4.1 Ergonomics is the field concerned with designing physical spaces or workstations, equipment, tools, processes, procedures, and systems to accommodate the capabilities and limitations of human users. Pain, fatigue, or injuries may arise if there is a mismatch between the person’s abilities and the demands or requirements of the activity or task, the environment, or the tools/equipment. The types of injuries that can occur are caused by exposure to chronic conditions rather than acute hazards and usually develop over time from the accumulated trauma of repeated stress to the body. These injuries are commonly known as MSDs (musculoskeletal disorders), also called CTDs (cumulative trauma disorders).

4.2 Although MSDs are most commonly associated with physical risk factors, they can also be affected by non-physical stressors. Organizational factors can affect cognitive demands on workers, or the social environment can create psychosocial stress. These may, in turn, generate a physiological response such as increased muscle tension beyond what would normally be needed for the task or activity. Therefore, organizational factors and the social environment may also need to be considered when assessing the risk factors of a task or activity. However, these factors are outside the scope of this guide and are only mentioned here to provide a greater understanding of the multifactorial nature of MSD causation.

4.3 Human factors engineering/ergonomics can provide guidelines for implementing exoskeletons safely in the workplace. These guidelines can help prevent discomfort, pain, or injury to the exoskeleton user, make the task easier to complete, or reduce the risk for errors. Ergonomics can help to assess how well the exoskeleton works for the user and the work environment, and how well it supports the activities of interest. This includes not only job functions, but also interactions with other people and other pieces of equipment in the work area, and with physical and environmental factors that could change how the exoskeleton functions or performs. Any of these factors may affect the safe and successful implementation of the exoskeleton.

1.1 This guide covers ergonomic guidelines for evaluating and understanding the risk factors that could lead to cumulative harm to the exoskeleton user.

1.2 This guide is intended for implementers in organizations that utilize exoskeletons for worker safety. The reader of this guide is assumed to have a basic knowledge of the concepts and principles of human factors engineering and ergonomics.

Note 1: Implementer is defined as a natural or legal person responsible for purchase, administration and/or implementation of exoskeletons in task-specific environments.

1.3 Exoskeletons are often used with the expectation that they may reduce the risk of pain, fatigue, or work-related musculoskeletal injuries. However, the use of an exoskeleton should not exacerbate existing risk factors for these types of issues, nor should it introduce new, unmitigated risk factors. This may include risk factors that arise when performing activities with the exoskeleton that differ from the risk factors that exist when the exoskeleton is not used.

1.4 This guide briefly describes ergonomic risk factors and explains why they are of concern, with special emphasis on how exoskeletons may increase or decrease these risk factors. The risk factors are:

1.4.1 Excessive force,

1.4.2 Awkward (or non-neutral) postures,

1.4.3 Repetitive motions,

1.4.4 Contact pressure,

1.4.5 Vibration, and

1.4.6 Environmental stressors (heat, cold).

1.5 The risk factors may come from elements within the workplace or area of use, environmental factors, the task or activity being performed, the tools or equipment being used, the exoskeleton itself, or interactions between any of these.

1.6 General safety concerns related to injuries such as fractures, pinch points, electrocution, and so forth are outside the scope of this guide; the reader is referred to Guide F3527. Although this guide discusses the need for ergonomic evaluations, it is outside the scope of this guide to provide instructions on how to do so. Please refer to Handbook of Human Factors and Ergonomics; Kodak’s Ergonomic Design for People at Work; Elements of Ergonomics Programs; or other ergonomic textbooks for guidance on performing ergonomic evaluations.2-4

1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.

1.8 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.