Karlheinz Schaub

The European Assembly Worksheet

Assembly tasks are most common in industrialised countries. Even in highly automated and mechanised branches like the automotive, high or uniform load situations are common and result in high physical workload. In industrialised countries almost one-third of the total sick leave is due to musculo-skeletal complaints and disorders, which might result from poor ergonomic design. In order to tackle that problem, the European Assembly Worksheet (EAWS) as a screening tool for physical workload was developed. The EAWS grants load points for unfavourable physical workload and due to the total score assigns a traffic light risk scheme to work situations. In the recent years, the EAWS was checked for compliance with existing internationally accepted methods and legal European requirements. In the companies involved, the EAWS serves as an ergonomic screening tool. It links corrective (shop floor) and proactive (Tech center) ergonomics, points out ergonomic problems and offers design solutions to overcome them.

A computer-aided tool for ergonomic workplace design and preventive health care

Preventive health care is one of the basic challenges facing ergonomics. The aim to prevent occupationally generated musculoskeletal disorders and diseases may be achieved by appropriate workplace and product design. ERGOMan is a computer-aided 3D man model suitable for ergonomic and movement simulation at industrial workstations. Within a common project of the above mentioned institutions ERGOMans inventory of ergonomics design tools shall be enhanced in a way that ERGOMan will be able to give detailed information on load or stress situations, which might effect the executability and tolerability of work situations with high probability.

Ergonomic Screening of Assembly Tasks in Automotive Industries

The screening tool “Design Check” (DC) allows the detection of ergonomic deficits in workplace layouts. DC was recently developed in a joint research project of the Ergonomics Institute, Darmstadt University of Technology (IAD) and Porsche AG, Stuttgart, promoted by the German Federal Ministry of Technology (BMBF). DC focuses onto the evaluation of industrial work tasks with special respect to assembly tasks. The checklist was designed to identify risk situations generated by physical workplace demands. DC was developed and tested at the assembly lines of Porsche automotive industries, Stuttgart, Germany.

Modular Concepts for Integrating Ergonomics into Production Processes

It is a major concern of ergonomics to align humanity with economic efficiency. Ergonomic approaches that are introduced after the requests from employees or even worse after the first diagnoses of work-related health problems follow a corrective manner, and therefore cannot fulfill this concern. Especially the integration of corrective measures into completed work design is in most cases difficult and high priced. Absence due to illness of staff members is connected to premium rates, breaking-in costs of new staff members, capital expenditure, insurance contributions of possible unused capital equipment, or increased costs for planning and controlling on the side of management. In addition, there are costs of potential production downtimes and quality defects (LANDAU 2002). But even the reintegration into occupational environment of a sick staff member is related to costs when the employee has to be introduced to a new or redesigned workplace. Although, there are many companies (especially small and medium-sized enterprises, SME) that lack of methods and concepts for the integration of effective structures for a preventive-oriented health and safety management. Hence, occupational and outside occupational stakeholders have to have methods and management instruments that support re-orientation at new task areas. To fulfill the demand for conceptual instead of corrective ergonomics it is necessary to align ergonomic methods and findings for analysis and design of work systems with the established processes in companies for product development and production planning.

Ergonomic Vehicle Development Process and Production at Adam Opel Ag (GM-EUROPE) with Respect to European Legislation

During the recent 10 years several EU Directives for the improvement of ergonomics and health and safety at work have been implemented. In order to comply with these regulations (during production as well as in the design phase) a “New Production Worksheet” (NPW) has been created in a joint research project of the International Technical Development Center (ITDC) of Adam OPEL AG, Rüsselsheim and the Ergonomics Institute, Darmstadt University of Technology (IAD). This worksheet is based on relevant EU Directives, existing GM Europe methodology and other international methods, that reflect the current state of the art in Ergonomics. The NPW was developed and tested at the Vectra assembly line at the OPEL Rüsselsheim Plant.

Musculo-Skeletal Loads on Flight Attendants when Pushing and Pulling Trolleys aboard Aircraft

In the context of an extensive cross-sectional study, the physical strength and biometric data of about 500 flight attendants in Germany and the handling of trolleys on planes and in the laboratory have been investigated biomechanically. 25 selected flight attendants took part in the laboratory study, which comprised measurements of posture, action force and the calculation of the lumbar spinal load from the pushing and pulling of trolleys in a variety of configurations. The population of flight attendants differs from other professional groups in terms of age and sex distribution and maximum strength. The stressing of the musculo-skeletal system from pushing and pulling depends essentially on the trolley load and on the gradient of the cabin floor. In addition, the degree of stressing depends significantly on the trolley type, mode of handling and personal dexterity. The compression forces on the lumbar spine from pulling a trolley were up to double that from pushing and peaked at up to 3 kN. The results demonstrate that female flight attendants are likely to overload themselves if they frequently have to move loaded trolleys unaided on a cabin floor at a gradient of over 2°.

ISO/FDIS 11226: Evaluation of Static Working Postures

The authors constitute the writing group of ISO/TC159/SC3/WG2 for ISO 11226. This paper describes ISO/FDIS 11226, the international standard on evaluation of static working postures. The scope, the evaluation procedure, and the current status are described.

Analysis and Evaluation of Physical Workload During Long-Cyclic Tasks as a Prerequisite for Ergonomic Work Design

Evaluation of physical workload such as the screening tool Ergonomic Assessment Worksheet (EAWS) were developed and validated for use in industrial manufacturing with short cycles (up to 3 min). If this tool is used for work stations that have significantly longer cycles or no cycle at all, its use is limited. On the one hand, measuring the workload intensity becomes increasingly expensive. On the other hand, the workload intensity for these scenarios has to be examined as well. The following contribution presents an instance of how the EAWS can be used for long-cycle tasks on the example of a maintenance workplace at Deutsche Bahn. This work is focused on methods for adapted data collection from which indicators for possible adjustments to the evaluation procedure can be concluded.

Development of a database for capability-appropriate workplace design in the manufacturing industry

BACKGROUND: Due to demographic change, less young workers are available and the overall number of workers will decrease. The length of absenteeism, especially due to musculoskeletal disorders, increases with higher age. OBJECTIVE: The range of performance between individuals grows wider although there are exceptions for different capabilities and elderly workers. Therefore, a capability-appropriate workplace design is necessary to meet physical workplace demands in the manufacturing industry and in order to preserve the workability of the workforce. METHODS: The human-centred design process was used to provide a design solution that meets the needs of the workplace designers. The design solutions are evaluated three times. RESULTS: The high number of capabilities with a wide range of individual performance can be best captured and represented in a database. Therefore, a database is developed in which relevant physical manufacturing capabilities are collected and processed for workplace designers. Based on this information, design solutions for a prospective capability-appropriate workplace design can be derived relative to the age structure of the manufacturing plant. CONCLUSIONS: This gives the workplace designer propositions on how to plan their workplaces so as to avoid excessive stress and musculoskeletal disorders in the employees.

Biomechanische Gefährdungsbeurteilung bei Montagearbeitsplätzen

ZusammenfassungIm Rahmen eines Forschungsprojektes („KoBRA“; Kugler et al. 2011) sollte die Analyse von Montagetätigkeiten mithilfe von ausgewählten Bewertungswerkzeugen um eine biomechanische Bewertung und Risikoeinschätzung erweitert werden. Als Bewertungswerkzeuge wurden die in der Kraftfahrzeugindustrie erprobten „Papier- und Bleistiftsysteme“ „AAWS“ (Schaub 2004) und „EAWS“ (Schaub & Ghezel-Amadi 2007; Schaub et al. 2012) ausgewählt und zu jedem der mit diesen Werkzeugen analysierbaren Tätigkeitselemente die biomechanische Belastung der Lendenwirbelsäule (LWS) unter der Annahme definierter Tätigkeitsbedingungen berechnet. Die Ergebnisse wurden mit Empfehlungen zur maximalen Kompressionsbelastung der LWS („Dortmunder Richtwerte“; Jäger et al. 2001) verglichen und daraufh in einer Kategorie des Schädigungsrisikos zugeordnet.AbstractIn the context of a funding program of the Federal Ministry of Labour and Social Affairs for controlling work-induced diseases (”Load on the musculoskeletal systems at work–Conversion of integrative prevention approaches into practice”), the ”Cooperative initiative to normative management of load and risk at physical work–KoBRA“ (Kugler et al. 2011) was established. Supplementary evaluation and assessment of selected assembly tasks should be enabled by means of applying biomechanical criteria and methods in a sub-project of KoBRA in order to support avoidance of impairments or injuries of the lumbar spine and to provide a work-design aid for practice simultaneously (Hecktor 2011). Thereby, a biomechanical analysis including risk estimation was performed for all tasks mentioned in well-known assessment tools regarding the respective variables such as posture and load weight. Assessment tools like the European Assembly Worksheet EAWS (version 1.3.2; Schaub & Ghezel-Ahmadi 2007; Schaub et al. 2012), which is a screening method for analyzing assembly work, represented the starting point of analysis. The factors ”posture”, ”action forces”, ”object handling“ and ”repetitive loads of the upper extremities“ can be analyzed by applying the EAWS, furthermore, the risk of impairments or injuries can be estimated and is, then, categorized via a traffic-light scheme (green: low risk; yellow: potential risk; red: probable risk). Compressive force FC acting on the lowest compound of vertebrae and intervertebral disc within the lumbar spine (L5-S1) served as indicator of lumbar- spine load. Recommended limits of maximal compressive strength of lumbar-spine segments, the so-called Dortmund Recommendations (Jäger et al. 2001) were used as criterion for risk estimation.