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Individual symptoms

It is important to preface this section by emphasising that exposure to stressors does not necessarily produce negative effects, particularly for experienced personnel. There may be immediate positive effects, such as increased motivation and energy, faster reactions, clearer thinking and improved memory retrieval (Charlton, 1992; Orasanu and Baker, 1996). Referring back to Figure 7.1, it is only when the perceived level of challenge begins to exceed the individual’s judged ability to cope with the stressors that the symptoms of distress become predominant (Flin, 1996a), so only negative effects are discussed below.

Figure 7.4 depicts a comprehensive categorisation of acute stressors. These may not be applicable or of equal intensity for all high-demand situations. In addition, a wide range of effects of stress exist, causing a complex pattern of behavioural, emotional, somatic (physical) and cognitive, or thinking, reactions (see Tables 7.77.10). As with the discussion of indicators of chronic stress, the ‘BEST’ acronym has been used to categorise the acute stress indicators.

B: Behavioural indicators. The effects of acute stress on behaviour are generally the most readily observable. As Flin (1996a) pointed out for acute stress and discussed earlier for chronic stress, there is not a finite list of behavioural effects, but the defining feature is a change in the individual’s normal behaviour pattern. Again, the behaviour change can be subtle (although there may be clues that a key team member is not performing his or her job properly), then the better team members know each other, the more likely that any behaviour changes will be noticed. table 7.7 outlines a number of behavioural symptoms.

Table 7.7 Behavioural indicators of acute stress



  • • hyperactivity
  • • anger
  • • argumentativeness
  • • irritability
  • • jumpiness
  • • aggressiveness
  • • swearing
  • • emotional outbursts
  • • withdrawn (‘switch off’)
  • • detached
  • • apathetic
  • • disengaged from surrounding activities

E: Emotional indicators. As with the behavioural indicators, different emotional responses can occur as part of the acute stress response. Indicators can range from apprehension and anxiety, fear, to loss of emotional control, where the individual becomes aggressive or visibly distressed (e.g. crying; see Table 7.8).

Table 7.8 Emotional indicators of acute stress

• fear

• fear of failure

• anxiety

• vulnerability

• panic

• loss of control

S: Somatic (physical) indicators. this is a pronounced physiological adaptive response that prepares the individual to fight or flee when the brain perceives a threat in the immediate environment (for a list of symptoms see table 7.9). Апу situation perceived by an individual to be very demanding or challenging can produce these effects.

Table 7.9 Somatic indicators of acute stress

• energy surge

• muscle tension (trembling)

• increasing heart rate

• heightened sensitivity (e.g. to noise)

• sweating

• effects on digestion

• dry mouth

(butterflies in stomach)

T: Thinking (cognitive) indicators. Stress has a wide range of detrimental effects on thinking. Cognitive activities such as perception, memory, decision-making and task-planning have previously been found to be negatively affected by stress (Mumaw, 1994). Table 7.10 provides a description of some of the negative effects that stress can have on memory, concentration and decision-making. However, it is useful to note that some stress responses may produce some performance-enhancing effects. task-shedding may be an adaptive function if tasks are shed in an optimal sequence, with the least important tasks abandoned first. Also, when under stress, people prefer to use well-learned techniques to deal with situations, so can revert to familiar rules or recognition-primed decision-making (see Chapter 3). this is known as the availability bias (tversky and Kahneman, 1974). these techniques can be brought quickly into consciousness and require little cognitive effort. thus pilots are given extensive training to deal with situations such as an engine failing when the plane is taking off, as they have to take the correct sequence of actions very quickly with no time to consult a manual or deliberate on the appropriate response.

Table 7.10 Thinking (cognitive) indicators of acute stress



Impairment of memory

  • • prone to distraction
  • • confirmation bias (tend to ignore information that does not support following a particular chosen course of action or model)
  • • information overload
  • • task-shedding (the abandonment of certain tasks when stress or workload make it difficult to concentrate on all of the tasks simultaneously)

Reduced concentration

  • • difficulty prioritising
  • • preoccupation with trivia
  • • perceptual tunnelling (attention becomes narrowly focused on salient cues)

Difficulty in decision-making

  • • availability bias (resort to familiar routines and not consider plans that are not immediately available in memory)
  • • ‘stalling thinking’ - mind blank

Box 7.2 provides an example of how the effects of acute stress led to a failure in leadership during the Piper Alpha oil platform disaster.

Box 7.2 An example of the effects of acute stress: the Piper Alpha disaster

occidental’s Piper Alpha platform was situated in the North Sea 110 miles northeast of Aberdeen, Scotland. On 6 July 1988, there was an explosion on the production deck of the platform. The resulting fire spread rapidly and was followed by a series of smaller explosions. At about 22:20 there was a major explosion caused by the rupturing of a pipeline carrying gas from the nearby Texaco Tartan platform. Over the next three hours a high-pressure gas fire raged, punctuated by a series of explosions. Of the 226 men on board, only 67 survived.

‘The explosion on the Piper Alpha that led to the disaster was not devastating. We shall never know, but it probably killed only a small number of men. As the resulting fire spread, most of the Piper Alpha workforce made their way to the accommodation where they expected someone would be in charge and would lead them to safety. Apparently they were disappointed. It seemed the whole system of command had broken down’ (Sefton, 1992: p6).

Evidence from the Cullen (1990) report into the accident showed the inability of the offshore installation manager (OIM; the most senior member of staff on the installation)

  • - the man responsible for organising the response to the emergency on the Piper Alpha
  • - to ‘take critical decisions and lead those under his command in a time of extreme stress’ (para 20.59). It was clear that the OIM on Piper Alpha was suffering from many of the symptoms of acute stress outlined above.

‘The OIM had gone a matter of seconds when he came running back in what appeared... to be a state ofpanic... The OIM made no specific attempt to call in helicopters from the Tharos [a rescue vessel] or elsewhere, or to communicate with the vessels around the installation; or with the shore or other installations; or with personnel on Piper ’ (para 8.9).

‘The OIM did not give any other instruction or guidance. One survivor said that at one stage people were shouting at the OIM and asking what was going on and what procedure to follow. He did not know whether the OIM was in shock or not but he did not seem to be able to come up with an answer ’ (para 8.18).

Furthermore, the radio operator said that ‘he himself was also panicking and the message [that the platform was to be abandoned] was haphazard’ (para 8.9).

Team symptoms

As with individuals, stressors can also affect overall team performance. When under stress, team members are more likely to become focused on their own tasks,

resulting in a decline in team performance. When people are under high stress, there is a tendency to regress to more basic skills where the individual is comfortable operating rather than maintaining an overview (Charlton, 1992). Further, it may be that only one team member needs to be affected by stress for the team’s performance to be significantly degraded. Therefore, the symptoms of stress at the team level are failures in teamworking, communication and decision-making (see earlier chapters for a discussion).

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