1 ANTHROPOMETRIC THEORY
1.1 ANTHROPOMETRY
People’s historic involvement with body size was discussed in the Introduction. However, the science dealing specifically with the measurement of the human body to determine differences in individuals, groups, etc., is termed anthropometry. Pioneering work in this field dates back to the Belgian mathematician, Quetlet, who in 1870 published his Anthropometrie and is credited not only with founding and formalizing the science, but also with having created the term “anthropometry” itself. The origins of physical anthropology can be traced even further back to the late 18th century and Linne, Buffon, and White, who first developed the science of comparative racial anthropometry.
During the course of time, a significant amount of anthropometric data has been amassed. Unfortunately for the designer, however, the thrust of much of the efforts in this area was for taxonomic purposes, physiological studies, etc., and not primarily for the ergonomic implications of body size. It was not until the 1940s that the need for anthropometric data, generated in a variety of industrial fields, but primarily in the aircraft industry, began to develop and increase. The Second World War naturally provided much of the impetus, and even today it is in the military-industrial sector that much of the anthropometric research is generated. Although the discipline has fallen within the purview of the anthropometrist, anatomist, or ergonomist, it is time for the architect and interior designer to become more aware of the data available and its applicability to the design of interior spaces.
If anthropometry is viewed mainly as exercises in simple measurement and nothing more, one might conclude that the dimensional data could be gathered simply and effortlessly. Nothing, however, could be further from the truth. There are many complicating factors and difficulties involved. One such factor is that body sizes vary with age, sex, race, and even occupational group. For example, Chart 1-1 shows statistics on the statures (body height) of samples from various
national groups. The variation in stature is quite significant, ranging from 160.5 cm, or 63.2 in, for the Vietnamese to a high of 179.9 cm, or 70.8 in, for the Belgian—a range of 19.4 cm, or slightly more than 7.5 in.
aMean values except where ranges are given.
Chart 1-1. Statistics on the statures in centimeters and certain other characteristics of 26 samples. From Chapanis, Ethnic Variables in Human Factors Engineering.
Perhaps an even more dramatic example of ethnic variability, however, is a comparison of the difference in stature of the smallest males on record with the largest, as shown in Figure 1-1. D.F. Roberts notes that the former, the Pigmies of Central Africa, have a mean stature of 143.8 cm, or about 56.6 in, while the tallest males, for whom records are available, are the Northern Nilotes of Southern Sudan, with a mean stature of 182.9 cm, or 72 in—a range of 39.1 cm, or about 15.4 in.1
Figure 1-1. Comparison of difference in stature of the tallest Northern Nilote of Southern Sudan with the stature of the smallest Pigmy of Central Africa. Data from Chapanis, Ethnic Variables in Human Factors Engineering.
Age is another significant factor in body size. Full growth, with respect to body dimensions, peaks in the late teens and early twenties for males and usually a few years earlier for females. Subsequent to maturity, body dimension for both sexes actually decreases with age, as illustrated in Figure 1-2. In terms of the anthropometry of elderly people, a study in England suggested that body size of elderly women was smaller than the body size of young women. It was also pointed out, however, that to some extent the difference could be attributable not only to the fact that the elderly sample was obviously drawn from an earlier generation but to the aging process itself. Another conclusion of the study was the reduction in upward reach among elderly people.
Figure 1-2. Relative change in height with age over the mean for men and women aged 18-24 years. Data from National Health Survey.
Socioeconomic factors also impact significantly on body dimensions.
The nutrition available to those with higher incomes creates, for example, freedom from childhood disease and contributes to body growth, as illustrated in Figure 1-3. Socioeconomic status also reflects a relationship to the availability of higher education. Accordingly, studies made of college students almost always indicate higher statures than noncollege individuals. Yet, within the same group, variations in body size are so significant that “averages” are not necessarily meaningful or sufficient. To all this must be added such other considerations as the actual physical conditions under which data are recorded. Was the subject clothed or nude? If clothed, was the clothing light or heavy? Was the subject barefooted?
Figure 1-3. Bar graphs showing mean height and weight for U.S. children 6 to 11 years by annual family income and education of parents. Data from National Health Survey.
Although there have been some national and international attempts at standardization among anthropometrists, with regard to terminology and definitions, the lack thereof very often complicates the interpretation and significance of the data recorded. Studies, therefore, must often include descriptions of techniques used and diagrams necessary to clearly define the actual points from which measurements were taken. There is no doubt that anthropometric studies are no less sophisticated or tedious than other investigations in the biological sciences. When one considers that the anthropometrist must also be knowledgeable in the area of statistical methodology, the complexity and tediousness of the discipline is underscored even more. It is also obvious that those individuals taking and recording body measurements must be properly trained.
To the interior designer, architect, and industrial designer, however, it should be evident that the same factors that contribute to the complexity and tediousness of the discipline of anthropometry also necessitate a very cautious approach in the application of the data generated. It is essential, therefore, that the designer have some understanding of anthropometrics, its basic vocabulary, the nature of the data available, the forms in which it is usually presented, and the restraints involved in their application.