Intro

In the dusty institutions where usability standards gather to party with each other, ISO 9241 is a bit of a celebrity. It is widely cited by people who would be hard pushed to name any other standard, and parts of it are virtually enshrined in law in some European countries (such as the UK). But as is the fate of many celebrities, all most usability professionals know about the standard is its name: “Ergonomic requirements for office work with visual display terminals (VDTs)”. Ah, VDTs: as evocative of the eighties as yuppies and punk rock music. This makes the standard seem out of date, but don’t be fooled. ISO have renamed it: as the parts are re-issued they will adopt the much sexier title, “Ergonomics of Human System Interaction”.

It is a shame that ISO 9241 is more widely cited than read because it includes a wealth of information that covers every aspect of usability, including hardware, software and usability processes. You could use the standard to design a workstation, evaluate a display, set usability metrics, evaluate a graphical user interface, test out a new keyboard, assess a novel interaction device such as a joystick, check that the working environment is up to scratch, and measure reflections and colour on a display screen. It contains checklists to help structure a usability evaluation, examples of how to operationalise and measure usability, and extensive bibliographies. It even has the courage to define usability!

There are a few reasons why it is not widely read.

Standards are not easy to get hold of.  You can’t get them in bookshops or find them on the high street (although you can now order them online through ISO).

• ISO 9241 is expensive. If you purchase all of the parts from ISO’s web site it will cost SFr.1,820 (about £837, €1183 or $1329; see what it costs). Standards are big business.
• The use of the phrase “office work” in the title of all of the parts of ISO 9241 makes it sound like the standard is relevant only for, well, office work. In practice, many of the parts are relevant to a wide range of applications. A good example is part 17 (Form Filling dialogues). Although this part was conceived before web sites were common, it contains a lot of guidance that web designers would do well to follow.
• Standards have a reputation for being inaccessible, either because the language is legalistic or because they are written in a peculiar dialect of English that is favoured by people for whom English is not their first language.
• ISO 9241 is big. If you pile all of the original seventeen parts on top of each other it measures over two inches in thickness. This is about as thick as the hardback versions of Nielsen’s Usability Engineering and Shneiderman’s Designing the User Interface combined. (And ISO 9241 is softback and printed on A4 paper).

The truth is that few people would be interested in all of the parts of ISO 9241, which is why indeed it has been published as
separate documents (with over 50 more in the wings).  But it is hard to work out which particular part you are interested in just from the title, and that is about all the information that is publicly available.  Also, although you may be interested only in a few of the parts, it’s always nice to get an overview and see what you are missing in the other parts.  You might choose the standard credit card over the platinum version, but you still like to know about the extras you have forfeited.

We hope this document comes to your rescue.  View it as your Michelin travel guide to the various destinations of ISO 9241. If nothing else, it will help you bluff your way through a meeting.

Who is ISO?

ISO stands for the International Organisation for Standardisation and is a network of national standards institutes from 147 countries. Because technology is an international business, manufacturers pay attention to international standards. Many countries (especially those in Europe) also adopt ISO standards as national standards, and so you may find parts of ISO 9241 cited as the route to compliance with health and safety legislation.

More information about ISO.

Other usability standards

ISO 9241 is just one of many standards that apply to usability and ergonomics.  Other relevant ISO usability standards:

• ISO 6385:1981 Ergonomic principles in the design of work systems
• ISO 10075:1991 Ergonomic principles related to mental work-load -- General terms and definitions
• ISO 10075-2:1996 Ergonomic principles related to mental workload -- Part 2: Design principles