Mental stress? - new ISO Standard helps optimise mental workload at the office

Issue 50 – June 2013

This article was first published in ISO Focus+, April 2013, and is summarised here with permission.

Mental load at work? Does your job demand continued attention like, for instance, air traffic controllers and bus drivers? Are light conditions essential for your work, such as when checking coated surfaces in the automobile industry or the quality of glass bottles in the soft drink industry? Or do wider societal concerns like an economic crisis impact on your performance?

Any activity can generate mental stress. The resulting strain and fatigue can affect individuals and in turn indirectly have a wider impact on the organisation. As a result, ISO has developed a three-part Standard, ISO 10075, Ergonomic principles related to mental workload, to help employees, employers, their representatives, system supervisors, designers, authorities, and other practitioners address issues of mental workload in the design of work systems.

The Standard proposes a three-pronged approach.

  1. Part 1, General terms and definitions, defines a common terminology to help users to understand the subject. The Standard is based on a simple 'stimulus-organism-response' model and discriminates between the mental-stress impacts from outside the individual (stimuli), and the mental-strain response from within (individual). This document is relevant to employers and trade unions when negotiating agreements on mental workload, whether they are looking at working conditions or their impact on the individual.
  2. Part 2, Design principles, describes the basic design precepts necessary to avoid impairing effects and to improve working conditions. It focuses on tasks, equipment, environment, and organisation, with a view to optimising, rather than minimising, mental workload, that is, avoiding the extremes of a workload that is either too heavy or too light. This document is particularly relevant for designers of work systems and equipment, managers, workers' representatives, and health and safety authorities.
  3. Part 3, Principles and requirements concerning methods for measuring and assessing mental workload, focuses on assessment tools. Since there is no single best way of assessing mental stress or strain, the Standard does not recommend specific measurement instruments, but instead outlines requirements for their objectivity, reliability, validity, sensitivity, and diagnosticity. There are a large number of measurement instruments available, each designed for different situations and purposes.
    • This document will help practitioners choose adequate instruments and give guidance for developers of measurement procedures. It is intended for use mainly by ergonomic experts, such as psychologists, occupational health specialists, and/or physiologists, with appropriate theoretical and practical training in the use and interpretation of such methods. But it also provides non-experts, for example, employers, employees, and their representatives, system managers, and designers, and public authorities, with useful information to orient their assessment and measurement of mental workload.

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Summarised from ISO Focus+, April 2013.


Published in business and ICT.