ISO Standards of Usability: the Parts That Are Interesting to UX Designers
I came across “The Ergonomics of Human System Interaction” while writing my book on Product Design. These parts of ISO 9241 are interesting to UX designers.
ISO 9241 was originally written in 1996 to cover the ergonomic needs for office work with displays. Several refreshes have been published after.
It is interesting because of its large amount of information on usability. A term we wore out in its use with mobile application design. Expect the standards to cover the usability of hardware, software and processes alike.
Getting copies of the standards are expensive. However, a local library would be able to make them available for free. Universities might have a copy of the standards available as well.
Surprisingly, several European countries have adopted some of these standards in their national law.
What's in it for UX Designers?
Few people would be interested in all of the ISO 9241. So, I went in and compiled the parts that might interest UX designers.
Part 11: Usability: Definitions and concepts
Gives a framework for understanding the concept of usability. And, applying it to situations where people use interactive systems and services.
Part 100: Introduction to standards related to software ergonomics
Gives a brief overview of the content of the standards. Additionally, what the relationship is between several standards and helps understand several definitions of Usability.
Part 110: Dialogue principles
Presents usability questions that apply to dialogues. It presents the seven principles of these dialogues:
- The dialogue should be suitable for the task.
- Self-descriptiveness: the dialogue should make clear what the user should do next.
- Controllability: the user should be able to control the pace and sequence of the interaction.
- Conformity with user expectations: it should be consistent, also with other established interactions.
- Error tolerance: the dialogue should be forgiving.
- Suitability for individualisation: the dialogue should be able to be customised to suit the user.
- Suitability for learning. The dialogue should support learning.
Part 112: Principles for the presentation of information
Gives design principles related to the presentation of information. It helps us design interfaces that improve the understanding of information (either visual, auditory, or tactile). It is focused on helping the user complete a task.
Part 125: Guidance on the visual presentation of information
Guides the reader through a visual design process and the basis of an evaluation. And, gives pointers on the organisation of information.
Part 129: Guidance on software individualisation
This part provides guidance on how the various aspects of individualisation are made usable and accessible, but also where it might be appropriate or inappropriate.
Part 151: Guidance on World Wide Web user interfaces
Gives guidance on the human-centred design of web user interfaces with the aim of increasing usability. All, with the focus on design strategy, content design, navigation and search; and content presentation. One of the more interesting ones.
Part 143: Forms
Gives requirements and recommendations for the design of forms (e.g. contact forms or payment forms). Not only online ones.
Part 161: Guidance on visual user interface elements
This part describes visual user-interface elements (e.g. buttons) presented by software and when and how to use them. It includes a list of generic visual user-interface elements, as well.
Part 171: Guidance on software accessibility
Part 171 covers issues associated with designing for people with physical, sensory and cognitive disabilities, including those who are temporarily disabled, and the elderly.
Part 210: Human-centred design for interactive systems
Provides requirements and recommendations for human-centred design principles throughout the iterations of interactive systems.
Important to know
It is important not to confuse standards with best practices. For each product, the standard might vary from the most optimal solution. It is always recommended doing user tests to find the solution that fits the specific problem.
Does your country have them in their law?