Time--a key issue for musculoskeletal health and manufacturing.

Time is a key issue for both ergonomists and engineers when they engage in production system interventions. While not their primary purpose, the actions of engineers have major effects on biomechanical exposure; possibly of much greater magnitude than many ergonomics interventions. This paper summarises the aims, actions and tools of engineers and ergonomists, emphasising time-related outcomes. Activities of the two groups when attempting to manipulate time aspects of work may be contradictory; engineers wishing to improve production and ergonomists aiming at better health as well as contributing to production. Consequently, tools developed by ergonomists for assessing time aspects of work describe rest patterns, movement velocities or daily duration of exposures, while engineering tools emphasise time-efficient production. The paper identifies measures that could be used to communicate time-relevant information between engineers and ergonomists. Further cooperation between these two stakeholders as well as research on the topic are needed to enable ergonomists to have a larger impact on the design of production systems.

[1]  L Beech-Hawley,et al.  A multi-method approach to assessing deadlines and workload variation among newspaper workers. , 2004, Work.

[2]  W. G. Allread,et al.  The Role of Dynamic Three-Dimensional Trunk Motion in Occupationally-Related Low Back Disorders: The Effects of Workplace Factors, Trunk Position, and Trunk Motion Characteristics on Risk of Injury , 1993, Spine.

[3]  Fred E. Meyers.  Motion and Time Study: Improving Work Methods and Management , 1992 .

[4]  L. Forcier,et al.  Work related musculoskeletal disorders (WMSDs) : a reference book for prevention , 1995 .

[5]  A Garg,et al.  Revised NIOSH equation for the design and evaluation of manual lifting tasks. , 1993, Ergonomics.

[6]  J. Winkel,et al.  Occupational and individual risk factors for shoulder-neck complaints: Part II — The scientific basis (literature review) for the guide , 1992 .

[7]  S. Linton.  New avenues for the prevention of chronic musculoskeletal pain and disability , 2002 .

[8]  D. Rempel,et al.  VDT-related musculoskeletal symptoms: interactions between work posture and psychosocial work factors. , 1994, American journal of industrial medicine.

[9]  S. Mathiassen,et al.  On the evolution of task-based analysis of manual materials handling, and its applicability in contemporary ergonomics. , 2006, Applied ergonomics.

[10]  W S Marras,et al.  Biomechanical risk factors for occupationally related low back disorders. , 1995, Ergonomics.

[11]  Ann-Christine Falck,et al.  Modified method time measurements for ergonomic planning of production systems in the manufacturing industry , 2000 .

[12]  J. Winkel,et al.  Towards optimizing physical activity in VDT/office work , 1991 .

[13]  R. Westgaard.  Measurement and evaluation of postural load in occupational work situations , 2004, European Journal of Applied Physiology and Occupational Physiology.

[14]  J. Winkel,et al.  Validity of self-assessed reports of occurrence and duration of occupational tasks , 2005, Ergonomics.

[15]  J Petzäll,et al.  Ergonomics in parallelized car assembly: a case study, with reference also to productivity aspects. , 1996, Applied ergonomics.

[16]  S H Snook,et al.  The design of manual handling tasks: revised tables of maximum acceptable weights and forces. , 1991, Ergonomics.

[17]  C. Wiktorin,et al.  Validity of self-reported exposures to work postures and manual materials handling. Stockholm MUSIC I Study Group. , 1993, Scandinavian journal of work, environment & health.

[18]  Svend Erik Mathiassen,et al.  Efficient one-day sampling of mechanical job exposure data--a study based on upper trapezius activity in cleaners and office workers. , 2003, AIHA journal : a journal for the science of occupational and environmental health and safety.

[19]  R. D. Ray,et al.  Trends in Ergonomics/Human Factors II , 1985 .

[20]  Svend Erik Mathiassen,et al.  Variability in mechanical exposure within and between individuals performing a highly constrained industrial work task , 2003, Ergonomics.

[21]  Waldemar Karwowski.  Ergonomics and Production Philosophies , 2006 .

[22]  Christian Berggren.  Alternatives to Lean Production: Work Organization in the Swedish Auto Industry , 1993 .

[23]  R G Radwin,et al.  Agreement between a frequency-weighted filter for continuous biomechanical measurements of repetitive wrist flexion against a load and published psychophysical data. , 1998, Ergonomics.

[24]  Roland Örtengren,et al.  MTM-based ergonomic workload analysis , 2002 .

[25]  Roland Örtengren,et al.  ErgoSAM: A preproduction risk identification tool , 2005 .

[26]  J Winkel,et al.  Ergonomic effects of a management-based rationalization in assembly work - a case study. , 1996, Applied ergonomics.

[27]  Lawrence J. Fine,et al.  Repetitive Motion Disorders of the Upper Extremity , 1995 .

[28]  Udo W. Pooch,et al.  Discrete Event Simulation: A Practical Approach , 1992 .

[29]  E Grandjean,et al.  Postural and visual loads at VDT workplaces. I. Constrained postures. , 1981, Ergonomics.

[30]  R Kadefors,et al.  A Swedish industrial research program 'Co-operative for Optimization of Industrial Production Systems Regarding Productivity and Ergonomics' (COPE). , 1999, American journal of industrial medicine.

[31]  Svend Erik Mathiassen,et al.  Diversity and variation in biomechanical exposure: what is it, and why would we like to know? , 2006, Applied ergonomics.

[32]  Håkan Johansson,et al.  Chronic Work-Related Myalgia : Neuromuscular Mechanisms behind Work-Related Chronic Muscle Pain Syndromes , 2003 .

[33]  N Moray,et al.  Culture, politics and ergonomics , 2000, Ergonomics.

[34]  S. Kumar,et al.  Cumulative Load as a Risk Factor for Back Pain , 1990, Spine.

[35]  H Hemingway,et al.  Organisational downsizing and musculoskeletal problems in employees: a prospective study , 2001, Occupational and environmental medicine.

[36]  Jaana Pentti,et al.  Effect of organisational downsizing on health of employees , 1997, The Lancet.

[37]  T. Armstrong,et al.  Cross-sectional study of the relationship between repetitive work and the prevalence of upper limb musculoskeletal disorders. , 1999, American journal of industrial medicine.

[38]  Stephan Konz,et al.  Work/rest: Part II The scientific basis (knowledge base) for the guide 1 The recommendations provi , 1998 .

[39]  P Asterland,et al.  A method for evaluation of manual work using synchronised video recordings and physiological measurements. , 2002, Applied ergonomics.

[40]  Richard P Wells,et al.  The effects of job rotation on the risk of reporting low back pain , 2003, Ergonomics.

[41]  Å. Kilbom,et al.  Repetitive work of the upper extremity: Part II — The scientific basis (knowledge base) for the guide , 1994 .

[42]  Don B. Chaffin,et al.  Working Postures and Movements: Tools for Evaluation and Engineering , 2005 .

[43]  Thomas J Armstrong,et al.  Evaluation of three methodologies for assessing work activity during computer use. , 2003, AIHA journal : a journal for the science of occupational and environmental health and safety.

[44]  R. Wells,et al.  The time variation pattern of mechanical exposure and the reporting of low back pain , 2008 .

[45]  J Winkel,et al.  A model for solving work related musculoskeletal problems in a profitable way. , 1996, Applied ergonomics.

[46]  Jörgen Winkel,et al.  Validity of self-reported exposures to work postures and manual materials handling , 1993 .

[47]  Jan Forslin,et al.  Creating sustainable work systems : emerging perspectives and practice , 2002 .

[48]  D Colombini,et al.  An observational method for classifying exposure to repetitive movements of the upper limbs. , 1998, Ergonomics.

[49]  W Karwowski,et al.  The boundaries for joint angles of isocomfort for sitting and standing males based on perceived comfort of static joint postures , 2001, Ergonomics.

[50]  Jacques Malchaire,et al.  Relationship between work constraints and the development of musculoskeletal disorders of the wrist: A prospective study , 1997 .

[51]  D B Chaffin,et al.  Improving digital human modelling for proactive ergonomics in design , 2005, Ergonomics.

[52]  Svend Erik Mathiassen,et al.  Interactive effect of ergonomics and production engineering on shoulder-neck exposure — A case study of assembly work in China and Sweden , 1997 .

[53]  S. Konz.  Work/rest: Part II – The scientific basis (knowledge base) for the guide1 , 2000 .

[54]  Daniel T. Jones,et al.  The machine that changed the world : based on the Massachusetts Institute of Technology 5-million dollar 5-year study on the future of the automobile , 1990 .

[55]  Svend Erik Mathiassen,et al.  Task-based estimation of mechanical job exposure in occupational groups. , 2005, Scandinavian journal of work, environment & health.

[56]  Richard Wells,et al.  Mechanical exposure concepts using force as the agent. , 2004, Scandinavian journal of work, environment & health.

[57]  M. Frings-Dresen,et al.  Effect of job rotation on need for recovery, musculoskeletal complaints, and sick leave due to musculoskeletal complaints: a prospective study among refuse collectors. , 2005, American journal of industrial medicine.

[58]  Svend Erik Mathiassen,et al.  Job enlargement and mechanical exposure variability in cyclic assembly work , 2004, Ergonomics.

[59]  D M Andrews,et al.  Comparison of four peak spinal loading exposure measurement methods and their association with low-back pain. , 1999, Scandinavian journal of work, environment & health.

[60]  Svend Erik Mathiassen,et al.  A case study evaluating the ergonomic and productivity impacts of partial automation strategies in the electronics industry , 2002 .

[61]  W S Marras,et al.  Wrist motions in industry. , 1993, Ergonomics.

[62]  Steven L. Sauter,et al.  Promoting health and productivity in the computerized office : models of successful ergonomic interventions , 1990 .

[63]  D B Chaffin,et al.  Shoulder disorders and postural stress in automobile assembly work. , 2000, Scandinavian journal of work, environment & health.

[64]  Don B. Chaffin,et al.  Digital Human Modeling for Vehicle and Workplace Design , 2001 .

[65]  S H Snook,et al.  Challenges in assessing risk factors in epidemiologic studies on back disorders. , 1997, American journal of industrial medicine.

[66]  神代 雅晴,et al.  Towards human work : solutions to problems in occupational health and safety , 1991 .

[67]  V. H. Hildebrandt,et al.  Psychosocial factors at work and musculoskeletal disease , 1993 .

[68]  T J Armstrong,et al.  Hand wrist cumulative trauma disorders in industry. , 1986, British journal of industrial medicine.

[69]  K. J. Vicente,et al.  Cognitive Work Analysis: Toward Safe, Productive, and Healthy Computer-Based Work , 1999 .

[70]  Patrick G Dempsey,et al.  A survey of tools and methods used by certified professional ergonomists. , 2005, Applied ergonomics.

[71]  J P Bonde,et al.  Work related shoulder disorders: quantitative exposure-response relations with reference to arm posture , 2004, Occupational and Environmental Medicine.

[72]  Waldemar Karwowski,et al.  Human performance in lean production environment: Critical assessment and research framework , 2003 .

[73]  G. Boothroyd,et al.  Design for assembly , 1993, IEEE Spectrum.

[74]  Jeffrey K. Liker,et al.  The Toyota way : 14 management principles from the world's greatest manufacturer , 2004 .

[75]  R. Norman,et al.  A comparison of peak vs cumulative physical work exposure risk factors for the reporting of low back pain in the automotive industry. , 1998, Clinical biomechanics.

[76]  S E Mathiassen,et al.  Quantifying variation in physical load using exposure-vs-time data. , 1991, Ergonomics.

[77]  W Rohmert,et al.  Problems of determination of rest allowances Part 2: determining rest allowances in different human tasks. , 1973, Applied ergonomics.

[78]  Li Lin,et al.  An integrated methodology for manufacturing systems design using manual and computer simulation , 2003 .

[79]  R. H. Westgaard,et al.  Ergonomic intervention research for improved musculoskeletal health: A critical review , 1997 .

[80]  W. M. Keyserling,et al.  Back disorders and nonneutral trunk postures of automobile assembly workers. , 1991, Scandinavian journal of work, environment & health.

[81]  Svend Erik Mathiassen,et al.  Production system design elements influencing productivity and ergonomics - A case study of parallel and serial flow strategies , 2006 .

[82]  P. Landsbergis,et al.  The impact of lean production and related new systems of work organization on worker health. , 1999, Journal of occupational health psychology.

[83]  S E Mathiassen,et al.  Assessment of physical work load in epidemiologic studies: concepts, issues and operational considerations. , 1994, Ergonomics.

[84]  Shrawan Kumar,et al.  Computer applications in ergonomics, occupational safety and health: edited by Markku Mattila and Waldemar Karwowski. Proceedings of the International Conference on Computer-Aided Ergonomics and Safety, Tampere, Finland, 18–20 May, 1992. Elsevier Science B.V. (North-Holland), Amsterdam, The Netherla , 1995 .

[85]  J Pentti,et al.  Factors underlying the effect of organisational downsizing on health of employees: longitudinal cohort study , 2000, BMJ : British Medical Journal.

[86]  R. Westgaard,et al.  Electromyographic evaluation of muscular work pattern as a predictor of trapezius myalgia. , 1993, Scandinavian journal of work, environment & health.

[87]  Lars Medbo,et al.  A case study of a principally new way of materials kitting an evaluation of time consumption and physical workload , 2002 .

[88]  Svend Erik Mathiassen,et al.  An integrated analysis of ergonomics and time consumption in Swedish 'craft-type' car disassembly. , 2005, Applied ergonomics.