Ergonomics

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Andrew Pinder, Health & Safety Laboratory, UK


Introduction

This article presents an overview of the relationship of Ergonomics (also known as Human Factors) to occupational safety and health (OSH). It describes briefly the historical background of Ergonomics. It describes how ergonomics can be applied to OSH and how it fits with the legislative framework for OSH in the European Union. It summarises the application areas of Ergonomics that relate to OSH and lists professional bodies in ergonomics and current sources of information.

Definition

According to the official definition of the International Ergonomics Association (IEA)[1], ‘Ergonomics (or human factors) is the scientific discipline concerned with the understanding of the interactions among humans and other elements of a system’. The terms ‘Ergonomics’ and ‘Human Factors’ are therefore synonyms and can be used interchangeably, although some do regard them as separate (but complementary) entities. These terms also refer to ‘the profession that applies theoretical principles, data and methods to design in order to optimise human well-being and overall system performance.’ [1].

Four fundamental characteristics of ergonomics can be deduced from these definitions: Ergonomics

  • takes a systems approach (the system includes the cultural and physical environment, the organisation and the specific task requirements);
  • is design driven (an analysis results in new or redesigned approaches, recommendations, workplace and tool design);
  • is an iterative, human-centred process (users are a resource for developing knowledge and testing solutions);
  • focuses on performance as well as on well-being (optimising efficiency, effectiveness, health and safety and job enjoyment).

Ergonomics is a systems-oriented discipline, which can be applied to all aspects of human activity. In the context of work system, standard ISO 6385 establishes the fundamental principles of ergonomics as basic guidelines for the design of work systems[2]. In the wider context, standard ISO 26800 presents the general ergonomics approach and specifies basic ergonomics principles and concepts applicable to the design and evaluation of tasks, jobs, products, tools, equipment, systems, organisations, services, facilities and environments[3]. Ergonomists often work in particular economic sectors or application domains, which are not mutually exclusive and change over time [1].

Historical background

Origins of the term ‘ergonomics’

The word ‘ergonomics ‘ was coined in 1949 by K. F. H Murrell as a combination of two Greek words, εργον (ergon), meaning ‘work ‘, and νομος (nomos) meaning ‘law’[4]. It came to prominence in 1950 when it was used in the name of the ‘Ergonomics Research Society’ (now the Chartered Institute of Ergonomics and Human Factors).

In the 19th century the same term had been coined independently in Poland by Wojciech Jastrzębowski[5] who published Rys ergonomji czyli nauki o pracy, opartej na prawdach poczerpniętych z Nauki Przyrody (The Outline of Ergonomics, i.e. Science of Work, Based on the Truths Taken from the Natural Science) (1857).

Origin of the term ‘human factors’

The terms ‘Human Engineering’, ‘Human Factors’ and ‘Human Factors Engineering’ came into use in the USA during World War 2 in the context of the design of military equipment[6].

Profession

Practitioners of ergonomics, 'ergonomists', are defined as professionals who 'contribute to the planning, design, implementation, evaluation, redesign and continuous improvement of tasks, jobs, products, technologies, processes, organisations, environments and systems in order to make them compatible with the needs, abilities and limitations of people.’[1]

The IEA has defined the core competencies, knowledge and skills of ergonomists that are used for developing curricula in ergonomics, assessment of competences, certification of professionals, etc.[7] The IEA endorses certification bodies [28] that certify ergonomists based on the core competencies, e.g. the Centre for Registration of European Ergonomists (CREE [29] ). The CREE specifies the standard of knowledge and practical experience required for registration as a European Ergonomist.

Relationship of ergonomics to OSH

Ergonomics is a discipline that can be applied to OSH to help ensure that workplace risks are, prevented at the design stage, eliminated at a later stage, or controlled and reduced if they cannot be eliminated. It can therefore improve the safety, well-being and comfort of workers. It also has broader effects by enhancing the safety of systems of work and therefore, more broadly, of society as a whole. In the specific context of the safety of machinery the need to accommodate ergonomics principles is embodied in ISO 12100[8] and ISO/TR 22100-3[9] provides a more detailed framework for incorporating ergonomics in the design of machines to help ensure their safety.

Legislative frameworks relating to OSH and ergonomics

The most important piece of European legislation relevant to risk assessment is the ‘Framework Directive’[10]. This Directive has been transposed into national legislation. Member States, however, have the right to introduce more stringent provisions to protect their workers.

Article 6 of the Framework Directive encourages an ergonomic approach since it requires the employer to adapt the work to the individual, particularly by alleviating monotonous work and work at a predetermined work-rate and by reducing the effect of work on health. Six individual directives[11] [12] [13] [14] [15] [16] were initially made under the Framework Directive, with further individual directives being added making a total (2022) of 24 (including the Framework). The Directives on Manual Handling [14], Display Screen Equipment (DSE) [15] and Personal Protective Equipment (PPE), [13] which were all amongst the first six, are of particular importance to ergonomics. Amongst the first six, the directive on work equipment [12] and the provisions regarding thermal conditions in the directive on the requirements for the workplace [11] also relate to ergonomics issues. None of the further individual directives include any additional requirements relevant to ergonomics.

Specific areas of application of ergonomics to OSH

Physical ergonomics

Physical ergonomics is concerned with human anatomical, anthropometric, physiological and biomechanical characteristics as they relate to physical activity. It covers topics such as working postures, manual handling operations, repetitive movements, work-related musculoskeletal disorders (WRMSDs), workplace layout, safety and health [1].

Environmental ergonomics

In addition to the physical design of the working environment, the environment itself (temperature, lighting, noise, etc.) can have a significant effect on the health, safety and performance of workers. For example, elevated temperatures can impair concentration, increasing human error and the risk of accidents, as well as creating a risk of heat-related illness. A series of ISO Standards provide help and guidance on the design and assessment of physical environments.

Anthropometry

Anthropometry is the science of measurement of the human body. It can be applied to OSH to ensure that workers have sufficient space to perform their tasks, that they can reach necessary equipment, tools and controls, that barriers keep them out of reach of hazards, and that working postures can be optimised for the range of people using them[17].

Ergonomic work design

This refers to the use of ergonomics to design jobs and work systems so that most of the potential workforce can perform well. The ultimate goal is to make it easy for quality work to be done easily without unnecessary risk of injury or illness because of biomechanical, physiological or psychological overload[18]. It will therefore tend to improve the reliability of humans within a system and to reduce the risks of harmful errors occurring.

Musculoskeletal disorders

Musculoskeletal disorders (MSDs) can affect the body's muscles, joints, tendons, ligaments, bones and nerves.

Most work-related MSDs develop over time and are caused either by the work itself or by the employees' working environment. They can also result from accidents, e.g. fractures and dislocations. Typically, MSDs affect the back, neck, shoulders and upper limbs; less often they affect the lower limbs.

Health problems range from discomfort, minor aches and pains, to more serious medical conditions requiring time off work and even medical treatment. In more chronic cases, treatment and recovery are often unsatisfactory - the result could be permanent disability and loss of employment.

Many problems can be prevented or greatly reduced by complying with existing safety and health law and following guidance on good practice. This includes assessing the work tasks, putting in place preventive measures, and checking that these measures stay effective [19].

Physiological fatigue

Exercise induced fatigue has a physiological basis. It is thought to be a warning mechanism that prevents overstrain of the body or a part of the body. It can be general or systematic, or local, usually muscular in nature. It is different from mental or visual fatigue. It is important in the context of OSH because it leads to the reduction in the capacity of muscles to generate force or power output, so may make a fatigued worker less able to perform work tasks, less efficient, and more likely to make errors or suffer injury[20].

Cognitive ergonomics

Cognitive ergonomics is concerned with mental processes, such as perception, memory, reasoning, and motor response, as they affect interactions among humans and other elements of a system [1]. It therefore relates to OSH through how people process information in hazardous situations.

Human machine interface

A Human Machine Interface (HMI) can be defined[21] as the part of a machine or device which allows the exchange of information between an operator/user and the machine/device. An HMI consists of three parts which are (1) controls / input devices, (2) displays or other output devices, and (3) an inner structure, often consisting of both hardware and computer software.

Deficiencies in an HMI are relevant to OSH as they can cause stress, errors and accidents. Stress can result from cognitive overload or under-load. Operating errors can result in accidents. In high-risk industries, such as nuclear, oil, or gas such errors can result in major accidents.

The increasing use of artificial intelligence (AI) technologies in workplaces creates opportunities as well as challenges for OSH. AI can impact work processes, working conditions or the work environment[22]. Ergonomics play an essential role for supporting the human-centric design and safe operation of AI[23].

Human error

The two main types of human failure are errors and violations[24]. A human error is an action or decision which was not intended or has an outcome that was unintended. A violation is a deliberate deviation from a rule or procedure. Both types of failure can have the potential to result in harm to people. Errors can be classified as

  • Slips – when something is done that should not have been done;
  • Lapses – when something that should be done is omitted;
  • Mistakes or errors of judgement or decision-making – which may be due to applying rules badly, or having incorrect or insufficient information.

Violations include non-compliances, circumventions, shortcuts and work-arounds.

Ergonomics in office work

While offices are typically low risk environments, ergonomics relates to OSH in office work in the context of seating and low back pain and the need to encourage movement and avoid prolonged static postures, [25] [26] use of VDU equipment, use of computer software, musculoskeletal disorders, thermal environments, psychological demands, work-related stress and visual fatigue [27] [28]. Recent trends in the development of mobile computing and hand-held computing devices raise ergonomics issues because much “office work” is now taking place outside offices.

Other aspects of ergonomics

Organisational ergonomics

Organisational ergonomics is concerned with the optimisation of sociotechnical systems, including their organisational structures, policies, and processes [1]. It takes into account factors ranging from the design of workstations to the scheduling of rest breaks and job rotation schedules to human resources issues such as promotion opportunities. This approach gives an overview of the OSH risks that each person in the system is exposed to.

Participatory ergonomics

‘Participatory ergonomics’ has been defined as ‘The involvement of people in planning and controlling a significant amount of their own work activities, with sufficient knowledge and power to influence both processes and outcomes in order to achieve desirable goals’[29].

Within ergonomics the consensus is that the participation of end users in the design of work equipment and workplaces will lead to better design, as these solutions are developed using the expertise and practical experience of the end users. It is also held that a participatory approach will make the solutions more acceptable to the end users and will improve relations between managers and the workers[30]. Participatory approaches also bring benefits by raising awareness of ergonomic risks in the workplace and encouraging workers to participate in finding solutions and applying them. There are also studies that point to the positive effects in terms of effective reduction of musculoskeletal disorders, injuries or absenteeism, but due to the methodological limitations of these studies, the evidence is limited[31].

Gender differences in the workplace

Physical, physiological, psychological, social and cultural differences between men and women mean that ergonomists need to be aware of the influences these differences can have in the workplace. Selection policies and informal self-selection lead to many jobs and tasks within jobs being more associated with either males or females. Real or perceived differences can be associated with different employment patterns for males and females. Jobs, workstations or equipment associated with male employment may be unsuited to female employees, and vice versa. As men and women tend to have different domestic and caring responsibilities outside work, they may prefer different working patterns and hours of work[32].

Work adaptions for individuals with specific needs

The European employment directive aimed at preventing discrimination[33] requires employers to carry out workplace adaptions for people with disabilities. Ergonomics often has a part to play in the process of making modifications to accommodate these individuals, including facilitating keeping them in work or helping them to return to work following injury or ill health. Council Directive 2000/78/EC establishes a general framework for equal treatment in employment and occupation.


Learned societies and professional bodies

International federations

Table 1: International federations

The International Ergonomics Association [30] is the federation of ergonomics and human factors societies around the world.
IEA Networks are groupings of IEA federated societies, or its affiliates, formed to address specific needs[34]. As of April 2022, these are:

- Asian Council on Ergonomics and Design (ACED) [31];

- ErgoAfrica [32];

- FEES; Federation of European Ergonomics Societies [33];

- Federation of Brazilian, Russian, Indian, Chinese, and South African HF/E Societies (BRICSplus);

- La Unión Latinoamericana de Ergonomía (ULAERGO) [34];

- Nordic Ergonomics and Human Factors Society (NES) [35];

- The South East Asian Network of Ergonomics Societies (SEANES) [36]


Source: IAE

European societies

Table 2: European societies

Austria Österreichische Arbeitsgemeinschaft Für Ergonomie [37]
Belgium Belgian Ergonomics Society (BES) [38]
Croatia Croatian Ergonomics Society [39]
Czech Republic Česká ergonomická společnost (Czech Ergonomics Society, CES) [40]
France Société d'Ergonomie de Langue Française (SELF, French Language Ergonomics Society) [41]
Germany Gesellschaft für Arbeitswissenschaft (GfA) [42]
Greece Ελληνική Εταιρεία Εργονομίας (EEE, Hellenic Ergonomics Society, HES), [43]
Hungary Magyar Ergonómiai Társaság (MET)[44](Hungarian Ergonomics Society [45])
Ireland Irish Ergonomics Society [46]
Italy Società Italiana di Ergonomia (SIE) [47]
Latvia Latvijas Ergonomikas Biedrības (Latvian Ergonomics Society) [48]
Netherlands Human Factors NL [49]
Nordic countries Nordic Ergonomics and Human Factors Society (NES) [50]
Poland Polskie Towarzystwao Ergonomiczne (Polish Ergonomic Association) [51]
Portugal Associação Portuguesa De Ergonomia (APERGO)
Russia Межрегиональная Общественная Организация «Эргономическая Ассоциация» (МЭА) (The Inter-Regional (Russian) Ergonomic Association (IREA)) [52]
Serbia Ergonomics Society of Serbia (ESS)
Slovakia Slovenská ergonomická spoločnosť (SES) (Slovak Ergonomics Association)[53]
Spain Asociación Española de Ergonomía (AEE) [54]
Switzerland Swiss Ergonomics Association [55]
Turkey Turkish Ergonomics Society
Ukraine Всеукраїнська Ергономічна Асоціація (All-Ukrainian Ergonomics Association)
United Kingdom The Chartered Institute of Ergonomics and Human Factors (CIEHF) [56].

Source: IAE

Sources of information

Textbooks

  • Astrand, P.O., Rodahl, K., Dahl, K.A., & Strømme, S.B., Textbook of Work Physiology, fourth edition, Human Kinetics, Champaign, IL, 2003.
  • Bhattacharya, A. & McGlothlin, J.D. (eds.), Occupational ergonomics: theory and applications, CRC Press, 2011.
  • Bridger, R.S., Introduction to Ergonomics, third edition, CRC Press, Boca Raton, FL, 2008.
  • Chaffin, D.B., Andersson, G.B.J. & Martin, B.J., Occupational Biomechanics, fourth edition, John Wiley & Sons, Hoboken, NJ, 2006.
  • Chengalur, S.N., Rodgers, S.H. & Bernard, T.E. (eds.), Kodak's Ergonomic Design for People at Work, second edition, John Wiley & Sons, Hoboken, NJ, 2004.
  • Dul, J. & Weerdmeester, B., Ergonomics for Beginners: A Quick Reference Guide, third edition, CRC Press, Boca Raton, FL, 2008.
  • Karwowski, W., Szopa, A., Soares, M. (eds.), Handbook of Standards and Guidelines in Ergonomics and Human Factors, CRC Press, 2021.
  • Kroemer, K.H.E., "Extra-Ordinary" Ergonomics. How to Accommodate Small and Big Persons, the Disabled and Elderly, Expectant Mothers and Children, HFES Issues in Human Factors and Ergonomics Series, Volume 4, CRC Press, Boca Raton, FL, 2006.
  • Kroemer, K.H.E. & Grandjean, E., Fitting the task to the human: a textbook of occupational ergonomics, fifth edition, Taylor & Francis, London, 1997.
  • MacLeod, D., The Ergonomics Edge: Improving Safety, Quality and Productivity, Van Nostrand Reinhold, New York, 1995.
  • Marras, W.S. & Karwowski, W. (eds.), The Occupational Ergonomics Handbook, second edition, CRC Press, Boca Raton, FL, 2008, 2 volumes.
  • National Research Council & Institute of Medicine. Musculoskeletal Disorders and the Workplace. Low Back and Upper Extremities, National Academy Press, Washington DC, 2001.
  • Oborne, D.J., Ergonomics at Work, third edition, John Wiley & Sons, Chichester, 1995.
  • Pheasant, S., Ergonomics, Work and Health, Macmillan, Basingstoke, Hants, 1991.
  • Pheasant, S. & Haslegrave, C.M., Bodyspace: Anthropometry, Ergonomics and the Design of Work. Taylor & Francis, London, third edition, 2006.
  • Salvendy, G., Karwowski, W. (eds.), Handbook of Human Factors and Ergonomics, fourth edition, John Wiley & Sons, New York, 2021.
  • St John Holt, A. & Allen, J., Principles of health and safety at work, eighth edition, IOSH Publishing, Wigston, Leicestershire, 2009.
  • Tillman, B., Human Factors and Ergonomics Design Handbook, 2016.
  • Wilson, J.R. & Sharples, S., Evaluation of Human Work, fourth edition, CRC Press, Boca Raton, FL, 2015.

Ergonomics / Human factors scientific journals

  • Applied Ergonomics, ISSN 0003-6870 [57]
  • Behaviour and Information Technology, ISSN 0144-929X (Print), 1362-3001 (Online) [58]
  • Ergonomics, ISSN 0014-0139 (Print), 1366-5847 (Online) [59]
  • Ergonomics in Design, ISSN 1064-8046 [60]
  • Human Factors, ISSN 0018-7208 (Print), 1547-8181 (Online) [61]
  • Human Factors and Ergonomics in Manufacturing & Service Industries, ISSN 1090-8471 (Print), 1520-6564 (Online) [62]/(ISSN)1520-6564
  • International Journal of Industrial Ergonomics, ISSN 0169-8141 [63]
  • Safety and Ergonomics, ISSN 1080-3548 (Print), 2376-9130 (Online) [64]
  • Theoretical Issues in Ergonomics Science, ISSN 1463-922X (Print), 1464-536X (Online) [65]

OSH scientific journals

  • American Journal of Industrial Medicine, ISSN 0271-3586 (Print), 1097-0274 (Online) [66]
  • Annals of Work Exposures and Health, ISSN 0003-4878 (Print), 1475-3162 (Online) [67]
  • Archives of Environmental and Occupational Health, ISSN 1933-8244 [68]
  • Indian Journal of Occupational and Environmental Medicine, ISSN 0973-2284 (Print), 1998-3670 (Online) [69]
  • Industrial Health, ISSN: 0019-8366 (Print), 1880-8026 (Online) [70]
  • International Archives of Occupational and Environmental Health, ISSN: 0340-0131 (Print), 1432-1246 (Online) [71]
  • Journal of Occupational and Environmental Hygiene, ISSN 1545-9624 (Print), 1545-9632 (Online) [72]
  • Journal of Occupational and Environmental Medicine, ISSN 1076-2752 (Print), 1536-5948 (Online) [73]
  • Occupational and Environmental Medicine, ISSN 1351-0711 (Print), 1470-7926 (Online) [74]
  • Occupational Medicine, ISSN 0962-7480 (Print), 1471-8405 (Online) [75]
  • Safety Science, ISSN 0925-7535 [76]
  • Scandinavian Journal of Work, Environment and Health, ISSN 0355-3140 (Print), 1795-990X (Online) [77]

References

  1. 1.0 1.1 1.2 1.3 1.4 1.5 1.6 IEA - International Ergonomics Association. What is Ergonomics? Available at: [1]
  2. ISO 6385: Ergonomic principles in the design of work systems. Available at: [2]
  3. ISO 26800: Ergonomics -- General approach, principles and concepts. Available at: [3]
  4. Odholm, O.G. & Murrell, K.F.H., ‘The Ergonomics Research Society - A History 1949-1970’, 1973, pp. 7-8.
  5. Towarzystwa Ziemi Nidzickiej (2004). Biography of Wojciech Jastrzebowski [in Polish].
  6. McCormick, E.J. & Sanders, M.S., Human Factors in Engineering and Design, fifth edition, McGraw Hill, New York, 1983
  7. IEA, Core competencies in human factors and ergonomics (HFE). Professional knowledge and skills. Available at: [4]
  8. ISO 12100: Safety of machinery -- General principles for design -- Risk assessment and risk reduction. Available at: [5]
  9. ISO/TR 22100-3: Safety of machinery -- Relationship with ISO 12100 -- Part 3: Implementation of ergonomic principles in safety standards. Available at: [6]
  10. Council Directive 89/391/EEC on the introduction of measures to encourage improvements in the safety and health of workers at work. Available at: [7]
  11. 11.0 11.1 Council Directive 89/654/EEC concerning the minimum safety and health requirements for the workplace. Available at: [8]
  12. 12.0 12.1 Council Directive 89/655/EEC on the minimum safety and health requirements for the use of work equipment by workers at work. Available at: [9]
  13. 13.0 13.1 Council Directive 89/656/EEC on the minimum health and safety requirements for the use by workers of personal protective equipment at the workplace. [10]
  14. 14.0 14.1 Council Directive 90/269/EEC on the minimum health and safety requirements for the manual handling of loads where there is a risk particularly of back injury to workers. Available at: [11]
  15. 15.0 15.1 Council Directive 90/270/EEC on the minimum safety and health requirements for work with display screen equipment. Available at: [12]
  16. Council Directive 91/383/EEC supplementing the measures to encourage improvements in the safety and health at work of workers with a fixed-duration employment relationship or a temporary employment relationship. Available at: [13]
  17. Pheasant, S. & Haslegrave, C.M., Bodyspace: Anthropometry, Ergonomics and the Design of Work, 3rd edition, Taylor & Francis, London, 2006.
  18. Chengalur, S.N., Rodgers, S.H., & Bernard, T.E. (eds.), Kodak's Ergonomic Design for People at Work., second edition, John Wiley & Sons, Hoboken, NJ, 2004, p. 411.
  19. EU OSHA – European Agency for Safety and Health at Work (no date). Musculoskeletal disorders. Retrieved 30 January 2013, from: [14]
  20. Astrand, P.O., Rodahl, K., Dahl, K. A. & Strømme, S.B., Textbook of Work Physiology, fourth edition, Human Kinetics, Champaign, IL, 2003.
  21. EU OSHA - European Agency for Safety and Health at Work, Literature review - The human-machine interface as an emerging risk, 2009. Available at: [15]
  22. EU-OSHA, Impact of artificial intelligence on occupational safety and health, 2021. Available at: [16]
  23. Petrat, D. Artificial intelligence in human factors and ergonomics: an overview of the current state of research. Discover Artificial Intelligence, 3 (2021). Available at: [17]
  24. HSE – Health and Safety Executive (no date). Human factors: Managing human failures. Retrieved 30 January 2013, from: [18]
  25. BAuA – Bundesanstalt für Arbeitsschutz und Arbeitsmedizin, The ups and downs of sitting - Sitting at work and elsewhere, BAuA, Dortmund, Germany, 2008. Available at: [19]
  26. BAuA – Bundesanstalt für Arbeitsschutz und Arbeitsmedizin, Up and down, up and down - How dynamic sitting and standing can improve health in the office, BAuA, Dortmund, Germany, 2008, Available at: [20]
  27. Pheasant, S., Ergonomics, Work and Health. Macmillan, Basingstoke, Hants, 1991.
  28. EU OSHA - European Agency for Safety and Health at Work (no date). Efact 13 Office Ergonomics. Available at: [21]
  29. Haines, H. & Wilson, J.R., ‘Development of a framework for participatory ergonomics’, Contract Research Report 174/1998, HSE Books, Sudbury, Suffolk, 1998. Available at: [22]
  30. Morris, W., Wilson, J. & Koukoulaki, T., Developing a participatory approach to the design of work equipment: Assimilating lessons from workers’ experience, ETUI, Brussels, 2004. Available at: [23]
  31. EU-OSHA, Participatory ergonomics and preventing musculoskeletal disorders in the workplace, 2021. Available at: [24]
  32. Habib, R.R. & Messing, K., ‘Gender, women's work and ergonomics’, Ergonomics, Vol. 55, Iss 2, 2012, pp. 129-132. Available at: [25]
  33. Council Directive 2000/78/EC of 27 November 2000 (OJ No L 303, 02/12/2000, pp. 16 - 22) establishing a general framework for equal treatment in employment and occupation. Available at: [26]
  34. IEA - International Ergonomics Association. Networks. [27]


Links for further reading

EU-OSHA - European Agency for Safety and Health at Work, Practical tools and guidance on musculoskeletal disorders, Available at: [78]

EU-OSHA - European Agency for Safety and Health at Work, Healthy workers, thriving companies - a practical guide to wellbeing at work, Available at: [79]

EU-OSHA - European Agency for Safety and Health at Work, The human-machine interface as an emerging risk, Available at: [80]

EU-OSHA - European Agency for Safety and Health at Work, Worker participation in the prevention of musculoskeletal risks at work. Available at: [81]

ILO - International Labour Organisation, Ergonomic checkpoints: Practical and easy-to-implement solutions for improving safety, health and working conditions. Available at: [82]