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International data on anthropometry
BOOKS International data on anthropometry Hans 14/.Jffrgens, /var A. Aune and Ursula P/eper I LO Occupational Safety and Health Series No 65, International Labour Office, Geneva, 1990. I SBN 92-2-106449o2, ISSN 0078-3129, pp 113 + vii, 360 references, SwFr 1750. This valuable collection of anthropometric data was compiled in a research programme at the Federal Institute of Occupational Safety and Health in Dortmund, and should be a companion to the NASA Anthropometric Source Book on the bookshelves of any ergonomist practising workplace or product design. While the NASA compilation is an excellent source of North American and military data, the present report adds data obtained for the rest of the world. It lists many fresh data sources from Latin America, and those from the Near East, India, Japan and South-East Asia will be particularly welcomed by designers in manufacturing companies supplying the expanding worldwide markets. The tabulated data give estimates for the 5th, 50th and 95th percentile values of 19 body dimensions for men and women within the age range of 25-45 years, but the data are extrapolated to the year 2000. Although the 19 dimensions cannot cover every design problem, they have been well chosen with the needs of workplace design in mind, and include functional dimensions such as seated eye height and elbow-grip length. The estimations of the percentile data have inevitably involved various assumptions and compromises, as discussed later, but the authors are to be congratulated on attempting such an ambitious project. The report divides into two parts, the first of which is the generally useful compilation of anthropometric data. The second part is a critical analysis directed at "establishing international anthropometric standards for consumer goods and the design of workplaces". This is important to researchers in the field of anthropometry and to those involved directly in standards work, but will be of less interest to the general ergonomics practitioner. There is a growing need for anthropometric standards in view of international economic and commercial developments, but the aim for simplicity in standardisation should not be allowed to obscure real local variations. This is a difficult problem for designers (and for anthropometrists), but is an important issue. Ergonomists in the developing countries are reporting many problems experienced with the use of western-manufactured products due to designs which do not take account of the significant differences in body size, body proportions or physiology. In their Introduction, the authors explain this background to their work, and point out that there should be concern for appropriate anthropometric standards in developed countries as well, since they have found similar problems in Germany when using international standards. One of their aims in compiling the worldwide anthropometric statistics has therefore been to start a debate on whether "an international harmonisation of consumer goods and workplace design is necessary and possible". Their analysis is therefore important from this point of view, but the conclusions the authors draw from the
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Applied Ergonomics
December 1991
analysis need careful consideration. It has to be said that Prof Jiirgens and his colleagues faced enormous difficulties in attempting such a compilation (from lack of data in many areas, surveys whose subjects were atypical of the national population represented, lack of information on measurement techniques, and complications in taking account of secular trends when using survey data collected at different times). In order to deal with these, the study was undertaken in six stages: (i) collecting all available data from both scientific and non-scientific sources; (ii) reviewing the measurement procedures used in these studies; (iii) filling in the gaps by "extrapolation of missing data"; (iv) standardising the data for the year 2000; (v) compiling the database; (vi) classifying the results to see whether international harmonisation is possible. Of the stages in the reduction process, (iii) and (iv) are obviously the most difficult and controversial. Unfortunately, this is where the main weakness of the report is apparent, since it gives almost no information on the assumptions and methodology used to extrapolate the data. In order to place confidence in the data tables it is necessary to know what data were missing from the survey sources used and how they were estimated, and even more importantly, how the secular trends in different countries have been predicted to extrapolate the data to the year 2000. This last is a particular difficulty since evidence on secular trends is so sparse. Many societies have changed dramatically over the last generation, and population migration will have been superimposed on the secular trends. I would have been happier if the authors had chosen to look at the current picture, using available evidence on past trends to correct historical data wherever possible; or better still, have included the data for both 1990 and 2000. Good anthropometric data collections are so rare that I dislike carping about this compilation. However, I have to express a second worry about the collection of data used to produce the data tables. The anthropometric statistics were collected from many sources, some of which were unpublished and therefore not referenced in the report, and these apparently included original data from anthropological and medical sources which must have required considerable interpretation to be useful. Although I recognise that this can be very valuable in experienced hands such as those of Prof J/irgens, it still needs to be documented and justified. A further point is that the data tables contained in this report have been sub-divided into 20 population groups, largely coinciding with geographical regions, To some extent, perhaps, these have been influenced by availability of data. France, for example, is given a region to itself, despite its ethnic affmities with parts of Germany (which is split between the Northern European group and the Central European group) or parts of Britain, which comes into the Central European group. This may have been entirely pragmatic, but such a grouping strategy should surely have a more detailed ethnological or dimensional justification. This is indicated but again not explained in the report. Later analysis in the final chapter is even more speculative, where the authors investigate the possibility of using a simpler classification in which the 20 population
groups are further condensed to give the statistics for two international 'northern' and 'southern' (or large and small) groups. Nethertheless, in practical terms this may not matter to designers using the tabulated data, and the compilation is valuable for identifying and highlighting the regional variations. It seems to me that this report is not only a starting point for debate. It also identifies many of the problems experienced in collating anthropometric data, and some consideration of these could help to improve the methodological framework used in data collecting. If this could be standardised internationally, we could be more confident that the data we use from different sources are valid and comparable. Might this not be more valuable than standardising the actual data used in design?
Christine Haslegrave Workspace, equipment and tool design Anti Mital and Waldemar Karwowski (Eds)
Elsevier; Amsterdam-Oxford-NewYork-Tokyo, 1991, pp 369 + ix. This, the 15th in the 'Advances in Human Factors/ Ergonomics' series from Elsevier, continues the mixed fortunes which have beset this set of publications. The intentions of the book, as set out by the Editors, are to make state-of-the-art ergonomics information, relevant to the design of workspaces, equipment and tools, available to those who require this ]¢nowledge in their day-to-day work. They required their authors to review the literature, summarise the present state in a usable form and provide design information, as well as noting gaps in knowledge. Each chapter, taken on its own, follows the Editors' format. Many, however, are disappointing on their reworking of classical data from, for example, van Cott & Kincaide, Grandjean or McCormick. Repetition, for example, of anthropometry, force exertion and maintenance requirements suggest that a firmer editorial hand would have aided the readability and structure of the book. Consistency of type faces would have improved the legibility
of a number of the chapters, surely not too much to ask of word-processed contributions. Perhaps the criticisms arise from the disappointment that a text which is clearly about a most important, perhaps the most important, focus for the ergonomist's attention has not given rise to a book which would attract the engineer, manager or designer. There are many good features. The requirements for good computer models, and the section on the utility of these models, are useful and important. The emphasis, in Kroemer's chapter, on the need for good criteria to evaluate good measurements is surely welcome. Too often the data are assessed on classical beliefs - for example, the idea that the lowest class of motion is the best (p 70). The recognition of the multivariate nature of the workplace design problem is also well brought out in several of the contributions. The book - which has no index - is in three sections. The first, on workspace design, has chapters on anthropomerry, computer models for ergonomic accommodation, industrial workplace design, sitting at work, designing for workspace safety and design for maintenance. The four chapters of the equipment and tool design section which follows are on clearance and access dimensions, anthropometry in machine guarding, the design and use of hand tools and a chapter on displays and controls. The final section has three chapters. One is on designing and maintaining underground mining equipment, one on warning signs and labels and the last on designing for older adults. So who would use this book? Teachers prepared to put in the effort to select sections to match their presentations would find much useful material brought together here. Ergonomists in practice may find useful sections. The industrial engineer or manager, who should be using it, will also have to work hard at it. If they do, it will be a useful guide for many aspects of their work. My fear is that many will be put off by the loose overall structure of the work. What might have been a structured text for the user, with a coherent logic and carefully presented recommendations, is rather a mixed bag. The field is still open for a good applied ergonomics text in this area.
E.N. Corlett
Applied Ergonomics
December 1991
415
414
Applied Ergonomics
December 1991
analysis need careful consideration. It has to be said that Prof Jiirgens and his colleagues faced enormous difficulties in attempting such a compilation (from lack of data in many areas, surveys whose subjects were atypical of the national population represented, lack of information on measurement techniques, and complications in taking account of secular trends when using survey data collected at different times). In order to deal with these, the study was undertaken in six stages: (i) collecting all available data from both scientific and non-scientific sources; (ii) reviewing the measurement procedures used in these studies; (iii) filling in the gaps by "extrapolation of missing data"; (iv) standardising the data for the year 2000; (v) compiling the database; (vi) classifying the results to see whether international harmonisation is possible. Of the stages in the reduction process, (iii) and (iv) are obviously the most difficult and controversial. Unfortunately, this is where the main weakness of the report is apparent, since it gives almost no information on the assumptions and methodology used to extrapolate the data. In order to place confidence in the data tables it is necessary to know what data were missing from the survey sources used and how they were estimated, and even more importantly, how the secular trends in different countries have been predicted to extrapolate the data to the year 2000. This last is a particular difficulty since evidence on secular trends is so sparse. Many societies have changed dramatically over the last generation, and population migration will have been superimposed on the secular trends. I would have been happier if the authors had chosen to look at the current picture, using available evidence on past trends to correct historical data wherever possible; or better still, have included the data for both 1990 and 2000. Good anthropometric data collections are so rare that I dislike carping about this compilation. However, I have to express a second worry about the collection of data used to produce the data tables. The anthropometric statistics were collected from many sources, some of which were unpublished and therefore not referenced in the report, and these apparently included original data from anthropological and medical sources which must have required considerable interpretation to be useful. Although I recognise that this can be very valuable in experienced hands such as those of Prof J/irgens, it still needs to be documented and justified. A further point is that the data tables contained in this report have been sub-divided into 20 population groups, largely coinciding with geographical regions, To some extent, perhaps, these have been influenced by availability of data. France, for example, is given a region to itself, despite its ethnic affmities with parts of Germany (which is split between the Northern European group and the Central European group) or parts of Britain, which comes into the Central European group. This may have been entirely pragmatic, but such a grouping strategy should surely have a more detailed ethnological or dimensional justification. This is indicated but again not explained in the report. Later analysis in the final chapter is even more speculative, where the authors investigate the possibility of using a simpler classification in which the 20 population
groups are further condensed to give the statistics for two international 'northern' and 'southern' (or large and small) groups. Nethertheless, in practical terms this may not matter to designers using the tabulated data, and the compilation is valuable for identifying and highlighting the regional variations. It seems to me that this report is not only a starting point for debate. It also identifies many of the problems experienced in collating anthropometric data, and some consideration of these could help to improve the methodological framework used in data collecting. If this could be standardised internationally, we could be more confident that the data we use from different sources are valid and comparable. Might this not be more valuable than standardising the actual data used in design?
Christine Haslegrave Workspace, equipment and tool design Anti Mital and Waldemar Karwowski (Eds)
Elsevier; Amsterdam-Oxford-NewYork-Tokyo, 1991, pp 369 + ix. This, the 15th in the 'Advances in Human Factors/ Ergonomics' series from Elsevier, continues the mixed fortunes which have beset this set of publications. The intentions of the book, as set out by the Editors, are to make state-of-the-art ergonomics information, relevant to the design of workspaces, equipment and tools, available to those who require this ]¢nowledge in their day-to-day work. They required their authors to review the literature, summarise the present state in a usable form and provide design information, as well as noting gaps in knowledge. Each chapter, taken on its own, follows the Editors' format. Many, however, are disappointing on their reworking of classical data from, for example, van Cott & Kincaide, Grandjean or McCormick. Repetition, for example, of anthropometry, force exertion and maintenance requirements suggest that a firmer editorial hand would have aided the readability and structure of the book. Consistency of type faces would have improved the legibility
of a number of the chapters, surely not too much to ask of word-processed contributions. Perhaps the criticisms arise from the disappointment that a text which is clearly about a most important, perhaps the most important, focus for the ergonomist's attention has not given rise to a book which would attract the engineer, manager or designer. There are many good features. The requirements for good computer models, and the section on the utility of these models, are useful and important. The emphasis, in Kroemer's chapter, on the need for good criteria to evaluate good measurements is surely welcome. Too often the data are assessed on classical beliefs - for example, the idea that the lowest class of motion is the best (p 70). The recognition of the multivariate nature of the workplace design problem is also well brought out in several of the contributions. The book - which has no index - is in three sections. The first, on workspace design, has chapters on anthropomerry, computer models for ergonomic accommodation, industrial workplace design, sitting at work, designing for workspace safety and design for maintenance. The four chapters of the equipment and tool design section which follows are on clearance and access dimensions, anthropometry in machine guarding, the design and use of hand tools and a chapter on displays and controls. The final section has three chapters. One is on designing and maintaining underground mining equipment, one on warning signs and labels and the last on designing for older adults. So who would use this book? Teachers prepared to put in the effort to select sections to match their presentations would find much useful material brought together here. Ergonomists in practice may find useful sections. The industrial engineer or manager, who should be using it, will also have to work hard at it. If they do, it will be a useful guide for many aspects of their work. My fear is that many will be put off by the loose overall structure of the work. What might have been a structured text for the user, with a coherent logic and carefully presented recommendations, is rather a mixed bag. The field is still open for a good applied ergonomics text in this area.
E.N. Corlett
Applied Ergonomics
December 1991
415