ISO standards

Standards in usability and user-centred design

This document sets out the key international standards in the area of usability and user-centred design. The main body of standards in this area are those produced by ISO (the International Standards Organisation), to which individual national standards organisations have input. Most are also adopted as European (CEN) standards. Copies can be obtained from ISO or from national standards bodies.

In addition to standards, there are a large number of guidelines that have been published by individuals and organisations around the world. If designing a particular type of product (e.g. a piece of PC software) it can be worth consulting guidelines specific to that type of product (e.g. Interface design guidelines for Microsoft Windows, or the Apple Desktop). There are also guidelines that provide recommendations concerning accessibility of different types of products and systems for users with disabilities.

Usability and user-centred design standards can be divided up into 3 main categories:

  1. Product usage characteristics (how well users perform with it, how satisfied they are with it)
  2. Product interface attributes (design of the interface and interaction)
  3. Development process (activities carried out during product development)

Some standards (for example, those relating to software in ISO 9241) set out few mandatory requirements but instead set out guidelines and conditional requirements. When using such standards it is particularly important to have a good understanding of the product's context of use, user characteristics, user tasks, user requirements, and so on.

1. Standards dealing with product usage characteristics

ISO 9241-11 (1998) Guidance on Usability

A central standard in usability, explaining how to identify the information that it is necessary to take into account when specifying or evaluating usability in terms of measures of user performance and satisfaction. Guidance is given on how to describe the context of use of the product (hardware, software or service) and required measures of usability. It includes an explanation of how the usability of a product can be specified and evaluated as part of a quality system (e.g. one conforming to ISO 9001).

ISO 9241-11 defines usability as:

"The extent to which a product can be used by specified users to achieve specified goals with effectiveness, efficiency and satisfaction in a specified context of use."

Other relevant standards:
  • ISO/IEC 25010 (2011) Systems and software engineering - Systems and software Quality Requirements and Evaluation (SQuaRE) - System and software quality model

2. Standards dealing with product interface attributes

These standards deal with characteristics of the product itself and can be used to specify and evaluate details of the user interface of the product and how it works. However, it is important to note that they must be interpreted and applied based on the context of use of the particular product in question.

ISO 9241-1 (1997) Ergonomic requirements for office work with visual display terminals (VDTs) - General Introduction
This part introduces the multi-part standard ISO 9241 for the ergonomic requirements for the use of visual display terminals for office tasks and explains some of the basic underlying principles. It provides some guidance on how to use the standard and describes how conformance to parts of ISO 9241 should be reported.

ISO 9241-2 (1992) Guidance on task requirements
This part deals with the design of tasks and jobs involving work with visual display terminals. It provides guidance on how task requirements may be identified and specified within individual organisations and how task requirements can be incorporated into the system design and implementation process.

ISO 9241-1xx series - Software ergonomics
These parts concern different aspects of interactive systems that affect usability and apply to application software (including web-based applications), operating systems, embedded software, software development tools and assistive technologies.
  • Part 100: Introduction to standards related to software ergonomics
  • Part 110: Dialogue principles
  • Part 112: Principles for the presentation of information
  • Part 125: Guidance on visual presentation of information
  • Part 129: Guidance on software individualization
  • Part 143: Forms
  • Part 151: Guidance on World Wide Web user interfaces
  • Part 154: Interactive voice response (IVR) applications
  • Part 161: Guidance on visual user interface elements
  • Part 171: Guidance on software accessibility

(The earlier ISO 9241-10 Dialogue Principles, ISO 9241-12 Presentation of information and ISO 9241-17 Form-filling dialogues have been superseded by parts in the above 9241-1xx series.)

ISO 9241-3xx series - Electronic visual displays and related hardware
These parts specify the ergonomics requirements for display screens which ensure that they can be read comfortably, safely and efficiently to perform office tasks. Although it deals specifically with displays used in offices, it is appropriate to specify it for most applications that require general purpose displays to be used in an office-like environment.
  • Part 300: Introduction to electronic visual display requirements
  • Part 302: Terminology for electronic visual displays
  • Part 303: Requirements for electronic visual displays
  • Part 304: User performance test methods for electronic visual displays
  • Part 305: Optical laboratory test methods for electronic visual displays
  • Part 306: Field assessment methods for electronic visual displays
  • Part 307: Analysis and compliance test methods for electronic visual displays
  • Part 308: Surface-conduction electron-emitter displays (SED)
  • Part 309 (TR): Organic light-emitting diode (OLED) displays

(The earlier ISO 9241-3 Visual display requirements, ISO 9241-7 Display requirements with reflections, ISO 9241-8 Requirements for displayed colours and ISO 13406 Requirements for visual displays based on flat panels have all been superseded by parts in the above 9241-3xx series.)

ISO 9241-4xx series – Physical input devices
These parts specify ergonomics principles and design guidance for the following input devices: keyboards, mice, pucks, joysticks, trackballs, trackpads, tablets and overlays, touch sensitive screens, styli, light pens, voice controlled devices, and gesture controlled devices. (Keyboard layouts are dealt with separately in various parts of ISO/IEC 9995: 1994 Information Processing - Keyboard Layouts for Text and Office Systems).
  • Part 400: Principles and requirements for physical input devices
  • Part 410: Design criteria for physical input devices
  • Part 411 (TS): Evaluation methods for the design of physical input devices

(The earlier ISO 9241-4 Keyboard requirements and ISO 9241-9 Requirements for non-keyboard input devices have been superseded by parts in the above 9241-4xx series.)

ISO 9241-5 (1998) - Workstation layout and postural requirements
This part specifies the ergonomics requirements for a Visual Display Terminal workplace which will allow the user to adopt a comfortable and efficient posture.

(This part will in the future be superseded by parts in the 9241-5xx series.)

ISO 9241-6 (1999) - Environmental requirements
This part specifies the ergonomics requirements for the Visual Display Terminal working environment which will provide the user with comfortable, safe and productive working conditions.

(This part will in the future be superseded by parts in the 9241-5xx series.)

ISO 9241-9xx series – Tactile and haptic interactions
These parts specify ergonomic principles and design guidance for tactile and haptic hardware and software interactions.
  • Part 910: Framework for tactile and haptic interaction
  • Part 920: Guidance on tactile and haptic interactions

(The earlier ISO 9241-4 Keyboard requirements and ISO 9241-9 Requirements for non-keyboard input devices have been superseded by parts in the above 9241-4xx series.)

ISO 9241-13 (1998) - User guidance
This part provides recommendations for the design and evaluation of user guidance attributes of software user interfaces including Prompts, Feedback, Status, On-line Help and Error Management.

ISO 9241-14 (1997) - Menu dialogues
This part provides recommendations for the ergonomic design of menus used in user-computer dialogues. The recommendations cover menu structure, navigation, option selection and execution, and menu presentation (by various techniques including windowing, panels, buttons, fields, etc.).

ISO 9241-15 (1998) - Command language dialogues (WITHDRAWN)

This part provides recommendations for the ergonomic design of command languages used in user-computer dialogues. The recommendations cover command language structure and syntax, command representations, input and output considerations, and feedback and help.

ISO 9241-16 (1999) - Direct manipulation dialogues (WITHDRAWN)

This part provides recommendations for the ergonomic design of direct manipulation dialogues, and includes the manipulation of objects, and the design of metaphors, objects and attributes. It covers those aspects of Graphical User Interfaces that are directly manipulated, and not covered by other parts of ISO 9241.

ISO 9241-151 (2008) - Guidance on World Wide Web user interfaces (WITHDRAWN)

Provides a large number of specific principles for designing web site interfaces. These are divded up into: high-level design decisions and design strategy, content design, navigation, and content presentation.

ISO 9241-171 (2008) - Guidance on software accessibility
Provides guidance on achieving a high level of accessibility in software user interfaces at work, in the home, in education and in public places. It covers issues for people with a broad range of physical, sensory and cognitive abilities, as well as the elderly and those with temporary disabilities.

(The earlier ISO TS 16071 Guidance on accessibility of human-computer interfaces has been superseded by ISO 9241-171)

Other relevant standards:
  • ISO 6385 Ergonomic principles in the design of work systems
  • ISO 11064 Ergonomic design of control centres
  • ISO 14915 Multimedia user interface design - Software ergonomic requirements
  • ISO 20282 Ease of operation of everyday products
  • ISO/IEC 10741-1 Dialogue interaction - Cursor control for text editing
  • ISO/IEC 11581 Icon symbols and functions
  • ISO/IEC 15910 Software user documentation process
  • ISO/IEC 25062 Common Industry Format (CIF) for usability test reports
  • ISO/IEC 62366 Application of usability engineering to medical devices

3. Standards dealing with the product development process

ISO 9241-210 (2010) Human-centred design for interactive systems [previously ISO 13407 (1999)]
This standard provides guidance on human-centred design activities throughout the development life cycle of interactive computer-based systems. It is a tool for those managing design processes and provides guidance on sources of information and standards relevant to the human-centred approach.

Human-centred design is described as a multidisciplinary activity, incorporating human factors and ergonomics knowledge and techniques with the objective of enhancing effectiveness and efficiency, improving human working conditions, and counteracting possible adverse effects of use on human health, safety and performance.

There are four essential user-centred design activities which should be planned for and undertaken in order to incorporate usability requirements into the development process. These are:
  • understand and specify the context of use
  • specify the user requirements
  • produce design solutions to meet user requirements
  • evaluate the designs against requirements

The activities are carried out in an iterative fashion, with the cycle being repeated until the particular usability objectives have been attained. The plan should identify how these activities can be integrated with other development activities, as well as people responsible for them.

Understand and specify the context of use
This should address the following important aspects:
  • the characteristics of the intended users
  • the tasks the users will perform
  • the environment in which users will use the system
Specify the user requirements
This looks at user and organisational requirements in relation to the context of use description (1), and it should:
  • Identify the range of relevant users and other personnel in the design
  • Provide a clear statement of the human-centred design goals
  • Set appropriate priorities for the different requirements
  • Provide measurable benchmarks against which emerging designs can be tested
  • Be confirmed by the users or those representing their interests in the process
  • Include and statutory or legislative requirements
  • Be adequately documented
Produce design solutions
This consists of the following:
  • Develop outline design proposals with multi-disciplinary input
  • Make the design solution(s) more concrete using simulations, mock-ups, etc.
  • Show the design solution(s) to users and allow them to perform/simulate tasks
  • Iterate the process until design objectives are met
Evaluate designs against requirements
This is an essential step which assesses whether user and organisational objectives have been met and provides feedback which can be used to improve design. There are a variety of evaluation methods, varying in their formality, rigour and user involvement - the best method(s) will depend on the nature of the product being developed, finances, and time constraints.

ISO 9241-220 (2019) Ergonomics of human-system interaction – Processes for enabling, executing and assessing human-centred design within organisations
This standard describes processes that represent good practice for human-centred design and builds on ISO 9241-210 setting out process models to provide:
  • the potential to analyse the ability of an organization to deliver and/or maintain a system that meets a required level of performance and quality;
  • a description of the factors that hinder this ability; and
  • a means of addressing such shortcomings and mitigating associated risks of adverse consequences.
This document can be used to:
  • implement human-centred design as part of a system development or procurement process and/or support life cycle;
  • assess an enterprise’s existing capability to carry out the human-centred processes;
  • improve the application of human-centred design as part of an existing system development process;
  • develop competence in human-centred design.

A related standard, ISO/TS 18152:2010, has a broader scope and presents a human-systems (HS) model for use in ISO/IEC 15504-conformant assessment of the maturity of an organization in performing the processes that make a system usable, healthy and safe. It describes processes that address human-system issues and the outcomes of these processes. It details the practices and work products associated with achieving the outcomes of each process.

(The earlier ISO ISO TR 18529 Human-centred lifecycle process descriptions has been superseded by ISO 9241-220.)