A HEAD-AND-FACE ANTHROPOMETRIC SURVEY - The National ...

Other statistics can be calculated in the same way. Of course it is not necessary to do
these calculations by hand. Most statistical packages have a weighting feature, since
this is a standard technique, and the user simply indicates which variable is the
weighting variable, and the requested statistics are calculated using the weighted
values.
Following the calculation of the weights, we calculated the basic summary statistics for
each measured dimension. The summary statistics are shown in Table 8, for males
and females, separately. In most cases, work force populations are not evenly split
between the sexes. This is certainly true in the subpopulation that wears respirators.
For example, users in the health professions tend to be mostly female. Those in
construction tend to be mostly male. Fire and police are largely male, and so on.
Therefore it would be inappropriate for a designer or tester of respirators to use
combined sex data, since either the males or the females for a particular application
would not be fit well. It is better to develop and test respirators for males and females
separately. A given work group can order appropriate numbers of each size based on
the specific population at that location.
In order to show a snapshot of the facial anthropometry of the total U.S. population
aged 18 to 66, we have included Table 9. As noted above, in most cases, the statistics
in this table should not be used for respirator design, since most respirators are not
used by men and women equally.
It is interesting to see how these population data differ from military data. In the Army’s
1987-1988 anthropometric survey, ANSUR, (Gordon et al., 1989), a number of these
same dimensions were collected using the same measurement techniques. The mean
and standard deviations for selected dimensions are shown in Table 10.
For this comparison, the Army data have been weighted to match the current U.S.
civilian work force, using the same techniques described above.
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