OCCUPATIONAL STRESS AND STRESS PREVENTIONIN AIR TRAFFIC CONTROL
...g emotional reactions, such as in the case of air accidents with loss of life or serious injury, near collisions or loss of control due to overload. The psychic (anger, guilt, grief, anxiety) and physical reactions (hypertension, headache, sweating, heartburn, insomnia), not only hamper work performance but can also give rise to long-term post-traumatic disorders. 9. The consequences on an ATCO’s performance and well being may differ widely among individuals in relation to many factors dealing with age, life styles, life events, work experience, personality traits behavioral characteristics, attitudes, motivation, and physical and mental health. It is often very difficult to evaluate and compare the effective stress and strain in different groups and individuals. EFFECT OF STRESS 10. Main consequences of stress for air traffic controllers. The effect of stress can be short-term and/or long-term on health. These are further more influenced by (a) Personality traits, aptitude and skill (b) Motivation (c) Experience and Operating behaviour (d) Coping strategies and Social support 11. Short Term Effects. With regard to the short-term effects, an ATCO’s responses can be identified in terms of changes in hormonal secretion, heart rate, blood pressure, muscular activity, cerebral waves, work performance (errors) and behaviour (sleeping, smoking, eating and drinking habits). These can indicate a normal, physiological adaptation of the individual to external stimulation, as well as an excessive strain due to an imbalance between demands and resources. These responses are in some way related to the workload, which can be evaluated in terms of the number of aircraft under control or expected to come under control, peak traffic counts, duration and type of communications, tight work schedules, and number and complexity of problems to be solved. On the other hand, they appear to be greatly influenced by subjective factors, such as personality traits (anxiety, introversion), aptitude, skill, ability, motivation, experience and operating behaviour. 12. Long Term Effect In the long term, this demanding occupational activity may be a risk factor for stress-related symptoms, such as headaches, chronic fatigue, heartburn, indigestion and chest pain, as well as for serious illnesses, such as hypertension, coronary heart disease, diabetes, peptic ulcers and psychoneurotic disorders. It is quite easy to foresee the high costs from both the existential and the economic point of view that these negative consequences of stress can have, not only for the single person, but also for the organisation and the society. Prevention and control of stress should become a compulsory target for ATCOs, in order to improve the efficiency and reliability of the Air Traffic services, as well as for IAF as a whole, in order to guarantee the highest levels of safety and comfort for all. HOW TO PREVENT STRESS AT WORK 13. An effective strategy shall address both the causes and the consequences of stress, thus acting upon all factors involved concerning work, personal resources and social conditions of the controllers. With respect to the peculiar aspects of an ATCO’s job, the possibilities at the different levels should be examined 14. Social support Social support is a crucial point in stress management. One of the aspects is the recognition at a social level of the importance of ATCOs’ activities and, consequently, its appreciation by the people. ATCOs’ complain that the average personnel do not fully understand the complexity and importance of their job, which is often considered “second class”. The controllers’ descriptions of their own profession are very emphatic: ie “ultra specialized, honourable, indispensable, irreplaceable, unique” ... They go at length to prove that this profession is unlike the others, and that it is one to be carried out with pride. This internal acknowledgement makes up for a lack of external image: the profession is little known and is even often blamed for causing traffic delays and accidents. This is probably due scarcity of information and understanding, therefore, the ATC setup should put in effort to give people adequate information about the ATC activities and complexity of such activities, so that people can better appreciate the ATCOs’ job and their role in IAF. 15. Improving of ATS systems. The passage from the old procedural methods to modern assistance, under total radar coverage of air space, is the main factor which enables a “jump in quality”, not only in terms of work efficiency, but also in terms of reduction in stress levels, by reducing memory and communicative loads as well as uncertainty and unpredictability of the situations that are, in most cases, the main sources of stress. These improvements may also subsequently reduce the possibility or the seriousness of many unforeseen situations, by allowing for more reliable information and more time for solving problems and making decisions, while eliminating many stressful and risky traffic peaks. The goal of progressive automation should be to maximize system safety and efficiency by reducing human workload, stress and error. 16. Workload and Duty Periods The mental effort, required to maintain the highest level of attention and vigilance, as well as to safely and effectively face the task in terms of cognitive and memory load, can vary widely in relation to air traffic density and connected problems. Therefore, to guarantee the best level of performance efficiency avoiding excessive mental stress and fatigue, particular attention has to be paid to arranging duty periods. In relation to the peculiarity of the job and the characteristics of the demands, it is worth stressing that one of the most important aspects in this domain is flexibility, which should be used in scheduling duty periods and arranging working teams according to the air traffic density. The regulation of working hours should be aimed at ensuring, as far as reasonably possible, that controllers’ fatigue does not endanger aircraft, and thereby to assist controllers in providing a service safely and effectively. 17. Arrangement of shift. Shift work, in particular afternoon/night work, is a further stress factor for the ATCOs due to its negative effects on various aspects of their lives. The forward rotation (e.g. morning-afternoon-night) should be preferred to the backward one (e.g. afternoon-morning-night) as it allows a longer period of rest between shifts. Adjusting the length of shifts according to the physical and mental workload: day shifts should be shorter, whereas afternoon shifts could be longer if the workload is reduced and there are sleeping facilities with a possibility of a short sleep or a nap during the afternoon/night shift. This will have favorable effects on performance, physiological adjustment and tolerance of afternoon/night work. Include some free weekends as this allows a better organization of personal, family and social life. 18. Participation in Decision Making. Most of the controllers are satisfied with the intrinsic content of their work, they are rather dissatisfied with other aspects of the job, such as organizational structure, the value placed upon their efforts. Participation of the controllers in decision making appears to be necessary to increase perceived influence, motivation, job satisfaction and performance efficiency, as well as to decrease stress and relative negative consequences, not only for the individual, but also for the organization with respect to role conflicts and role ambiguity, exasperated criticisms, etc. The adaptation of the controllers to such changes will depends greatly on their involvement in the decision making process, particularly as it concerns utilization of skill and creativity in an apparently more active role, that otherwise can give rise to frustration and alienation. 19. Improving the work environment. Particular attention has to be given to ensuring that environmental conditions in the control positions are suitable and comfortable with respect to: (a) Lighting The ATCO's task is performed almost exclusively in front of a visual display unit, particular attention should be paid to providing lighting conditions that favour an optimal visual performance. In the radar op room, dim light is usually used to favour the visual contrast on the screen. Opting for modern screens that are brighter and in colour, allows an increase of the illumination levels in the control room, thus avoiding excessive and troublesome luminance contrasts between central and lateral visual fields, making the environment more stimulating, thus increasing vigilance and alertness. The diffuse lighting in the work environment should be without shadows and glare. Flickering of light should not take place as it is extremely annoying, causes visual discomfort and makes the reading of the different traces on the screen more difficult. Inside the towers, the opposite is the problem. It is necessary to avoid excessive illumination levels due to external bright light using both anti-reflection glass and curtains; it is also important to have the possibility of positioning and shielding the visual display units to avoid indirect glare due to bright reflections on the screen. (b) Noise. The noise levels recorded inside control rooms can have significant effects in terms of interference with speech communication and mental concentration. The main sources of noise are conversations, manual operations, telephones, loud speakers, protophones, etc. Therefore attention has to be paid to restrict background noise by arranging work sectors to have better sound protection by installing insulating headsets and sensitive microphones. 20. Microclimatic conditions A comfortable working temperature is another important factor supporting the maximum efficiency of performance. As the conditions of thermal discomfort results in loss of concentration and efficiency of mental tasks with a consequent increase of errors and irritability, microclimatic conditions must be maintained within the range of thermal comfort (20 - 24C and humidity 30 - 70 %). To ensure these conditions, it is necessary to install adequate air conditioning systems that must be maintained efficiently to guarantee a good indoor air quality. 21. Workstation design Particular attention has to be paid to the configuration of the workstation with respect to radar console layout, auxiliary displays, the design of the keyboard and other interfaces. Information and controls must be easy to understand and input devices that are easy to operate. Appropriate use of colors, symbols, line shaping, windows and figures facilitates and hastens data recognition and extraction. The interaction between the ATCO and a visual display terminal are mainly characterized in terms of data acquisition and interactive communication. The radar controller concentrates mainly on the radar screen and periodically glances at the side displays and keyboard. Data displays containing flight information should preferably be located beside the radar screen, whereas the auxiliary displays showing maps or other complementary information can be placed above. The radar screen should be placed in the centre of the visual field and should be adjustable in height, distance and angle to give the operator the possibility of arranging the best working position in order to avoid, on the one hand, prolonged contraction of the neck muscles and, on the other hand, an excessive effort of visual adjustment with consequent visual discomfort and fatigue. Therefore, it is recommended that the screen be placed within a viewing angle of 5° above and 30° below the horizontal plane of sight, and that the eye-sc...