Cognitive representation of the comprehension test of safety warnings using multivariate methods

This paper presents a multivariate method to assess the comprehension of safety signs. The proposed method uses the MDS and Procrustes, to obtain a consensus perceptual map. The results show that the map allowed discriminating signs with high levels of comprehension from others. The safety signs have no statistical difference as depicted by Bootstrap Analysis.     

Are cutout handles used when available in real occupational settings? Description of grips and upper extremities movements during industrial box handling

In order to achieve better postures and decrease musculoskeletal risks adequate design of hand/box couplings for manual materials handling (MMH) are still needed. No studies evaluating upper limb movement thorough direct measurements during box handling in workplace were identified in the literature. In this study we describe the types of grip and movements adopted by ten workers when handling redesigned boxes with cutout handles between different heights on industrial pallets. The new handles were used by 90% of the workers through different types of grip. Electrogoniometric measurements showed relatively safe forearm and wrist movements, although elbow inadequate range of movement was recorded. Despite the good acceptance of the cutout by workers, the new design requires extra internal space in the boxes reducing applications for this alternative of box.     

Inclusion of people with disabilities in the production system of a footwear industry

This article presents a study on the inclusion of people with disabilities (mainly mental impairment) in the workforce of a shoe company. The items that could impact on the success of inclusion were identified, and this included employees and other individuals taking part in the process. The inclusion process identified the interests, likes and dislikes of each employee with disabilities and correlated these with the activities available in the company. The case study evaluated the quality of the inclusion through interviews, questionnaires and an assessment of production efficiency. The results showed that inclusion did not adversely affect production, and highlighted that staff with disabilities do their work correctly. According to all employees interviewed, the inclusion of staff with disabilities improved the relationship of the boss with all of the staff and also led to the work environment being enhanced. The final evaluation is that the company's policy of inclusion succeeded.     

A comprehensive literature review of the pelvis and the lower extremity FE human models under quasi-static conditions

Finite Element Modeling (FEM) has become a vital tool in the automotive design and development processes. FEM of the human body is a technique capable of estimating parameters that are difficult to measure in experimental studies with the human body segments being modeled as complex and dynamic entities. Several studies have been dedicated to attain close-to-real FEMs of the human body (Pankoke and Siefert 2007; Amann, Huschenbeth et al. 2009; ESI 2010). The aim of this paper is to identify and appraise the state-of-the art models of the human body which incorporate detailed pelvis and/or lower extremity models. Six databases and search engines were used to obtain literature, and the search was limited to studies published in English since 2000. The initial search results identified 636 pelvis-related papers, 834 buttocks-related papers, 505 thigh-related papers, 927 femur-related papers, 2039 knee-related papers, 655 shank-related papers, 292 tibia-related papers, 110 fibula-related papers, 644 ankle-related papers, and 5660 foot-related papers. A refined search returned 100 pelvis-related papers, 45 buttocks-related papers, 65 thigh-related papers, 162 femur-related papers, 195 knee-related papers, 37 shank-related papers, 80 tibia-related papers, 30 fibula-related papers and 102 ankle-related papers and 246 foot-related papers. The refined literature list was further restricted by appraisal against a modified LOW appraisal criteria. Studies with unclear methodologies, with a focus on populations with pathology or with sport related dynamic motion modeling were excluded. The final literature list included fifteen models and each was assessed against the percentile the model represents, the gender the model was based on, the human body segment/segments included in the model, the sample size used to develop the model, the source of geometric/anthropometric values used to develop the model, the posture the model represents and the finite element solver used for the model. The results of this literature review provide indication of bias in the available models towards 50th percentile male modeling with a notable concentration on the pelvis, femur and buttocks segments.     

Cognitive structure of occupational risks represented by a perceptual map

The main focus of risk management is technical and rational analysis about the operational risks and by those imposed by the occupational environment. In this work one seeks to contribute to the risk perception study and to better comprehend how a group of occupational safety students assesses a set of activities and environmental agents. In this way it was used theory sustained by psychometric paradigm and multivariate analysis tools, mainly multidimensional scaling, generalized Procrustes analysis and facets theory, in order to construct the perceptual map of occupational risks. The results obtained showed that the essential characteristics of risks, which were initially splited in 4 facets were detected and maintained in the perceptual map. It was not possible to reveal the cognitive structure of the group, because the variability of the students was too high. Differences among the risks analyzed could not be detected as well in the perceptual map of the group.     

Reducing whole body vibration in forklift drivers

Forklift drivers in warehouses are often exposed to whole body vibration (WBV) during the total day. There is however an association between working as a forklift operator and the development of low back pain. In this study the exposure to WBV was measured in five forklift drivers who performed a standardised order picking task during 10 minutes. The effect of driving surface (uneven concrete vs. new flat concrete), driving speed (15 km/h vs. 8 km/h) and seat suspension (mechanical suspension vs. air suspension) was investigated. Improving the driving surface was the most effective preventive measure by reducing the whole body vibration with 39%, from 1.14 to 0.69 m/s2. Lowering the speed limit resulted in a reduction of WBV with 26% (1.05 vs. 0.78 m/s2). An air suspension seat was 22% more effective compared to mechanical suspension (1.02 vs. 0.80 m/s2). On uneven concrete an air suspension seat performed even better by reducing the WBV by 29% (1.33 vs. 0.95 m/s2). A combination of a new driving surface, limiting the maximum speed and the introduction of an air suspension seat reduced the whole body vibrations below the action limit of 0.5 m/s2 as mentioned in the European directive. None of the interventions were effective enough on their own.     

Associations between psychosocial risk factors and musculoskeletal disorders: application to the IT profession in India

The exponential growth of the information technology (IT) industry in India has been accompanied with a substantial increase in the reporting of work-related musculoskeletal disorders (WMSDs). The purpose of the current study was to identify and assess the contributions of prevalent psychosocial factors on perceived WMSD outcomes among IT professionals from India. About 77 IT professionals from India completed a survey set consisting of 26 question items from the Job Content Questionnaire and 3 separate question items pertaining to WMSD outcomes (pain/discomfort and psychological stress scores). The findings suggest prevalence of existing pain (shoulder/neck and low back) in more than one-fourth of the respondents. Additionally two-thirds of the respondents had never had any ergonomics awareness training. Co-worker support and psychological work demands were found to be the strongest contributors of psychosocial risk factors towards pain/discomfort and psychological stress outcomes. Findings from this study highlight the influence of certain psychosocial traits of the Indian IT workplace on perceived WMSD outcomes. There is a need to develop and implement intervention strategies to address these factors that may help lower the risk of work-related musculoskeletal pain.     

State of scientific knowledge about the need of recovery time at specific workplaces and recommendations for further research

Research activities to determine the need of recovery time at work were mainly performed in the 1970s and 1980s. Previous studies were largely based on expert opinions or were generated within small and non-representative groups. Often, laboratory experiments were carried out with a low number of subjects. Especially during the last decade, only little additional scientific knowledge was generated on this topic. The very resource intensive development of more detailed results based on the existing level of scientific knowledge is assumed as one reason for this. In general, it seems to be reasonable to continue further research on the knowledge generated in previous studies, but implement larger samples and more representative groups. Besides, according to monotonous manual work, more research is especially needed regarding relative operating forces and operation frequencies taken grip conditions and hand/body position into account.