The effect of an ergonomic intervention on musculoskeletal, psychosocial and visual strain of VDT entry work: organization and methodology of the international study.

This special issue of the International Journal of Occupational Safety and Ergonomics (JOSE) reports the results from an extensive multinational and multidisciplinary collaborative investigation of the impacts on visual display terminal (VDT) work of musculoskeletal, visual, ergonomic, and psychosocial factors. For brevity, this effort has been referred to as the MEPS project (musculoskeletal--eyestrain--psychosocial--stress). This paper lays out the basic methodological structure of the study. The study was conducted in 4 countries utilizing VDT data entry workers as the primary subject population. A battery of objective and subject assessment measures, including muscle load, visual function, physical and visual strain, postural, ergonomic and psychosocial factors, were assessed at 3 different points in time. A pre-test was given prior to an ergonomic intervention. Two post-tests were given 1 month and 1 year after the ergonomic intervention.     

The effect of an ergonomic intervention on musculoskeletal, psychosocial and visual strain of VDT data entry work: the Norwegian part of the international study.

The Norwegian MEPS (musculoskeletal--visual--psychosocial--stress) study included 3 groups: data entry, data dialogue (female) and data dialogue (male). Before intervention, the data entry group reported significantly more symptoms and signs of musculoskeletal illness and had longer periods in front of the video display terminal (VDT) without a break. The ergonomic intervention consisted mainly of ergonomic information and training. After intervention, the data dialogue female group reported a significant reduction in shoulder pain in parallel with a reduction in trapezius load. Increasing the understanding in how to adjust the work stand and chair may have been contributing factors to reducing the pain level. There was a significant reduction in eye problems in all groups; the greatest reduction in eye symptoms was seen in the groups who had new optometric corrections.     

The effect of an ergonomic intervention on musculoskeletal, psychosocial, and visual strain of VDT data entry work: the Polish part of the international study.

A group of routine data entry operators (female) was included in the Polish MEPS (musculoskeletal--eyestrain--psychosocial--stress) study. Before the intervention, ergonomic assessment revealed improper working conditions such as inadequate lighting, uncomfortable chairs, and lack of forearm and wrist support while medical examination revealed that trapezius muscle load along with upper arm, head and back angles were higher than advisable. Subjects complained about neck and shoulder pain, visual problems, and psychosocial conditions. The ergonomic intervention included installation of new luminaires and Venetian blinds, new chairs, repair of ventilators, and optometric corrections. The results after the intervention showed mainly improvement in chair comfort, lighting conditions, visual strain, and sitting posture. However, financial limitations did not allow satisfactory completion of the intervention leading to a mixed interpretation of the results.     

The effect of an ergonomic intervention on musculoskeletal, psychosocial, and visual strain of VDT data entry work: the United States part of the international study.

The United States MEPS (musculoskeletal--eyestrain--psychosocial--stress) study consisted of 1 group of 28 female data entry operators. The intervention was in 3 parts: workstation redesign (including advanced ergonomic chairs, motorized adjustable workstations, advanced adjustable keyboards, adjustable copyholders, adjustable footrests, monitor support surfaces) and ergonomic training/coaching and corrective lenses. After the intervention, statistically significant reductions in physical signs (trigger points, neck and shoulder mobility), subjective reports of intensity and frequency of musculoskeletal pain, and subjective reports of visual problems were observed. Static load during the work sample, as assessed by experts, improved after the intervention as did measured postural angles of head and trunk and subjective assessment of users of ergonomic characteristics of the workplaces. For all of these measures, improvements observed 1 month after intervention were also observed in the 1-year follow-up. Trapezius load, as assessed by electromyography (EMG), decreased after intervention, but then increased in the follow-up. The increase was interpreted as a calibration problem.     

Strategies of international cooperation in an international project: advantages and pitfalls.

The MEPS (musculoskeletal--eyestrain--psychosocial--stress) study involved an extensive degree of multidisciplinary and multicultural cooperation. The objective was to examine the effects of multiple ergonomic interventions on visual, musculoskeletal, postural, and psychosocial outcomes amongst operators of visual display terminals (VDTs). The inherent complexity of a comprehensive ergonomic investigation requires participation of researchers from a variety of disciplines, as well as comparisons among populations with different geographical and cultural backgrounds. The design and execution of the resulting research protocol presents a number of challenges. This paper discusses the advantages and pitfalls associated with multidisciplinary multinational cooperation. Advantages include the necessity for development of a common language and perspective providing a basis for future collaboration. Pitfalls include logistic and coordination difficulties associated with conducting standardized procedures in different locations, as well as the inherent potential for professional conflict. It is argued that such pitfalls ought to be understood and integrated into the project planning process.     

The effect of artificial smoke compound on physiological responses,cognitive functions and work performance during firefighting activities in a smoke-diving room: an intervention study

This study investigated the combined effect of firefighting operations and exposure to smoke on physiological responses, cognitive functions and physical performance among firefighters. Each firefighter was engaged in two experimental conditions: (a) without artificial smoke, control (NS); (b) with artificial smoke (WS). The results of data analysis revealed that heart rate and body temperature increased significantly after the firefighting activities in the two conditions relative to baseline. In addition, reaction time (RT) and correct response (CR) decreased after the activity relative to baseline and there was a significant difference in RT and CR between the NS and WS conditions. There was also a significant difference in performance time between the NS and WS conditions. These findings demonstrated that a smoke compound has an insignificant effect on physiological responses during firefighting activity. On the contrary, the smoke compound has a detrimental influence on cognitive and physical performance.