ergonomics user interface standards: are they more trouble than they are worth?

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This article was downloaded by: [Linnaeus University] On: 05 October 2014, At: 20:48 Publisher: Taylor & Francis Informa Ltd Registered in England and Wales Registered Number: 1072954 Registered office: Mortimer House, 37-41 Mortimer Street, London W1T 3JH, UK Ergonomics Publication details, including instructions for authors and subscription information: http://www.tandfonline.com/loi/terg20 Ergonomics user interface standards: are they more trouble than they are worth? Tom Stewart a a System Concepts Limited Published online: 10 Nov 2010. To cite this article: Tom Stewart (2000) Ergonomics user interface standards: are they more trouble than they are worth?, Ergonomics, 43:7, 1030-1044, DOI: 10.1080/001401300409206 To link to this article: http://dx.doi.org/10.1080/001401300409206 PLEASE SCROLL DOWN FOR ARTICLE Taylor & Francis makes every effort to ensure the accuracy of all the information (the “Content”) contained in the publications on our platform. However, Taylor & Francis, our agents, and our licensors make no representations or warranties whatsoever as to the accuracy, completeness, or suitability for any purpose of the Content. Any opinions and views expressed in this publication are the opinions and views of the authors, and are not the views of or endorsed by Taylor & Francis. The accuracy of the Content should not be relied upon and should be independently verified with primary sources of information. Taylor and Francis shall not be liable for any losses, actions, claims, proceedings, demands, costs, expenses, damages, and other liabilities whatsoever or howsoever caused arising directly or indirectly in connection with, in relation to or arising out of the use of the Content. This article may be used for research, teaching, and private study purposes. Any substantial or systematic reproduction, redistribution,

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Page 1: Ergonomics user interface standards: are they more trouble than they are worth?

This article was downloaded by: [Linnaeus University]On: 05 October 2014, At: 20:48Publisher: Taylor & FrancisInforma Ltd Registered in England and Wales Registered Number:1072954 Registered office: Mortimer House, 37-41 Mortimer Street,London W1T 3JH, UK

ErgonomicsPublication details, including instructions forauthors and subscription information:http://www.tandfonline.com/loi/terg20

Ergonomics user interfacestandards: are they moretrouble than they areworth?Tom Stewart aa System Concepts LimitedPublished online: 10 Nov 2010.

To cite this article: Tom Stewart (2000) Ergonomics user interface standards:are they more trouble than they are worth?, Ergonomics, 43:7, 1030-1044, DOI:10.1080/001401300409206

To link to this article: http://dx.doi.org/10.1080/001401300409206

PLEASE SCROLL DOWN FOR ARTICLE

Taylor & Francis makes every effort to ensure the accuracy of allthe information (the “Content”) contained in the publications on ourplatform. However, Taylor & Francis, our agents, and our licensorsmake no representations or warranties whatsoever as to the accuracy,completeness, or suitability for any purpose of the Content. Anyopinions and views expressed in this publication are the opinions andviews of the authors, and are not the views of or endorsed by Taylor& Francis. The accuracy of the Content should not be relied upon andshould be independently verified with primary sources of information.Taylor and Francis shall not be liable for any losses, actions, claims,proceedings, demands, costs, expenses, damages, and other liabilitieswhatsoever or howsoever caused arising directly or indirectly inconnection with, in relation to or arising out of the use of the Content.

This article may be used for research, teaching, and private studypurposes. Any substantial or systematic reproduction, redistribution,

Page 2: Ergonomics user interface standards: are they more trouble than they are worth?

reselling, loan, sub-licensing, systematic supply, or distribution in anyform to anyone is expressly forbidden. Terms & Conditions of accessand use can be found at http://www.tandfonline.com/page/terms-and-conditions

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Ergonomics user interface standards: are they more troublethan they are worth?

TOM STEWART*

System Concepts Limited, 2 Savoy Court, Strand, London WC2R 0EZ, UK

Keywords: User interface; Standards; ISO; VDT; Usability.

The purpose of this paper is to review the history, progress and results of one areaof international standardizationÐ the ergonomics of human-system interaction. Itis a personal perspective based on my experiences as Chairman of ISO/TC159/SC4 over the past 17 years. The paper starts with some historical background andsummarizes the main work of the Committee. It then identi® es ® ve areas wherethe results of the standardization work could have been more successful anddiscusses what went wrong. These problems include the long time-scale fordevelopment, how the standards were misunderstood, how political the processcan be, how we may have tried to be too clever and how the abundance of help attimes may have been a problem. The paper concludes with an explanation of whythe activity and the results were not all bad. The ® ve positive areas include thebene® ts that can come from the slow pace of the work, the bene® ts of structureand formality, why standards do not have to be restrictive, how the standardsthemselves are only part of the outcome and how being a truly internationalexperience makes it all worthwhile.

1. Introduction

The purpose of this paper is to review the history, progress and results of one area of

international standardizationÐ the ergonomics of human-system interactionÐ overthe past 17 years. Although I will attempt to put the case for and the case against

standards, it would be foolish for me to suggest that this will be an impartial review.

I would not have spent and continue to spend a signi® cant portion of my working

life developing standards if I were not basically convinced that the e� ort was

worthwhile. None the less, I would argue that although many people crit icizestandards (sometimes correctly), no-one is more aware of the shortcomings of the

process (and the end results) than those who struggle to make it work.

I am therefore delighted to have been given the opportunity by the Human

Factors and Ergonomics Society and the International Ergonomics Association to

stand back and take another look at our standardization work. Of course, I have

said much of this before in various forms and to di� erent audiences (Stewart 1998,1999). Anyone who read or attended these earlier sessions will be familiar with some

of the argumentsÐ it is di� cult to ® nd new ways to describe the same issues and the

same standardsÐ none the less this is a major opportunity to pull it all together and

*Author for correspondence. e-mail: [email protected]

ERGONOMICS, 2000, VOL. 43, NO. 7, 1030±1044

Ergonomics ISSN 0014-0139 print/ISSN 1366-584 7 online Ó 2000 Taylor & Francis Ltdhttp://www.tandf.co.uk/journals

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to give a more considered overview. However, before progressing, I would like to

make it clear which standardization activities I am reviewingÐ there are more than

you might suspect.

1.1. Standards are such fun that everyone wants one of their ownIn most people’s minds, one of the most basic and fundamental objectives of

standardization is to minimize unnecessary variations. Ideally, for any product

category, there is one standard that should be satis® ed and products which meet that

standard give their owners or users some reassurance about quality or about what

standards makers refer to as interoperability. Thus yachtsmen in Europe who buy alifejacket which meets EN 396 (EN 396: 1994 Lifejackets and personal buoyancy

aids) might reasonably expect it to keep them a¯ oat if they have the misfortune to

fall overboard. Similarly, an o� ce manager in the USA who orders A4 paper for his

photocopiers (ISO 216:1975) might reasonably expect paper which meets that

standard to ® t even though it is not the typical size used locally.

This brings us to a rather important point. It is often di� cult to achieve a singleagreed standard and a common solution is to have more than one standard. An

obvious example concerns paper size where there is the ISO A series (A0, A1, etc.),

the ISO B series (B0, B1, etc.) as well as US sizes (legal, letter, etc.). Although this

solves the standards makers’ problems in agreeing on a single standard, it is an

endless source of frustration for users of the standard as anyone who has forgottento check the paper source in an e-mailed document can testify.

However, there is another reason why there are more standards than one might

imagine, especially when it comes to user interface design issues. The reason is that

computer technology forms the basis of many di� erent industries and standards can

have an important impact on market success.In my corner of the standardization world as Chairman of ISO/TC 159/SC4

Ergonomics of Human System Interaction, I have enjoyed collaboration with a

number of other usability standards bodies including:

· ISO/IEC JTC1/SC35 Cultural and Linguistic Adaptability (was SC18/WG9

User System Interfaces and Symbols)

· ETSI/TC-HF

· IEEE P1201.2 User Interface Drivability

· ECMA TC 35 User System Interface

· CEN/TC122/WG5 Ergonomics of VDTs.

It is not just at the international level that there appears to be some duplication. In

the UK, the British Standards Institution mirror committee to SC4 published an

early version of the ® rst six parts of ISO 9241 as a British Standard, BS 7179:1990.

The prime reason for this was to provide early guidance for employers of users of

visual displays who wanted to use standards to help them to select equipment whichmet the requirements in the Schedule to the Health and Safety (D isplay Screen

Equipment) Regulations 1992. These regulations are the UK implementation of a

European Community Directive on the minimum safety and health requirements for

work with display screen equipment (90/270/EEC). Of course, as a spin-o� the

British Standards Institution (BSI) was able to generate revenue from selling these

standards several years before the various parts of ISO 9241 became available asBritish Standards.

1031Ergonomics user interface standards

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A similar process has taken place in the USA with the Human Factors and

Ergonomics Society (HFES) developing HFS 100 on Visual Display Terminal

Ergonomics as an ANSI-authorized Standards Developing Organization. More

recently there are two HFES standards development committees working on HFES

100 (a new version of HFS 100) and on HFES 200, which addresses user interfaceissues. It includes sections on accessibility, voice and telephony applications, colour

and presentation, and slightly re-written parts of the software parts of ISO 9241.

Although in this paper, I will focus solely on the work of ISO/TC159/SC4 The

Ergonomics of Human System Interaction, many of the comments are relevant to

other standards activit ies.

1.2. How the International Organization for Standardization worksThe International Organization for Standardization (ISO) comprises national

standards bodies from member states (see www.iso.ch for more information). Its

work is conducted by technical committees and sub-committees which meet every

year or so and are attended by formal delegations from participating members ofthat committee. In practice, the technical work takes place in Working Groups of

experts nominated by national standards committees who are expected to act as

independent experts. The standards are developed over a period of several years and

in the early stages the published documents may change dramatically from version to

version until consensus is reached (usually within a Working Group of experts). Asthe standard becomes more mature (from the Committee Draft Stage onwards),

formal voting takes place (usually within the parent sub-committee) and the draft

documents provide a good indication of what the ® nal standard is likely to look like.

Table 1 shows the main stages of ISO standards development.

1.3. How this paper is structuredIn § 2, the origins of ISO/TC159/SC4 and the work that has led to its main standards

published today, primarily the ISO 9241 series, are described. Section 3 explains how

we thought that ISO 9241 would be used to support system design decisions. I review

all the problems and issues that have led some to believe that standards are just too

Table 1. The main stages of ISO standards development.

WI Work ItemÐ an approved and recognized topic for a working group to beaddressing, which should lead to one or more published standards.

WD Working DraftÐ a partial or complete ® rst draft of the text of the proposedstandard.

CD Committee DraftÐ a document circulated for comment and approval within thecommittee working on it and the national mirror committees. Voting and approvalis required for the document to reach the next stage.

DIS Draft International StandardÐ a draft standard which is circulated widely forpublic comment via national standards bodies. Voting and approval is required forthe draft to reach the ® nal stage.

FDIS Final Draft International StandardÐ the ® nal draft is circulated for formal votingfor adoption as an International Standard.

IS International Standard. The ® nal published standard.

Documents may be reissued as further CDs and DISs.

1032 T . Stewart

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much trouble in § 4. In § 5, I argue that the bene® ts of the standards and, in some

ways more importantly, of the standardization process outweigh these admitted

disadvantages. F inally, I outline how this area of standards work might develop in

the future.

2. The origins of ISO/TC159/SC4

In the late 1970s, there was growing concern about the ergonomics of visual display

terminals (also called visual display units). The prime concern at that time concerned

the possibility that prolonged use (especially of displays with poor image quality) might

cause deterioration in the eyesight of users. However, since then several studies haveshown that ageing causes the main e� ect on eyesight and since display screen work can

be visually demanding, many people only discover this deterioration when they

experience discomfort from intensive display screen use. This can incorrectly lead them

to attribute their need for glasses to their use of display screens.

When a new work item to address this concern was proposed, the Information

Technology Committee decided that this was a suitable topic for the recently formedErgonomics Committee ISO/TC 159. The work item was allocated to the Sub-

committee ISO/TC 159/SC4 Signals and Controls and an inaugural meeting was held

at BSI in Manchester in 1983. The meeting was well attended with delegates from many

countries and a few key decisions were made.

At that time, there was a proliferation of o� ce-based systems and we decided tofocus on o� ce tasks (word processing, spreadsheets, etc.) rather than try to include

Computer Aided Design (CAD) or process control applications. We also decided that

we would need a multi-part standard to cover the wide range of ergonomics issues

which we believed needed to be addressed in order to improve the ergonomics of

display screen work. Six initial parts were identi® ed and working groups wereestablished (table 2). At the end of that ® rst meeting, one of the distinguished

participants, Professor Bengt Knave from Sweden, was heard to complain that we had

been meeting for three days and still had not standardized anything. Little did any of us

realize that it would be nearly 7 years before the ® rst parts of ISO 9241 would be

published and that it would take us until the end of the century to publish all 17 parts.

Table 3 shows the 17 parts of ISO 9241 Ergonomic requirements for o� ce workwith visual display terminals (VDTs). Table 4 shows the other human-system

interaction standards for which ISO/TC 159/SC4 is responsible.

3. How we intended ISO 9241 to be used

The structure of the standard was decided at a time when there were cleardistinctions between hardware and software and monochrome Cathode Ray Tube

(CRT) displays were the norm. The ® rst six parts were therefore primarily concerned

Table 2. Working Groups of ISO/TC159/SC4.

WG1 Fundamentals of controls and signalling methodsWG2 Visual display requirementsWG3 Control, workplace and environmental requirementsWG4 Task requirements (disbanded)WG5 Software ergonomics and human-computer dialogueWG6 Human-centred design processes for interactive systemsWG7 Ergonomics design of control centres

1033Ergonomics user interface standards

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Table 3. Parts and status of ISO 9241. Ergonomics requirements for o� ce work with visualdisplay terminals (VDTs).

Responsible Status atISO 9241 Working Group Dec 1999

Part 1Part 2Part 3Part 4Part 5Part 6Part 7Part 8Part 9Part 10Part 11Part 12Part 13Part 14Part 15Part 16Part 17

General introductionGuidance on task requirementsVisual display requirementsKeyboard requirementsWorkstation layout and postural requirementsGuidance on the work environmentRequirements for displays with re¯ ectionsRequirements for displayed coloursRequirements for non-keyboard input devicesDialogue principlesGuidance on usabilityPresentation of informationUser guidanceMenu dialoguesCommand dialoguesDirect manipulation dialoguesForm ® lling dialogues

WG6WG4 (disbanded)

WG2WG3WG3WG3WG2WG2WG3WG5WG5WG5WG5WG5WG5WG5WG5

ISISISISISISISIS

FDISISISISISISISISIS

Table 4. Other human system interaction standards for which ISO/TC 159/SC4 isresponsible.

ISOResponsible

WorkingStatusat Dec

Standards Group 1999

13406-1

13406-2

14915-1

14915-214915-314915-4TS 1607113407

TS 16982TR 1852911064-111064-211064-311064-411064-511064-611064-711064-8

Ergonomics requirements for ¯ at panel displaysÐ IntroductionErgonomics requirements for ¯ at panel displaysÐ Ergonomics requirementsSoftware ergonomics for multi-madia interfacesÐ Design principles and frameworkMultimedia control and navigationMedia selection and combinationDomain-speci® c multimedia aspectsAccessibilityHuman-centred design processes for interactivesystemsUsability methods supporting HC designHuman-centred lifecycle process descriptionsPrinciples for the design of control centresPrinciples of control suite arrangementControl room layoutWorkstation layout and dimensionsDisplays and controlsEnvironmental requirements for control roomsPrinciples for the evaluation of control centresErgonomics requirements for speci® capplications

WG2

WG2

WG5

WG5WG5WG5WG5WG6

WG6WG6WG8WG8WG8WG8WG8WG8WG8WG8

IS

FDIS

DIS

2nd CDDISWIWDIS

CDTR

FDISFDIS

ISWDWDWDWIWI

1034 T . Stewart

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with hardware (which, in our na õ È veteÂwe thought would be easier and less

contentious to standardize). However, even within this hardware domain, we

recognized the importance of job and task design in ensuring that users could work

safely, comfortably and e� cientlyÐ so Part 2 was inserted before the more technical

hardware oriented parts.Later, software parts (Parts 10 to 17) were added, re¯ ecting the di� erent styles of

user system interaction which were available at the time and additional hardware parts

were added to deal with re¯ ections (Part 7), colour displays (Part 8) and non-keyboard

input devices, e.g. the mouse (Part 9). The structure therefore re¯ ected the practicalities

and history of standard making and unfortunately is not very user-centred (one of thekey principles of ergonomics).

Although we did not make it explicit at the time, we had an underlying set of

assumptions about human-computer interaction (HCI) design activities and how the

standards would support these. These activities included:

· Analysing and de® ning system requirements

· Designing user-system dialogues and interface navigation

· Designing or selecting displays

· Designing or selecting keyboards and other input devices

· Designing workplaces for display screen users

· Supporting and training users

· Designing jobs and tasks.

Table 5 shows how we anticipated the standards being used.

4. So what went wrong?Looking back, I believe that there were a number of things which went wrong or

perhaps, more accurately, did not quite go according to plan. It has been pointed out

that hindsight has 20/20 vision. Maybe we could have anticipated more of the

problems, but I am not certain that anyone really understood the implications of what

we were doing. Certainly, until that time, much standardization work had dealt with far

more limited scopes and much more established technologies. For example, there is anentire Technical Committee which specializes in `Light gauge metal containers’

(TC52). Our sub-committee was attempting to address all the ergonomics issues

associated with interactive systems.

None the less, I believe that there were ® ve main areas where our approach could

have been better:

· It took much longer than we thought

· We and our standards were misunderstood

· We did not appreciate how political it was or would get

· We tried to be too clever

· We had too much help at times.

These points are discussed in more detail below.

4.1. It took much longer than we thoughtThe disappointment of one delegate at the meeting in Manchester has already beenmentioned but none of us appreciated just how long the process would take. One of the

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nu

ed)

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Table

5.

(con

tinu

ed)

HC

IA

ctiv

ity

Rel

evan

tpart

of

ISO

9241

Co

nte

nts

ISO

9241-1

2:1

998

Pre

sen

tati

on

of

info

rmati

on

Spec

i®c

soft

ware

ergo

nom

ics

issu

esin

vo

lved

inre

pre

senti

ng

an

dp

rese

nti

ng

info

rmati

on

invis

ual

form

.It

incl

ud

esgu

idan

ceo

nw

ays

of

rep

rese

nti

ng

com

ple

xin

form

ati

on

,sc

reen

layo

ut

an

dd

esig

nas

wel

las

the

use

of

win

dow

s.T

her

eis

alr

ead

ya

sub

stanti

al

bod

yo

fm

ate

rial

available

ingu

idel

ines

and

reco

mm

end

ati

ons

an

dth

isp

art

repre

sents

adis

till

ati

on

of

the

most

use

ful

an

dre

levant

ones

.

Des

ign

ing

or

sele

ctin

gk

eyb

oard

san

do

ther

inpu

td

evic

es

ISO

9241-4

:1998

Key

board

requ

irem

ents

Alp

han

um

eric

key

board

spec

i®ca

tio

nand

des

ign

(in

term

so

fth

eo

per

ati

on

of

the

key

san

dit

ser

go

no

mic

qu

aliti

es)

isco

ver

ed.

Inadd

itio

nto

des

ign

spec

i®ca

tio

ns,

this

part

als

oco

nta

ins

apro

po

sed

use

rp

erfo

rman

cete

stas

an

alt

ernati

ve

rou

teto

con

form

ance

.It

dea

lsw

ith

the

ergon

om

icasp

ects

of

the

key

bo

ard

,n

ot

the

layo

ut

wh

ich

issp

eci®

edin

ISO

9995

Key

bo

ard

layo

uts

for

text

o�

cesy

stem

s.

ISO

9241-9

:2000

Non

-key

board

inp

ut

dev

ices

Erg

ono

mic

requ

irem

ents

for

po

inti

ng

dev

ices

incl

udin

gth

em

ou

se,

track

erb

all

etc.

,w

hic

hca

nb

euse

din

con

junct

ion

wit

ha

vis

ual

dis

pla

yte

rmin

al.

Des

ign

ing

wo

rkp

lace

sfo

rd

isp

lay

scre

enuse

rsIS

O9241-5

:1998

Wo

rkst

ati

on

Erg

ono

mic

req

uir

emen

tsfo

ra

vis

uald

ispla

yte

rmin

al

wo

rkst

ati

on

that

will

allo

wth

eu

ser

toado

pt

aco

mfo

rtable

an

de�

cien

tp

ost

ure

.IS

O9241-6

:1998

Gu

idan

ceo

nth

ew

ork

envir

onm

ent

En

vir

on

men

tal

con

sider

ati

ons

(vis

ual,

aco

ust

icand

ther

mal)

.

Sup

po

rtin

gan

dtr

ain

ing

use

rsIS

O9241-1

3:1

998

Use

rguid

ance

Rec

om

men

dati

on

sfo

rth

ed

esig

nev

alu

ati

on

of

use

rgu

idan

ceatt

ribu

tes

of

soft

ware

use

rin

terf

ace

sin

clu

din

gpro

mp

ts,

feed

back

,st

atu

son

-lin

eh

elp

an

der

ror

manage-

men

t.

Des

ign

ing

job

san

dta

sks

ISO

9241-2

:1992

Gu

idan

ceo

nta

skre

qu

irem

ents

Gu

idan

ceo

nth

ed

esig

nof

dis

pla

ysc

reen

task

sb

ase

don

nea

rly

half

ace

ntu

ryof

rese

arc

han

dorg

an

izati

onal

pra

ctic

ein

soci

o-t

ech

nic

al

syst

ems.

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reasons why the process is slow is that there is an extensive consultation period at each

stage of development with time being allowed for national member bodies to circulate

the documents to mirror committees and then to collate their comments.

Another reason is that Working Group members can spend a great deal of time

working on drafts and reaching consensus only to ® nd that the national mirrorcommittees reject their work when it comes to the o� cial vote. It is particularly

frustrating for project editors to receive extensive comments (which must be

answered) from countries who do not send experts to participate in the work. Of

course, the fact that the work is usually voluntary means that it is di� cult to get

people to agree to work quickly.

4.2. W e and our standards were misunderstoodWhile I do not accept that we have produced bad standards (at least in our committee),

our standards have been criticized for being too generous to manufacturers in some

areas and too restrictive in other areas. The `over-generous’ criticism misses the point

that most standards are setting minimum requirements and in ergonomics we must bevery cautious about setting such levels. However, there certainly are areas where being

too restrictive is a problem. Examples include the following.

(1) ISO 9241-3:1992 Ergonomics requirements for work with V DTs: V isual displayrequirements. This standard has been successful in setting a minimum standard for

display screens, which has helped purchasers and manufacturers. However, it isbiased towards Cathode Ray Tube (CRT) display technology. An alternative

method of compliance based on a performance test (which would be technology

independent) is still under development but was approved in December 1999 as a

Draft International Standard and should therefore be ® nalized in the near future.

(2) ISO 9241-9:2000 Ergonomics requirements for work with V DTs: Non keyboardinputdevices. Thisstandard hassu� ered because technologicaldevelopmentswere faster

than either ergonomics research or standards making. Although there has been an

urgent need for a standard to help usersto becon® dent in theergonomicsclaimsmadefor

newdesignsofmiceand other input devices, the lack of reliabledata forced thestandards

makers to slow down or run the risk of prohibiting newer, even better solutions.

The biggest area of misunderstanding is that some people seem surprised todiscover that user interface standards not only do not solve all the problems in user

interface design, but also they do not even address some of the most di� cult parts of

design. I am really not sure where this misunderstanding arose. Even though we, in

the standards community, believe that standards are part of the solution, I do not

know anyone who believes that they are the whole story or thinks that they shouldbe. Elizabeth Buie (1999) has published an excellent review of such problems and

explains how standards ® t into the overall picture.

4.3. W e did not appreciate how political it was or would getAlthough ergonomics standards are generally concerned with such mundanetopics as keyboard design or menu structures, they none the less generate

considerable emotion amongst standards makers. Sometimes this is because the

resulting standard could have a major impact on product sales or legal

liabilities. At other times the reason for the passion is less clear. None the less,

the strong feelings have resulted in painful experiences in the process of

standardization, especially for me as committee chairman. These have included

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the following.

(1) Undue influence of major players. Large multinational companies can try to

exert undue influence by dominating national committees. Although draft

standards are usually publicly available from national standards bodies, theyare not widely publicized. This means that it is relatively easy for well informed

large companies to provide sufficient experts at the national level to ensure that

they can virtually dictate the final vote and comments from a country.

(2) `Horse trading’ and bargaining to achieve agreement. End users’ requirements

can be compromised as part of `horse trading’ between conflicting viewpoints.In the interests of reaching agreement, delegates may resort to making political

trade-offs largely independent of the technical merits of the issue.

(3) Uncritical support for favourite ideas. National pride can lead to uncritical

support for a particular approach or methodology. In theory, participants in

Working Group meetings are experts nominated by member bodies in the

different countries. They are not there to represent a national viewpoint but aresupposed to act as individuals. However, as one disillusioned expert explained

to me s̀ometimes the loudest noise at a Working Group meeting is the grinding

of axes’ .

4.4. W e tried to be too cleverOne of the criticisms we face as ergonomics and human factors specialists is that we

generally spend too much time talking to ourselves. I am not referring to some

abnormal mental state of delusion but rather the tendency amongst all experts to be

more interested in the views of their fellows than in addressing the wider public. The

same criticism can be levelled at standards makers. Indeed, in ISO, the formal rulesand procedures for operating seem to encourage an elitist atmosphere with standards

written for standards enthusiasts. ISO has recognized this and is attempting to make

the process more customer focused but such changes take time. Within our

committees, these procedures and rules have reinforced our elitist tendencies and

sometimes resulted in standards that leave much to be desired in terms of brevity,

clarity and usability. There are three contributory factors:

(1) The use of stilted language and boring formats. The unfriendliness of the

language is illustrated by the fact that although the organization is known by

the acronym ISO, its full English title is the International Organization for

Standardization. The language and style are governed by a set of Directives andthese encourage a wordy and impersonal style.

(2) Problems with translation and the use of `near English’ . There are three official

languages in ISOÐ English, F rench and Russian. In practice, much of the work

is conducted in English, often by non-native speakers. As someone who only

speaks English, I have the utmost respect for those who can work in more thanone language. However, the result of this is that the English used in standards is

often not quite correctÐ it is `near English’ . The words are usually correct but

their combination often makes the exact meaning unclear. These problems are

exacerbated when the text is translated.

(3) Confusions between requirements and recommendations. In ISO standards, there

are usually some parts which specify what has to be done to conform to thestandard. These are indicated by the use of the word s̀hall’ . However, in

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ergonomics standards, we often want to make recommendations as well. These

are indicated by the use of the word s̀hould’ . Such subtleties are often lost on

readers of standards, especially those in different countries. For example, in the

Nordic countries, they follow recommendations (shoulds) as well as require-

ments (shalls), so the distinction is diminished. In the USA, they tend to ignorethe s̀houlds’ and only act on the s̀halls’ .

4.5. W e had too much help at timesThis might sound like an unlikely problem but given the long time-scale mentioned

above it can be a signi® cant factor in slowing down the process. The reason is thatmany experts are only supported by their organizations for a relatively short time

and are then replaced by other experts. Every time a new expert joins the Working

Group, there is a tendency to spend a lot of time explaining the history and to some

extent starting the process again. Similarly, each expert feels obliged to make an

impact and suggest some enhancement or change in the standard under

development. Since the membership of Working Groups can change at virtuallyevery meeting (which are usually 3 or 4 months apart), it is not uncommon for long-

standing members to ® nd themselves reinstating material which was deleted two or

three meetings previously (as a result of a particularly forceful individual).

5. It was not all badAs I mentioned at the beginning of this paper, neither my colleagues in

standardization nor I would spend so much time and e� ort if we did not believe

the results would be worthwhile. Looking back, some things really worked well and

in mitigation of the criticisms, I would argue the following:

· Slower is not necessarily worse

· Structure and formality can be a help as well as a hindrance

· Standards do not have to be unduly restrictive

· The bene® ts do not just come from the standards themselves

· Being international makes it all worthwhile.

· These points are argued in more detail below.

5.1. Slower is not necessarily worseStandards making is painfully slow. I am not suggesting that this is good, especially

in such a fast moving area as user interface design. However, there are some bene® ts

that come directly from the pace of the process, in addition to the widespreadconsultation which I have already mentioned.

One bene® t is that when the technology is moving quicker than the standards

makers can react, it does make it clear that certain types of standards may be

premature. For example, ISO 9241-14:1997 Menu dialogues was originally proposed

when character-based menu-driven systems were a popular style of dialogue design.Its development was delayed considerably for all manner of reasons (many beyond

our control). However, these delays meant that the ® nal standard was relevant to

pull down and pop-up menus which had not even been considered when the standard

was ® rst proposed.

Another bene® t is that during the development process, those who may be

a� ected have the opportunity to prepare for the standard. Thus by the time ISO9241-3:1992 Visual display requirements was published, many manufacturers were

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able to claim that they already produced monitors that met the standard. They had

not been in that position when the standard was ® rst proposed and although they

might like to argue that they would have been improving the design of their displays

anyway, I am not convinced that this is entirely true. Certainly the standards

provided a clear target for both demanding consumers and quality manufacturers.

5.2. Structure and formality can be a help as well as a hindranceOne of the bene® ts of standards is that they do represent a rather simpli® ed and

structured view of the world. There is also a degree (sometime excessive) of discipline

in what a standard can contain and how certain topics can be addressed.Manufacturers (and ergonomists) frequently make wildly di� erent claims about

what represents good ergonomics. This is a major weakness for our users who may

conclude that all claims are equally valid and there is no sound basis for any of it.

Standards force a consensus and therefore have real authority in the minds of our

users. Achieving consensus requires compromises, but then so does life.

The formality of the standards mean that they are suitable for inclusion in formalprocurement processes and for demonstrating best practice. In the UK at least, parts

of ISO 9241 may be used by suppliers to convince their customers that visual display

screen equipment and its accessories meet good ergonomics practice. Of course, they

can also be `abused’ in this way with over-eager salesmen misrepresenting the legal

status of standards but that is hardly the fault of the standards makers.

5.3. Standards do not have to be unduly restrictiveI have already described the problem that was experienced during the development

of ISO 9241 caused by the technology being developed faster than we could reach

agreement on the standards. I have also explained that ISO 9241-3:1992 now has anAmendment which o� ers a method of complying with design requirements through

user testing which is therefore relatively technology independent.

However, standards that specify how products should be made are not the only

types of ergonomics standards which are possible. In late 1992, we started work on a

process standard ISO 13407:1999 Human-centred design processes for interactive

systems, which aims to provide guidance for project managers to help them to followa human-centred design process. By undertaking the activities and following the

principles described in the standard, managers can be con® dent that the resulting

systems will be usable and will work well for their users.

The standard describes four principles of human-centred design:

(1) active involvement of users (or those who speak for them);

(2) appropriate allocation of function (making sure human skill is used properly);

(3) iteration of design solutions (allowing time for iteration in project planning);

(4) multi-disciplinary design (but beware of large design teams);

and four key human-centred design activities:

(1) understand and specify the context of use (make it explicitÐ do not assume that

it is obvious);

(2) specify user and organizational requirements (note that there will be a variety ofdifferent viewpoints and individual perspectives);

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(3) produce design solutions (note plural, multiple designs encourage creativity);

and

(4) evaluate designs against requirements (involves real user testing not just

convincing demonstrations).

In order to claim conformance, the standard requires that the procedures used,

the information collected and the use made of results are speci® ed (a checklist is

provided as an annex to help). We have developed this approach to conformance

in a number of parts of ISO 9241 since so many ergonomics recommendations

are context-speci® c. Thus there is often only one s̀hall’ in these standards whichgenerally prescribes what kind of evidence is required to convince another party

that the relevant recommendations in the standard have been identi® ed and

followed.

There has already been considerable international interest in ISO 13407 and we

believe that there will be increasing demands from large customers for evidence that

their system suppliers follow this kind of process.

5.4. The bene® ts do not just come from the standards themselvesThere are several ways in which ergonomics standardization activit ies can add value

to user interface design apart from the standards themselves, which are the end

results of the process.I have already mentioned that some of those manufacturers who recruited

ergonomics and human factors people to defend themselves against standards (my

personal and probably somewhat biased view) found that these individuals could

add value to the design of user interfaces. Although many of these experts have now

joined the ranks of independent consultants, I believe that they had a signi® cantimpact in terms of raising awareness about the importance of usability.

In 1997, the US National Institute of Standards and Technology (NIST) initiated

a project (Industry USability Reporting, IUSR) to increase the visibility of software

usability. They were helped in this endeavour by prominent suppliers of software and

representatives from large consumer organizations. One of the key goals was to

develop a common usability reporting format (Common Industry Format, CIF).This is currently being piloted. Although the e� ort is independent of other

standardization bodies or activities, the CIF has been developed to be consistent

with ISO 9241 and ISO 13407 and is viewed by the IUSR team as `an

implementation of that ISO work’ . I believe this activity in itself will have a major

impact on software usability (http://www.nist.gov/iusr).In the hardware arena, many people are aware of the TCO 99 sticker which

appears on computer monitors and understand that it is an indication of ergonomic

and environmental quality. What they may not know is that TCO is the Swedish

Confederation of White Collar Trades Unions and that ISO 9241 was used as a

major inspiration for its original speci® cation. They publish information in Englishand details are available on their website at http://www.tco.se/eng/index.htm.

5.5. Being international makes it all worthwhileF inally, I am a strong believer in taking a global perspective on ergonomics (and

indeed on many other issues). Although there are national and regional di� erences in

populations, the world is becoming a single market with the major suppliers taking aglobal perspective.

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Variations in national standards and requirements not only increase costs and

complexity, but they also tend to compromise individual choice. Making standards

international is one way of ensuring that they have impact and can help to improve

the ergonomics quality of products for everyone. That has to be a worthwhile

objective. Table 6 shows the member countries of ISO/TC159/SC4.

6. Next steps

Having taken more than 17 years to develop ISO 9241, you might be forgiven for

believing that we would want a rest . In fact, what the experience has taught us is

that there is a great deal that we would have done di� erently all those years ago,had we known then what we know now. In ISO/TC 159/SC4, we have recently

been trying to apply customer-centred methods to our own work. Recognizing

how long it takes to develop standards and that we do not have unlimited

resources, we have been planning our strategy and we have come to some

tentative conclusions for our ® ve-year plan. We have identi® ed a number of key

standards that we would like to have in place by that time. One major di� erencefrom ISO 9241 is that we do not intend to restrict ourselves to o� ce tasks nor

indeed do we believe that we should be developing a single family of standards

with a common scope or structure.

However, we have identi® ed seven areas where we believe that we can identify a

need for standards and a clear population of potential readers of the standardsdocuments.

Although discussions are still at a very early stage, we envisage standards being

developed (or existing standards being updated) to support the following.

· Visual displaysÐ design and assessment tools for manufacturers, designers,Original Equipment Manufacturers (OEM), testers, evaluators and buyers

· Physical input devicesÐ design and assessment tools for manufacturers,

testers and selection combination tools for buyers

· Voice/speech interface design requirements for application developers

· Design process guidance for project managers and designers

· Workplace customization use and selection for system designers inorganizations

· Interaction, dialogue, navigation and presentation requirements and

guidance for applications designers

· Evaluation, metrics and measurement criteria guidance for end users and

managers and test methods for usability experts.

Although I believe that standards are an important tool for the ergonomist, many

people ® nd them di� cult to understand and use. The best way to really understand

what is going on in standards is to get involved. This will give you advance warning

Table 6. Members of ISO/TC159/SC4 Ergonomics of Human-System Interaction.

`P’ members(Participants)

Austria, Belgium, Canada, Czech Republic, China, Denmark,F inland, F rance, Germany, Ireland, Italy, Japan, Korea, Netherlands,Norway, Poland, Slovakia, Spain, Sweden, Thailand, UK and USA

`O’ members(Observers)

Australia, Hungary, Mexico, Romania and Tanzania

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of future standards, the opportunity to in¯ uence the content of standards and an

understanding of the context in which they have been developed. You will then ® nd

it much easier to make e� ective use of standards. If you would like more information

on ISO, you will ® nd their website an excellent starting point with links to national

and other standards sites (http://www.iso.ch).

Acknowledgements

I would like to thank my many colleagues from around the world with whom I have

had the pleasure of working to develop standards over the past 17 years.

ReferencesBU IE, E. 1999, HCI standards: A mixed blessing, Interactions, 6 (2), 36 ±42.STEWART, T. 1998, Ergonomics standardsÐ the good, the bad and the ugly, in M. A. Hanson

(ed.), Contemporary Ergonomics 1998 (London: Taylor & Francis), 3 ±7.STEWART, T. 1999, Experiences (painful and good) developing HCI standards, Proceedings of

Interact 99, Volume II, Edinburgh, 30th August to 3rd September (Swindon: BritishComputer Society), 196 ±200.

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