Administrative rationality and coping strategies in shift work

Shift work (SW) can affect worker health and productivity. Working at night, workers often accumulate fatigue and are less productive. In Brazil, laws have been drafted aiming to reduce night work and rotating shift hours. In order to slash costs, companies have been looking for new arrangements to improve productivity under these conditions. The purpose of this study was to examine management changes and their outcomes in a large glass factory located in an industrial region of Brazil. The results show that the management, seeking equal productivity among shifts, focused its efforts mainly on distributing employee expertise. The arrangement resulted in 12 different groups that combine to serve three fixed shifts. A same shift can be served by more than one group, and the members of a same group share days off on different days. There was no statistically significant productivity difference among the three shifts. The on-site examination showed that part of the production was held by the workers and transferred to the next shift in order for them to be able to meet the management's performance rate requirements. The finding shows how a Brazilian cultural trait (resistance without conflict) is used to drive coping in SW.     

Proposal for an integrative methodology to development the ergonomic program

This paper collects the experience for both, academic and professional practice, and deal with the stages and level of involvement from different elements in the organization. The work is focused in some kind of concentric cycles, the very outside circle is formed by those that interact with ergonomic process in a year period, and the inner cycles are those that acts in a daily or weekly intervention. The success of the program still depending on the good will of the managers, but any action directed on benefit of the people at work, enable the moral as well as indicators for health and safety.     

Ergonomic factors and production target evaluation in eucalyptus timber harvesting operations in mountainous terrains

There are several forest operations involved in Eucalyptus timber harvesting. This study was carried out during brush-cutting; tree felling, bucking, delimbing, piling and manual extraction operations, with the following objectives: a) analyzing, ergonomically, two systems of brush-cutting: one manual and the other semi-mechanized, using two different machines; b) ergonomically evaluating three different brands of pruner machines used in delimbing felled trees. c) determining the feasible target of productivity as a function of ergonomic factors relevant to establish the time of resting pauses for workers in manual and semi-mechanized timber harvesting systems in mountainous terrain. Brush-cutting, either manual or semimechanized, is an activity carried out prior to timber harvesting. It is usually a hard work, with low productivity when compared with mechanized systems. Pruner machines have been used by forest companies, due to the great possibilities to improve productivity, quality and the health of workers. Ergonomics is a discipline that promotes the adequacy of work to the physical and mental characteristics of human beings, seeking to design production systems and products considering relevant aspects, including social, organizational and environmental factors. Companies should consider the ergonomic factor in the determination of daily worker production targets.     

Participatory ergonomics among female cashiers from a department store

The objective of this paper was to control ergonomic risks among female cashiers working in a department store belonging to the retail market. This study was conducted between May and November 2010. Participatory ergonomics was applied through knowing and understanding how the company works, establishing the work team (Ergo group), training the team in ergonomics-related topics, and making decisions and interventions. The sample was composed of 71 participants--mostly female cashiers--, and all of them have a musculoskeletal compromise, declaring pain or discomfort mainly in the neck, lower back, right wrist and shoulders. Among others, following problems were found: postural overload, repetitive work, manual load handling, mental fatigue, environmental discomfort, variable work schedules, extended working days, and absence of breaks. In the intervention, the main implemented changes were the redesign of workstation, complete change of chairs and keyboards, and the implementation of a rotation system, as well breaks for compensatory exercises. After that, an evident improvement of found problems was observed, therefore it can be concluded that participatory ergonomics is an attractive methodology, appropriate and efficient for solving and controlling ergonomic risks and problems.     

Comparing two types of navigational interfaces for Virtual Reality

Previous studies suggest significant differences between navigating virtual environments in a life-like walking manner (i.e., using treadmills or walk-in-place techniques) and virtual navigation (i.e., flying while really standing). The latter option, which usually involves hand-centric devices (e.g., joysticks), is the most common in Virtual Reality-based studies, mostly due to low costs, less space and technology demands. However, recently, new interaction devices, originally conceived for videogames have become available offering interesting potentialities for research. This study aimed to explore the potentialities of the Nintendo Wii Balance Board as a navigation interface in a Virtual Environment presented in an immersive Virtual Reality system. Comparing participants' performance while engaged in a simulated emergency egress allows determining the adequacy of such alternative navigation interface on the basis of empirical results. Forty university students participated in this study. Results show that participants were more efficient when performing navigation tasks using the Joystick than with the Balance Board. However there were no significantly differences in the behavioral compliance with exit signs. Therefore, this study suggests that, at least for tasks similar to the studied, the Balance Board have good potentiality to be used as a navigation interface for Virtual Reality systems.     

Ergonomic and individual risk evaluation

The ergonomic risks constitute a vital aspect of study and prevention for the worker's health, especially for people with different capacities. Very job has and implies certain type of risk for the worker's health, depending on the conditions it is done with the use of tools or without them. Aplicated techniques: posturogram, baropodometry, Schober test, biocinemátic chain test, Fukuda test, propioceptiva plataform in personnel with special capabilities.     

A polynomial equation to predict low back compression force: accounting for the effects of load height on instability

The purpose of this study was to develop a regression equation that, incorporating the potential energy of the load in the hands, was capable of improved predictions of spinal compression forces. A stepwise polynomial equation was developed from EMG profiles of 15 muscles, and its spinal joint loading predictions at L4/L5 were compared to current methods of calculating spinal compression. Absolute muscle activation was shown to increase with increased loading height, indicating that the central nervous system responds to changes in spinal stability. The inclusion of potential energy into the calculation of spinal disc compression at L4/L5 improved estimates of the compressive forces acting on the spine. This is the first model to incorporate potential energy into a predictive model for lumbar spine compression without the use of electromyography. It was concluded that potential energy plays a vital role in dictating the recruitment patterns of the trunk.     

Ergonomics and design: traffic sign and street name sign

This work proposes a design methodology using ergonomics and anthropometry concepts applied to traffic sign and street name sign projects. Initially, a literature revision on cognitive ergonomics and anthropometry is performed. Several authors and their design methodologies are analyzed and the aspects to be considered in projects of traffic and street name signs are selected and other specific aspects are proposed for the design methodology. A case study of the signs of "Street of Antiques" in Porto Alegre city is presented. To do that, interviews with the population are made to evaluate the current situation of signs. After that, a new sign proposal with virtual prototyping is done using the developed methodology. The results obtained with new interviews about the proposal show the user satisfaction and the importance of cognitive ergonomics to development of this type of urban furniture.