broad categories and the specific categories of occupational stress mentioned in the following paragraph fall under different psychological theories of worker stress, which include demand-control-support model, the effort-reward imbalance model, the person-environment fit model, job characteristics model, the diathesis stress model, and the job-demands resources model. (All these models are expanded upon earlier in this Wikipedia page). The causes of occupational stress can be placed into a broad category of what the main occupational stressor is and a more specific category of what causes occupational stress. The broad category of occupational stressors include some of the following: bad management practices, the job content and its demands, a lack of support or autonomy and much more. The more specific causes of occupational stress includes some of the following: working long hours, having insufficient skills for the job, discrimination and harassment and much more. General working conditions Although the importance of individual differences cannot be ignored, scientific evidence suggests that certain working conditions are stressful to most people. Such evidence argues for a greater emphasis on working conditions as the key source of job stress, and for job redesign as a primary prevention strategy. In the ten years leading up to 2015, workers in the EU and affiliated countries have seen improvement in noise exposure but worsening in exposure to chemicals. Approximately, one-third of EU workers experience tight deadlines and must work quickly. Those in the health sector are exposed to the highest levels of work intensity. In order to meet job demands, a little more than 20% of EU workers must work during their free time. Approximately one-third of EU workers in lower-level jobs have some decision latitude. By contrast, about 80% of managers have significant levels of latitude. General working conditions that induce occupational stress may also be aspects of the physical environment of one's job. For example, the noise level, lighting, and temperature are all components of one's working environment. If these factors are not adequate for a successful working environment, one can experience changes in mood and arousal, which in turn creates more difficulty to successfully do the job right. Workload In an occupational setting, dealing with workload can be stressful and serve as a stressor for employees. There are three aspects of workload that can be stressful. Quantitative workload or overload: Having more work to do than can be accomplished comfortably. Qualitative workload: Having work that is