based on diagnosis and the current situation, and on the other hand on an awareness of current plans and intentions.

All four aspects may drive SA processes. Being aware of the status of particular objects (cues), one might infer that particular situations are on-going, and frame the objects accordingly. The cues then drive re-framing of situations. Having a particular frame, or pre-conception of a situation, this may drive the perception of objects. E.g. having noticed that a landing is about to occur, an Air Traffic Controller will usually look for specific objects in the environment and update the awareness of their status. Further, having realized the implications of objects of their status, this drives the process of what to attend to next. E.g. knowing that a vehicle is approaching a runway where a landing is about to take place, an Air Traffic Controller may monitor its progress. Event horizon awareness may also guide SA, e.g. if one plans to stop the car at a gas station, one may look for gas station signs.

Further, to describe SA in e.g. teams, the distribution of SA must be considered, e.g. in terms of:

Shared SA: What SA different agents have in common

Task SA: What SA different agents have, that they need to perform their tasks

Transactive SA: Exchange of SA between system parts

Buffering SA: Awareness of different accounts (e.g., different frames) of situations, in various parts of the system.

The SA states framework above extends an older (but simpler), theoretical framework of SA, provided by Dr. Mica Endsley (1995b), which has historically been widely used. Endsley's model describes SA states, and illustrates three stages or steps of SA formation: perception, comprehension, and projection.

Perception (Level 1 SA): 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 (objects, events, people, systems, environmental factors) and their current states (locations, conditions, modes, actions).

Comprehension (Level 2 SA): 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 (Level 3 SA): 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 (Levels 1 and 2 SA), and then extrapolating this information forward in time to determine how it will affect future states of the operational environment.

Endsley's model of SA also illustrates several variables that can influence the development and maintenance of SA, including individual, task, and environmental factors. For example, individuals vary in their ability to acquire SA; thus, simply providing the same system and training will not ensure similar SA across different individuals. Endsley's model shows how SA "provides the primary basis for subsequent decision making and performance in the operation of complex, dynamic systems" (Endsley, 1995a, p. 65). Although alone it cannot guarantee successful decision making, SA does support the necessary input processes (e.g., cue recognition, situation assessment, prediction) upon which good decisions are based (Artman, 2000).

Endlsey's model of SA. This is a synthesis of versions she has given in several sources, notably Endsley (1995a) and Endsley et al (2000). Drawn by Dr. Peter Lankton, May 2007.

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.

In summary, the model consists of several key factors:

• 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 (fed by the current model of the situation and by long-term memory stores) 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 (relevant to goals) 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.

For a more complete description of the model, see Endsley (1995b) and Endsley (2004). See also Endsley (2000) for a review of other models of SA.

Criticism of model

Any model of situation awareness depends on cognitive and shared cognitive processes, and yet '...models of SA refer to cognitive processes in general terms, but do not specify exactly what processes are involved and to what extent.' (Banbury & Tremblay, 2004, p. xiii). This criticism is an example of the difficulty that cognitive science has in addressing a concept such as SA, which through its definition and assumptions appears to stand robustly, however when the theorized processes are exposed at the cognitive level of analysis assumptions must be radically reviewed. Researchers have regularly raised these concerns - notably in Flach (1995) and more recently in Banbury & Tremblay (2004). To date the most widely cited model of SA is lacking in support from cognitive science, one notable observation that still stands is that:

'The test of Situation Awareness as a construct will be in its ability to be operationalized in terms of objective, clearly specified independent (stimulus manipulation) and dependent (response difference) variables ... Otherwise, SA will be yet another buzzword to cloak scientists' ignorance.' (Flach, J., 1995, p. 155)

Another criticism of the model comes from a study done in 2015 which looked at situational awareness in tasks where relevant knowledge about the task could be found through other mediums, other than directly asking the collaborator. It was found that in these types of tasks, verbal communication lengthens the time it takes to complete a task when compared to people completing a task individually. ^[37]

In team operations

In many systems and organizations, people work not just as individuals, but as members of a team. Thus, it is necessary to consider the SA of not just individual team members, but also the SA of the team as a whole. To begin to understand what is needed for SA within teams, it is first necessary to clearly define what constitutes a team. A team is not just any group of individuals; rather teams have a few defining characteristics. As defined by Salas et al. (1992), a team is:

"a distinguishable set of two or more people who interact dynamically, interdependently and adaptively toward a common and valued goal/objective/mission, who have each been assigned specific roles or functions to perform, and who have a limited life span of membership."

Team SA

Team SA is defined as "the degree to which every team member possesses the SA required for his or her responsibilities" (Endsley, 1995b, p. 39; see also Endsley, 1989). The success or failure of a team depends on the success or failure of each of its team members. If any one of the team members has poor SA, it can lead to a critical error in performance that can undermine the success of the entire team. By this definition, each team member needs to have a high level of SA on those factors that are relevant for his or her job. It is not sufficient for one member of the team to be aware of critical information if the team member who needs that information is not aware.

In a team, each member has a subgoal pertinent to his/her specific role that feeds into the overall team goal. Associated with each member's subgoal are a set of SA elements about which he/she is concerned. Team SA, therefore, can be represented as shown in Figure 2. As the members of a team are essentially interdependent in meeting the overall team goal, some overlap between each member's subgoal and their SA requirements will be present. It is this subset of information that constitutes much of team coordination. That coordination may occur as a verbal exchange, a duplication of displayed information, or by some other means.

Shared SA

Shared situation awareness can be defined as "the degree to which team members possess the same SA on shared SA requirements" (Endsley & Jones, 1997, p. 47; 2001, p. 48). As implied by this definition, there are information requirements that are relevant to multiple team members. A major part of teamwork involves the area where these SA requirements overlap—the shared SA requirements that exist as a function of the essential interdependency of the team members. In a poorly functioning team, two or more members may have different assessments on these shared SA requirements and thus behave in an uncoordinated or even counter-productive fashion. Yet in a smoothly functioning team, each team member shares a common understanding of what is happening on those SA elements that are common—shared SA. Thus, shared SA refers to the overlap between the SA requirements of the team members, as presented in Figure 3. As depicted by the clear areas of the figure, not all information needs to be shared. Clearly, each team member is aware of much that is not pertinent to the others on the team. Sharing every detail of each person's job would only create a great deal of "noise" to sort through to get needed information. It is only that information which is relevant to the SA requirements of each team member that is needed.

Team SA model

The situation awareness of the team as a whole, therefore, is dependent upon both (1) a high level of SA among individual team members for the aspects of the situation necessary for their job; and (2) a high level of shared SA between team members, providing an accurate common operating picture of those aspects of the situation common to the needs of each member (Endsley & Jones, 2001). Endsley and Jones (1997; 2001) describe a model of team situation awareness as a means of conceptualizing how teams develop high levels of shared SA across members. Each of these four factors—requirements, devices, mechanisms and processes—act to help build team and shared SA.

1. Team SA Requirements – the degree to which the team members know which information needs to be shared, including their higher level assessments and projections (which are usually not otherwise available to fellow team members), and information on team members' task status and current capabilities.

2. Team SA Devices – the devices available for sharing this information, which can include direct communication (both verbal and non-verbal), shared displays (e.g., visual or audio displays, or tactile devices), or a shared environment. As non-verbal communication, such as gestures and display of local artifacts, and a shared environment are usually not available in distributed teams, this places far more emphasis on verbal communication and communication technologies for creating shared information displays.

3. Team SA Mechanisms – the degree to which team members possess mechanisms, such as shared mental models, which support their ability to interpret information in the same way and make accurate projections regarding each other's actions. The possession of shared mental models can greatly facilitate communication and coordination in team settings.

4. Team SA Processes – the degree to which team members engage in effective processes for sharing SA information which may include a group norm of questioning assumptions, checking each other for conflicting information or perceptions, setting up coordination and prioritization of tasks, and establishing contingency planning among others.

In time critical decision-making processes

There are many industries where it is critical to make a correct decision within a strict time limit, based on the decision-maker’s knowledge of the current situation: for example air traffic controllers or surgeons. In these situations it is common that the key decision maker is supported by other team members or by complex monitoring systems feeding them information, which can involve multiple sources and formats of information. Even in these time-critical situations, the importance of having situation awareness (SA) is not constant: i.e. it is more critical to the outcome to have better SA for non-standard situations, such as points of high information traffic, extraneous activity and unforeseeable events. These ‘points of fracture’ are likely to cause additional workload on the individuals and therefore affect their SA and the time to make the decision. At the critical point the perceived situational awareness utilized to make the decision is directly affected by the cognitive workload to gain, comprehend and process the SA that is coming in to the operator, both general background SA and the SA specifically related to the decision. (Smith, K. T. 2013)^[38] In other words, if everything is going OK the level of SA you have is not as critical as it is when something unusual happens or something goes wrong.

Research into the decision making process is an increasing area of interest and the identification of this type of relationship has led to the development of at least one integrated conceptual framework (developed by K Tara Smith) that attempts to accommodate all of the impactors on the decision-making process, defining how they impact on the individual’s ability to acquire their SA. This involves aligning the terms and concepts used by different research areas, so that the causal relationships can be identified and defined.

This approach of integrating situation awareness, workload, signal processing theory, decision theory, etc. tends to subtly change the questions that are asked during the analysis process from quantifying and qualifying the SA to measures of the probabilistic aspects of a decision, such as the number of interrelationships, the certainty and time-lag of the information arriving, risk to desired outcome or effect, etc., together with the processing aspects, to do with the number of signals, accuracy and completeness of the information and importance to the operational context. In other words, instead of asking does a modification to the system provide more SA, we are asking does this modification to the system provide more SA in a form that can be used at the time when it is needed?

Measurement

While the SA construct has been widely researched, the multivariate nature of SA poses a considerable challenge to its quantification and measurement (for a detailed discussion on SA measurement, see Endsley & Garland, 2000; Fracker, 1991a; 1991b). In general, techniques vary in terms of direct measurement of SA (e.g., objective real-time probes or subjective questionnaires assessing perceived SA) or methods that infer SA based on operator behavior or performance. Direct measures are typically considered to be "product-oriented" in that these techniques assess an SA outcome; inferred measures are considered to be "process-oriented," focusing on the underlying processes or mechanisms required to achieve SA (Graham & Matthews, 2000). These SA measurement approaches are further described next.

Objective measures

Objective measures directly assess SA by comparing an individual's perceptions of the situation or environment to some "ground truth" reality. Specifically, objective measures collect data from the individual on his or her perceptions of the situation and compare them to what is actually happening to score the accuracy of their SA at a given moment in time. Thus, this type of assessment provides a direct measure of SA and does not require operators or observers to make judgments about situational knowledge on the basis of incomplete information. Objective measures can be gathered in one of three ways: real-time as the task is completed (e.g., "real-time probes" presented as open questions embedded as verbal communications during the task – Jones & Endsley, 2000), during an interruption in task performance (e.g., Situation Awareness Global Assessment Technique (SAGAT) – Endsley, 1995a, or the WOMBAT Situational Awareness and Stress Tolerance Test mostly used in aviation since the late 1980s and often called HUPEX in Europe), or post-test following completion of the task.

Subjective measures

Subjective measures directly assess SA by asking individuals to rate their own or the observed SA of individuals on an anchored scale (e.g., Participant Situation Awareness Questionnaire (PSAQ) – Strater, Endsley, Pleban, & Matthews, 2001; the Situation Awareness Rating Technique (SART) – Taylor, 1989). Subjective measures of SA are attractive in that they are relatively straightforward and easy to administer. However, several limitations should be noted. Individuals making subjective assessments of their own SA are often unaware of information they do not know (the "unknown unknowns"). Subjective measures also tend to be global in nature, and, as such, do not fully exploit the multivariate nature of SA to provide the detailed diagnostics available with objective measures. Nevertheless, self-ratings may be useful in that they can provide an assessment of operators' degree of confidence in their SA and their own performance. Measuring how SA is perceived by the operator may provide information as important as the operator's actual SA, since errors in perceived SA quality (over-confidence or under-confidence in SA) may have just as harmful an effect on an individual's or team's decision-making as errors in their actual SA (Endsley, 1998).

Subjective estimates of an individual's SA may also be made by experienced observers (e.g., peers, commanders, or trained external experts). These observer ratings may be somewhat superior to self-ratings of SA because more information about the true state of the environment is usually available to the observer than to the operator, who may be focused on performing the task (i.e., trained observers may have more complete knowledge of the situation). However, observers have only limited knowledge about the operator's concept of the situation and cannot have complete insight into the mental state of the individual being evaluated. Thus, observers are forced to rely more on operators' observable actions and verbalizations in order to infer their level of SA. In this case, such actions and verbalizations are best assessed using performance and behavioral measures of SA, as described next.

Performance and behavioral measures

Performance measures "infer" SA from the end result (i.e., task performance outcomes), based on the assumption that better performance indicates better SA. Common performance metrics include quantity of output or productivity level, time to perform the task or respond to an event, and the accuracy of the response or, conversely, the number of errors committed. The main advantage of performance measures is that these can be collected objectively and without disrupting task performance. However, although evidence exists to suggest a positive relation between SA and performance, this connection is probabilistic and not always direct and unequivocal (Endsley, 1995b). In other words, good SA does not always lead to good performance and poor SA does not always lead to poor performance (Endsley, 1990). Thus, performance measures should be used in conjunction with others measures of SA that directly assess this construct.

Behavioral measures also "infer" SA from the actions that individuals choose to take, based on the assumption that good actions will follow from good SA and vice versa. Behavioral measures rely primarily on observer ratings, and are, thus, somewhat subjective in nature. To address this limitation, observers can be asked to evaluate the degree to which individuals are carrying out actions and exhibiting behaviors that would be expected to promote the achievement of higher levels of SA (see, for example, the Situation Awareness Behaviorally Anchored Rating Scale (SABARS) – Matthews, Pleban, Endsley, & Strater, 2000; Strater et al., 2001). This approach removes some of the subjectivity associated with making judgments about an individual's internal state of knowledge by allowing them to make judgments about SA indicators that are more readily observable.

Process indices

Process indices examine how individuals process information in their environment, such as by analyzing communication patterns between team members or using eye tracking devices. Team communication (particularly verbal communication) supports the knowledge building and information processing that leads to SA construction (Endsley & Jones, 1997). Thus, since SA may be distributed via communication, computational linguistics and machine learning techniques can be combined with natural language analytical techniques (e.g., Latent Semantic Analysis) to create models that draw on the verbal expressions of the team to predict SA and task performance (Bolstad, Cuevas, Gonzalez, & Schneider, 2005; Bolstad, Foltz, Franzke, Cuevas, Rosenstein, & Costello, 2007). Although evidence exists to support the utility of communication analysis for predicting team SA (Foltz, Bolstad, Cuevas, Franzke, Rosenstein, & Costello, in press), time constraints and technological limitations (e.g., cost and availability of speech recording systems and speech-to-text translation software) may make this approach less practical and viable in time-pressured, fast paced operations.

Psycho-physiological measures also serve as process indices of operator SA by providing an assessment of the relationship between human performance and a corrected change in the operator's physiology (e.g., French, Clark, Pomeroy, Seymour, & Clarke, 2007). In other words, cognitive activity is associated with changes in the operator's physiological states. For example, the operator's overall functional state (as assessed using psycho-physiological measures, such as electroencephalographic (EEG) data, eyeblinks, and cardiac activity) may provide an indication as to whether the operator is sleep fatigued at one end of the continuum, or mentally overloaded at the other end (Wilson, 2000). Other psycho-physiological measures, such as event related potentials (ERP), event related desynchronization (ERD), transient heart rate (HR), and electrodermal activity (EDA), may be useful for evaluating an operator's perception of critical environmental cues, that is, to determine if the operator has detected and perceived a task-relevant stimulus (Wilson, 2000). In addition, it is also possible to use psycho-physiological measures to monitor operators' environmental expectancies, that is, their physiological responses to upcoming events, as a measure of their current level of SA (Wilson, 2000).

Multi-faceted approach to measurement

The multivariate nature of SA significantly complicates its quantification and measurement, as it is conceivable that a metric may only tap into one aspect of the operator's SA. Further, studies have shown that different types of SA measures do not always correlate strongly with each other (cf. Durso, Truitt, Hackworth, Crutchfield, Nikolic, Moertl, Ohrt, & Manning, 1995; Endsley, Selcon, Hardiman, & Croft, 1998; Vidulich, 2000). Accordingly, rather than rely on a single approach or metric, valid and reliable measurement of SA should utilize a battery of distinct yet related measures that complement each other (e.g., Harwood, Barnett, & Wickens, 1988). Such a multi-faced approach to SA measurement capitalizes on the strengths of each measure while minimizing the limitations inherent in each.

Training

Following Endsley's paradigm and with Cognitive Resource Management model^[39] with neurofeedback techniques, Spanish Pedagogist María Gabriela López García (2010) implemented and developed a new SA Training pattern.^[40] The first organization to implement this new pattern design by López García is the SPAF (Spanish Air Force). She has trained EF-18 fighter pilots and Cannadair firefighters.^[41]

This situation awareness training aims to avoid losing SA and provide pilots cognitive resources to always operating below the maximum workload that can withstand. This provides not only a lower probability of incidents and accidents by Human Factors, but the hours of operation are at their optimum efficiency, extending the operating life of systems and operators.^[42]

On-the-job examples

Emergency medical call-outs

In First Aid medical training provided by the American Red Cross, the need to be aware of the situation within the area of influence as one approaches an individual requiring medical assistance is the first aspect for responders to consider^[43] Examining the area and being aware of potential hazards, including the hazards which may have caused the injuries being treated, is an effort to ensure that responders do not themselves get injured and require treatment as well.

Situation awareness for first responders in medical situations also includes evaluating and understanding what happened^[44] to avoid injury of responders and also to provide information to other rescue agencies which may need to know what the situation is via radio prior to their arrival on the scene.

In a medical context, situation awareness is applied to avoid further injury to already-injured individuals, to avoid injury to medical responders, and to inform other potential responders of hazardous conditions prior to their arrival.

Search and rescue

Within the search and rescue context, situational awareness is applied primarily to avoid injury to search crews however being aware of the environment, the lay of the land, and the many other factors of influence within one's surroundings assists in the location of injured or missing individuals^[45]

Forestry crosscut saw / chainsaw

In the United States Forest Service the use of chainsaws and crosscut saws requires training and certification.^[46] A great deal of that training describes situational awareness as an approach toward environmental awareness but also self-awareness^[47] which includes being aware of one's own emotional attitude, tiredness, and even caloric intake.

Situational awareness in the forest context also includes evaluating the environment and the potential safety hazards within a saw crew's area of influence. As a sawyer approaches a task, the ground, wind, cloud cover, hillsides, and many other factors are examined and are considered proactively as part of trained sawyers' ingrained training.

Dead or diseased trees within the reach of saw team crews are evaluated, the strength and direction of the wind is evaluated. The lay of tree sections to be bucked or the lean of a tree to be felled is evaluated within the context of being aware of where the tree will fall or move to when cut, where the other members of the saw team are located, how they are moving, whether hikers are within the area of influence, whether hikers are moving or are stationary.

Law enforcement

Law enforcement training includes being situationally aware of what is going on around the police officer before, during, and after interactions with the general public^[48] while also being fully aware of what is happening around the officer in areas not currently the focus of an officer's immediate task.

In the law enforcement context, situation awareness involves keeping eyes and ears open and evaluating what is happening on the way to a specific task, remaining fully aware of one's surroundings during the commission of a task, and retaining one's awareness when exiting a specific task. Situational awareness in a law enforcement setting seeks to ensure that a police officer does not become focused and engrossed on a specific task or problem to the exclusion of being aware of approaching potential hazards or to the exclusion of being aware of other tasks of higher priority. Situational awareness is a 24/7^[49] process and policy laid down in Officer training.^[50]

Cybersecurity threat operations

In cybersecurity, consider situational awareness, for threat operations, is being able to perceive threat activity and vulnerability in context so that the following can be actively defended: data, information, knowledge, and wisdom from compromise. Situational awareness is achieved by developing and using solutions that often consume data and information from many different sources. Technology and algorithms are then used to apply knowledge and wisdom in order to discern patterns of behavior that point to possible, probable, and real threats.

Situational awareness for Cybersecurity Threat Operations teams appears in the form of a condensed, enriched, often graphical, prioritized, and easily searchable view of systems that are inside or related to security areas of responsibility (such as corporate networks or those used for national security interests). Different studies have analysed the perception of security and privacy in the context of eHealth^[51] , network security^[52] , or using collaborative approaches to improve the awareness of users^[53] .

See also

• Aviation safety
• Brownout (aeronautics)
• Decision-making
• Information integration
• Korean Air Lines Flight 007
• Self-awareness
• Situated cognition
• Spatial disorientation
• Single-Pilot Resource Management

References

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2. Lundberg, 2015
3. Nullmeyer, Stella, Montijo, & Harden 2005
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24. Sanjay Kumar Boddhu, Matt McCartney, Oliver Ceccopieri, et al., "A collaborative smartphone sensing platform for detecting and tracking hostile drones", Proceedings of SPIE Vol. 8742, 874211 (2013)
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46. US Forest Service, Chain Saw and Crosscut Saw Training Course – Accessed 01/Aug/13
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48. Police Chief, Improving Situational Awareness – Accessed 01/Aug/13
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50. Personal Safety, What Is Situational Awareness? – Accessed 01/Aug/13
51. Bellekens, Xavier; Hamilton, Andrew; Seeam, Preetila; Nieradzinska, Kamila; Franssen, Quentin; Seeam, Amar (2016). "Pervasive eHealth services a security and privacy risk awareness survey": 1–4. doi:10.1109/CyberSA.2016.7503293.
52. Best, Daniel M.; Bohn, Shawn; Love, Douglas; Wynne, Adam; Pike, William A. (2010). "Real-time visualization of network behaviors for situational awareness": 79–90. doi:10.1145/1850795.1850805.
53. Mathews, Mary; Halvorsen, Paul; Joshi, Anupam; Finin, Tim (2012). "A Collaborative Approach to Situational Awareness for CyberSecurity". doi:10.4108/icst.collaboratecom.2012.250794.

Notes

• FDSE's COP Page
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