Stress is an inevitable and essential part of life and follows a pervasive phenomenon, and it spreads widely throughout the life of employees. Occupational stress determines the condition of psychological stress associated with employees' work. It usually originates from pressures, which do not align with employees' skills, knowledge, or expectations. Job stress might increase when workloads are often excessive or too low. Workers often experience stress at the workplace, which keeps them motivated for their survival and growth. It affects employees regardless of their age, gender, race, economic status, or education level. Although it is a natural and necessary aspect of life, if the stress is severe, persistent, or repetitive, the individual maybe is unable to cope with it effectively. In the event where support resources are scarce, and casualties are increasingly more, stress refers to a negative phenomenon or catastrophe, which may cause physical and mental disorders [1]. Occupational stress has become a common and neglected issue in the workplace, creating negative consequences, and an overall high cost for organizations. As a result, the United Nations has called it a twentieth-century disease. In recent years, the World Health Organization (WHO) has declared it a widespread problem worldwide [2]. Numerous studies have shown the role of occupational stress in connection with disease symptoms, high labor displacement, and individuals' early retirement [3, 4]. The Health and Safety Executive has predicted over 13.5 million working days and more than £4 billion losses annually due to the damages from occupational stresses during 2007-2009 [5, 6].
In this regard, several organizations have implemented measures to protect the health and well-being of their employees. One of these organizations is the Disaster and Emergency Medical Management Center, which is responsible for providing clinical care to patients in a pre-hospital medical emergency and transferring to medical centers if necessary [7, 8]. Emergency Medical Services (EMS) staff are typically the first health professionals to participate in intensive care, providing care to injured and critically ill patients, suspended between life and death. As a result, these people often face specific conditions in which they experience professional stress [9, 10].
Health center is one of the main pillars of emergency health care units in all countries around the globe. According to the world's modern scientific standards, this system's most fundamental goal is to provide satisfactory services in the shortest possible time to the patients. [11]. Emergency medical services units differ from the other sections through a variety of ways, such as stressful environments, high pressure, the sensitivity of seconds, extraordinary stress on timely diagnosis, expectations and intimidation of near and dear ones, and the importance of protecting patients' lives [12]. Therefore, this is the highly stressed area of the medical services unit. The emergency medical services system is a part of a chain system responsible for patients' care from the severe critical time to their rehabilitation and discharge [13]. The personnel employed in this section are as the first individuals to respond to patients in emergency medical situations and the first sight of the critical moment [14]. This section provides the conditions in creating stress for the personnel employed in this sector due to time constraints in performing affairs, the critical status of the patient, expectations of companions, the openness of the environment, fear of inadequacy in rescuing a dying patient, decision-making power in urgent situations and factors related to workforce [15, 16].
The prolonged exposure of emergency medical personnel to unpredictable stress settings leads to some scholars to classify them as people at high risk of exposure to PTSD [17, 18]. Besides, if stress is not adequately addressed and properly managed in the right way, it can lead to many physical and psychological symptoms of EMS staff [19]. Some of such symptoms refer to anxiety[20, 21], depression [22], , sleep disorders, fatigue and unsafe behavior[23], gastrointestinal symptoms, backache [24], diminished occupational satisfaction [25], occupational burnout[26], emotional disturbance, and depersonalization[27, 28].
Increasing working hours causes an increase in conflict in occupational and family tasks, leading to occupational stress [29]. The rotating nature of work shifts of emergency medical technicians gives little opportunity to adapt to sleep patterns that can disrupt mental health [30]. Consequently, the effects of day and night shifts can be fatigue, sleep disorder, gastrointestinal disorders, and poor performance [31]. In domestic studies, Sharifi et al., in their research in Kerman, concluded that about half of emergency medical personnel experienced moderate occupational stress. There was a significant relationship between occupational stress with educational level and employment status, while age and marital status didn't have any relationship with stress [32]. The results of Dadashzadeh et al. study in urban and road bases and pre-hospital emergency medical services in East Azarbaijan province showed that the most critical factor of stress load is occupational, environmental factors, and factors related to a patient. There was also a significant relationship between the amount of stress load with the number of missions, educational degree, and type of base and employment status [33]. Seyed Javadi et al., in a study conducted on employees in 115 provinces of Ardabil, stated a significant correlation between age and occupational stress. Still, there was no relationship between stress and marital status, educational level, type of workplace base, and working hours per week [34].
In foreign studies, the results of a study in the UK showed that emergency medical technicians had the highest rank in terms of physical stress, the second rank in terms of dissatisfaction, and the fourth rank in terms of mental health compared to the other 25 jobs [35]. The results of a study conducted in Turkey demonstrated that all the stressful and unfavorable conditions in the pre-hospital emergency medical services lead to the personnel's physical and psychological fatigue and eventually lead to burnout development [36]. Leszczynski et al. emphasized that physicians and nurses in the emergency medical services department suffered more burnout than emergency medical personnel did. They stated that emergency medical service personnel experienced the least amount of burnout compared to their colleagues [37]. Besides, the problems discussed above, emergency medical personnel employed by the Iranian Government's health-care system are involved in addressing other challenges, such as staff shortages, inadequate equipment, inadequate training of the necessary standards, interaction with people, skills training issues, anxiety and various forms of emotional distress [9, 38].
Despite all the studies conducted, reviewing different backgrounds indicates that no research was conducted in Kermanshah University of Medical Sciences to assess the occupational stress of the personnel employed in 115 of the Kermanshah provinces. Thus, keeping in view the stature of job, occupational stress is prominent in emergency medical workers, which is considered a key element in health systems. It provides the optimal provision of health care and clinical services for affected at a critical moment. This study focused on investigating the personnel's occupational stress status of the disaster and emergency medical management center 115, and the role of demographic variables play in 2019. This issue enables planning and comparison with other areas of the country while identifying specific cases supporting counseling and treatment.