Abstract

The aim of the present study was to characterise the working conditions of the workers of video display terminals (VDT) and to reduce health risks by using an ergonomic design of workplaces and counselling of workers.
Methods. In the course of the present study the ergonomic inspection of working rooms and workplaces was carried out, and the questioning of workers, by using special forms, and the interviewing of representatives of employers and employees were performed. Risk  assessment was performed on the basis of British Standard 8800. The employees passed health examination in accordance with legal acts valid in Estonia. Within health examination more attention was paid to the detection of symptoms of the static overload of muscles caused by computer work. For objective estimation of overload symptoms, the function of the muscles and joints causing subjective complaints was determined, and the levels of muscle tension and pain sensitivity were estimated.
Results. Risk assessment was carried out in 810 workplaces of 15 enterprises and the health examination of 826 workers of VDTs was simultaneously performed. Altogether 826 persons participated in the study, 48.7% of them male and 51.3% female workers. In the course of the ergonomic inspection of workplaces, a number of shortcomings were found, among which some of them can be easily eliminated without additional investments.
According to British Standard 8800, the risk level in 25% of the VDT workplaces was estimated at least as satisfactory, which means that the risk factor is appreciable  and may cause health disorders. Nearly 15% of the VDT workers were diagnosed with work-related overload symptoms in the muscles of the shoulder region and the upper limbs or/and the back.
Conclusions. 1. More than half of the investigated VDT workers use video displays during more than 75% of their working time. The compulsory posture resulting from this working process poses potential health risk. 2. The risk assessment of VDT workplaces requires detailed and competent ergonomic inspection and design, as well as counselling of workers. 3. Even today when the length of service of VDT workers is considerably short, overload symptoms in the muscles of the shoulder region and the upper limbs and/or back are diagnosed in nearly 15% of the workers. 4. As working with video display terminals is widespread and causes muscular damage more often, it becomes more relevant to improve the techniques of risk assessment and make use of such methods which objectively enable to estimate the condition of the muscular system of VDT workers.