ISO/TS 16976-2:2010

TECHNICAL ISO/TS
SPECIFICATION 16976-2
First edition
2010-06-15

Respiratory protective devices — Human
factors —
Part 2:
Anthropometrics
Appareils de protection respiratoire — Facteurs humains —
Partie 2: Anthropométrie




Reference number
ISO/TS 16976-2:2010(E)
©
ISO 2010

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ISO/TS 16976-2:2010(E)
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ISO/TS 16976-2:2010(E)
Contents Page
Foreword .iv
Introduction.v
1 Scope.1
2 Normative references.1
3 Terms and definitions .1
4 Anthropometric measurements .1
4.1 Anthropometric instrument and software.1
4.2 Measurement procedures.2
4.3 Dimensions to be measured .2
5 Anthropometric data for head, face and neck dimensions.3
6 Anthropometric data for torso dimensions .5
7 Interface between headform and torso .6
8 Human test panels for facial features .7
8.1 General .7
8.2 Bivariate panel .7
8.3 Principal component analysis (PCA) panel .8
9 Models of headforms .11
Annex A (normative) Description, definition, and diagrams of selected landmarks.14
Annex B (normative) Description, definition, and diagram of dimensions to be measured.17
Annex C (informative) Examples of application of human test panels for facial features .20
Bibliography.24

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ISO/TS 16976-2:2010(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies
(ISO member bodies). The work of preparing International Standards is normally carried out through ISO
technical committees. Each member body interested in a subject for which a technical committee has been
established has the right to be represented on that committee. International organizations, governmental and
non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the
International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
In other circumstances, particularly when there is an urgent market requirement for such documents, a
technical committee may decide to publish other types of document:
⎯ an ISO Publicly Available Specification (ISO/PAS) represents an agreement between technical experts in
an ISO working group and is accepted for publication if it is approved by more than 50 % of the members
of the parent committee casting a vote;
⎯ an ISO Technical Specification (ISO/TS) represents an agreement between the members of a technical
committee and is accepted for publication if it is approved by 2/3 of the members of the committee casting
a vote.
An ISO/PAS or ISO/TS is reviewed after three years in order to decide whether it will be confirmed for a
further three years, revised to become an International Standard, or withdrawn. If the ISO/PAS or ISO/TS is
confirmed, it is reviewed again after a further three years, at which time it must either be transformed into an
International Standard or be withdrawn.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO shall not be held responsible for identifying any or all such patent rights.
ISO/TS 16976-2 was prepared by Technical Committee ISO/TC 94, Personal safety — Protective clothing and
equipment, Subcommittee SC 15, Respiratory protective devices.
ISO/TS 16976 consists of the following parts, under the general title Respiratory protective devices — Human
factors:
⎯ Part 1: Metabolic rates and respiratory flow rates [Technical Specification]
⎯ Part 2: Anthropometrics [Technical Specification]
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ISO/TS 16976-2:2010(E)
Introduction
For an appropriate design, selection and use of respiratory protective devices, basic physiological demands of
the user must be considered. Type and intensity of work affect the metabolic rate (energy expenditure) of the
wearer. Weight and weight distribution of the device on the human body can also influence metabolic rate.
Metabolic rate is directly correlated with oxygen consumption, which determines the respiratory demands and
flow rates. The work of breathing is influenced by the air flow resistances of the device and the lung airways.
The work (or energy cost) of a breath is related to the pressure gradient created by the breathing muscles and
the volume that is moved in and out of the lung during the breath. Anthropometric and biomechanical data are
required for appropriate design of various components of a respiratory protective device as well as for the
design of relevant test methods.
This technical specification forms Part 2 of a series of documents providing basic anthropometric
measurement methods and data on humans. It contains information about the description, definition and
diagram of landmarks and dimensions, up-to-date head and face data for various race/ethnic groups, and
human test panels.

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TECHNICAL SPECIFICATION ISO/TS 16976-2:2010(E)

Respiratory protective devices — Human factors —
Part 2:
Anthropometrics
1 Scope
This part of ISO/TS 16976 is one part of a series of technical specifications that provide information on factors
related to human anthropometry, physiology, ergonomics and performance for the preparation of standards for
design, testing and use of respiratory protective devices. This part of ISO/TS 16976 contains information
related to anthropometry. In particular, information is given for:
⎯ anthropometric measurement methods;
⎯ anthropometric data for head, face and neck dimensions;
⎯ anthropometric data for torso dimensions;
⎯ human test panels;
⎯ models of headforms.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated
references, only the edition cited applies. For undated references, the latest edition of the referenced
document (including any amendments) applies.
EN 14143, Respiratory equipment — Self-contained re-breathing diving apparatus
3 Terms and definitions
For the purposes of this document, the terms and definitions given in Annexes A and B apply.
4 Anthropometric measurements
4.1 Anthropometric instrument and software
The standard measurement tools which are recommended are the anthropometer, a spreading calliper, a
sliding calliper, a pupillometer, and a steel measuring tape. A suitable data entry, editing and analysis
[3][4]
software is described by Zhuang et al. .
4.1.1 Anthropometer, a specialized tool for measuring linear distance between points on the body and
standard reference surfaces, such as the floor or a seat platform.
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ISO/TS 16976-2:2010(E)
4.1.2 Spreading and sliding callipers, used for measuring the breadth and depth of body segments, as
well as the distance between reference marks.
4.1.3 Measuring tape, used for measuring the arc and circumference of body segments.
4.1.4 Pupillometer, a standard ophthalmic device used for measuring the interpupillary distance.
4.2 Measurement procedures
4.2.1 Landmarking
Landmarks are generally, although not always, skeletal points that are usually marked on the skin overlying
the point. Selected landmarks are listed in Table 1 and described in Annex A. Subjects are landmarked with a
surgical marker or an eyeliner pencil prior to measurement.
4.2.2 Measuring
After landmarking, subjects are measured for each of the dimensions. Data are recorded on data sheets and
simultaneously entered into computer software. The data entry and editing software evaluate each
measurement as it is entered, and indicate when a measurement value is out of the previously measured
range, or is otherwise unexpected. In such cases, the measurement shall be repeated or data input errors
corrected.
4.3 Dimensions to be measured
The dimensions to be measured are listed in Table 2. The detailed dimension descriptions are provided in
Annex B. All dimensions are measured in milimetres and body weight is measured in kilograms.
Table 1 — List of landmarks
Landmarks Landmark positioning
Alare Right and left
Cheilion Right and left
Chin —
Ectocanthus Right and left
Frontotemporale Right and left
Glabella —
Gonion Right and left
Infraorbitale Right and left
Menton —
Nasal root point Right and left
Pronasale —
Pupil Right and left
Sellion —
Subnasale —
Top of head —
Tragion Right and left
Zygion Right and left
Zygofrontale Right and left

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ISO/TS 16976-2:2010(E)
Table 2 — List of face dimensions
Dimensions Common terms
Bigonial breadth Jaw width
Bitragion chin arc
Bitragion coronal arc
Bitragion frontal arc
Bitragion subnasale arc
Bizygomatic breadth Face width
Head breadth
Head circumference
Head length
Interpupillary distance
Lip length
Maximum frontal breadth
Menton-sellion length Face length
Minimum frontal breadth
Nasal root breadth
Neck circumference
Nose breadth
Nose protrusion
Subnasale-sellion length Nose length
Stature Height
Weight

5 Anthropometric data for head, face and neck dimensions
Test panels for the development of an International Standard must be representative of the world population.
An anthropometric study of the US work population was conducted by the National Institute for Occupational
Safety and Health (NIOSH) in 2003. See Reference [3]. The survey consisted of three age strata (18 years to
29 years, 30 years to 44 years, 45 years to 66 years), two gender strata (male and female), and four
racial/ethnic group strata (white, African American, Hispanic and other). The selected test panel could be seen
as almost representative for the worldwide population, since the US population is multi-ethnic. Height, weight,
19 face dimensions and neck circumferences were measured using traditional methods. A total of 3 997
subjects (2 543 male and 1 454 female) were measured. The sampling strategy called for equal
representation in each of the sampling cells. This was done to ensure that we had adequately captured the
anthropometric variability in all segments of the population. NIOSH research has resulted in the development
of Table 3.
The NIOSH data were supplemented with additional measurements in China and other data for various
countries. See References [5] and [6]. The data were compared to the NIOSH US Data and were found to be
within the 5th and 95th percentiles for US population in Table 3.
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ISO/TS 16976-2:2010(E)
Table 3 — Anthropometric data for head, face, and neck dimensions by gender
(weight in kilograms, all other values in millimetres)
Males
Standard Percentiles
Dimension Number Mean Min. Max.
deviation
5th 50th 95th
Bigonial breadth 2 543 120,4 10,4 90 160 105 120 140
Bitragion chin arc 2 543 331,2 15,5 271 393 306 330 355
Bitragion coronal arc 2 543 350,7 13,9 310 405 330 350 375
Bitragion frontal arc 2 543 304,1 13,0 263 349 282 305 326
Bitragion subnasale arc 2 543 294,8 13,2 253 345 275 295 315
Bizygomatic breadth 2 543 143,5 6,9 120 170 132 143 155
Head breadth 2 543 153,0 6,0 135 179 144 153 163
Head circumference 2 543 575,7 17,1 520 639 547 575 604
Head length 2 543 197,3 7,4 174 225 185 197 210
Interpupillary distance 2 543 64,5 3,6 53 79 59 65 71
Lip length 2 543 51,1 4,2 40 70 44 51 58
Maximum frontal breadth 2 543 112,3 5,5 95 131 104 112 122
Menton-sellion length 2 543 122,7 7,0 100 156 111 123 135
Minimum frontal breadth 2 543 105,5 5,7 90 127 95 105 115
Nasal root breadth 2 543 16,6 2,3 10 29 13 16 20
Neck circumference 1 023 406,7 32,6 312 570 355 403 465
Nose breadth 2 543 36,6 4,1 26 58 31 36 45
Nose protrusion 2 543 21,1 2,7 13 32 17 21 26
Stature 2 543 1 753,9 67,7 1 488 2 012 1 642 1 754 1 866
Subnasale-sellion length 2 543 52,0 4,1 40 66 45 52 59
Weight 2 540 90,4 17,5 42,9 167,8 65,7 88,4 122,7

Females
Percentiles
Standard
Dimension Number Mean Min. Max.
deviation
5th 50th 95th
Bigonial breadth 1 454 110,1 8,9 88 150 98 110 125
Bitragion chin arc 1 454 303,9 14,9 248 375 280 305 328
Bitragion coronal arc 1 454 339,3 15,0 290 425 315 340 365
Bitragion frontal arc 1 454 287,4 11,9 250 330 270 287 305
Bitragion subnasale arc 1 454 277,5 13,1 238 335 258 277 300
Bizygomatic breadth 1 454 135,1 6,5 115 157 124 135 146
Head breadth 1 454 146,8 5,6 129 165 137 146 156
Head circumference 1 454 554,9 17,8 475 654 527 555 585
Head length 1 454 187,5 7,2 152 215 175 187 199
Interpupillary distance 1 452 61,9 3,5 52 78 56 62 68
Lip length 1 454 48,0 4,0 35 63 42 48 55
Maximum frontal breadth 1 454 108,6 5,3 92 130 100 108 117
Menton-sellion length 1 454 113,4 6,1 91 135 104 113 124
Minimum frontal breadth 1 454 102,9 5,4 84 126 94 103 111
Nasal root breadth 1 454 16,3 2,0 10 25 13 16 20
Neck circumference 793 339,5 30,9 260 505 295 335 395
Nose breadth 1 454 33,2 3,9 22 54 28 33 41
Nose protrusion 1 454 19,8 2,7 11 29 16 20 25
Stature 1 454 1 625,4 67,5 1 310 1 862 1 513 1 627 1 731
Subnasale-sellion length 1 454 48,2 3,8 32 59 42 48 55
Weight 1 454 75,7 18,7 34,2 176,4 51,8 72,1 112,1
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ISO/TS 16976-2:2010(E)
6 Anthropometric data for torso dimensions
The application for the torso to be developed is to hold an RPD (respiratory protective device) designed to be
worn on the human body, in position, during testing. The data given for this torso are not appropriate for use in
the design of the RPD. Since there will be no test where ergonomic features are checked by using the torso, it
[7]
has been agreed to use the ADULTDATA handbook mean values of males and females. A subset of the
ADULTDATA including anthropometric data for a number of surveys from UK, Sweden, Italy, France, China,
Japan and USA was used.
The mean values of the designated measurements identifying the main dimensions of a torso illustrated in
Figure 1 are listed in Table 4. The measure reference identification numbers have been taken from the
ADULTDATA handbook as they are numbered originally to allow comparison.
The last column in Table 4 shows the mean for male and female mean data which leads to the neutral
dimension to be taken for modelling of the torso.
The torso is positioned on an elliptical contoured platform with the axis a = 200 mm, b = 300 mm and a
minimum height of 150 mm. This generates some space for parts of an RPD extending beyond the torso, but
which are not in contact with the plateau, whichever way the torso is placed. The RPD will be fixed to the torso
by the harness without touching the plateau.
The torso will have a socket at the top for inserting the headforms described in this part of ISO/TS 16976.
Table 4 — Mean anthropometric data for torso dimensions by gender and combined population
ADULTDATA
Dimension Dimension Dimension
measure
50 % 50 % 50 %
Description
reference
male female mean
identification
number mm mm mm
51 Height of prominent neck vertebra, sitting 667 628 648
55 Shoulder breadth (deltoid) 458 416 437
59 Shoulder (acromion) height, sitting 605 569 587
61 Mid-shoulder height, sitting 632 579 606
64 Chest breadth, at level of nipples 329 282 306
66 Chest circumference, at level of nipples 916 921 919
68 Chest depth, at level of nipples 248 251 250
72 Trunk height to the top of breast bone, sitting 597 573 585
73 Lower abdominal depth 284 250 267
74 Waist breadth 259 264 262
75 Waist circumference – natural indentation 839 769 804
82 Height of maximum lumbar curvature, sitting 241 232 237
83 Sacral height, sitting 162 159 161
84 Hip breadth 327 321 324
87 Mid-hip circumference 1 060 1 056 1 058
NOTE Measure reference numbers are taken from ADULTDATA handbook dimensions.

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ISO/TS 16976-2:2010(E)
Dimension in millimetres

Key
1 socket for headform
B top of breast bone
a
All numbers are reference numbers in accordance with Table 4.
Figure 1 — Torso contour given by measure references
7 Interface between headform and torso
The torso described in this part of ISO/TS 16976 will be able to carry the five different headforms by a socket
at the top. In order to test the RPD in its operational position, the headforms will be used to connect the RPD
with the breathing machine/simulator whilst fixed to the torso. The headform will have a fixed position in
relation to the torso by using reference points (A and B) which are illustrated in Figures 1 and 2. The reference
for all headforms is the point A, the centre of the mouth opening. This point will be positioned always 165 mm
above the top of the breast bone (point B) as defined by measure reference number 72 of the torso contour.
The length of the headform necks have to be designed accordingly. This relation is based on the information
given in EN 14143.
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ISO/TS 16976-2:2010(E)
Dimension in millimetres

Key
A centre of the mouth opening
B top of breast bone, according to measure 72 of Table 4
a
All numbers are reference numbers in accordance with Table 4.
Figure 2 — Interface between head and torso
8 Human test panels for facial features
8.1 General
This clause shows how collected anthropometric data are used to develop human test panels; see
Reference [4]. Two such panels are described.
8.2 Bivariate panel
The human test panel based on face length and face width is shown in Figure 3. This panel covers 96,7 % of
males and 98,7 % of females of the selected population. This panel has limits of 98,5 mm to 138,5 mm for
face length and 120,5 mm to 158,5 mm for face width. These limits were first based on the male mean plus
two standard deviations (SDs) and the female mean minus two SDs. Cell boundaries were then adjusted so
that the population can be distributed among cells as uniformly as possible. The boundaries were set so that
at least 95 % of the population was included in the panel. See also Annex C.
The standards writers can use this bivariate panel, the composition of which will be representative of target
populations. A test panel shall use a minimum of ten subjects with at least one subject from each of the cells
representing the target population.
In Figure 3, the cells are numbered from 1 to 10. When the subject's face length or face width falls on the
boundaries, the subject is classified into the higher number cells with greater face dimensions.
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ISO/TS 16976-2:2010(E)

Key
X face width in millimetres
Y face length in millimetres
Figure 3 — Bivariate panel based on face length and face width
8.3 Principal component analysis (PCA) panel
The human test panel based on the PCA scores is shown in Figure 4. This panel covers 95,3 % of the males
and 97,6 % of the females of the selected population. The layout of cells is different from the bivariate panel.
The limit of this panel is based on an ellipse in which more than 95 % of the population is included. The inner
ellipse includes 50 % of the population. The rationale for the rest of the PCA configuration is to have uniform
distributions for each cell. Thus, two lines were used to divide the two ellipses into four quadrants resulting in
eight cells. The population is then uniformly distributed among the cells.
The standards writers can use this PCA panel, the composition of which will be representative of target
populations. A test panel shall use a minimum of ten subjects with at least one subject from each of the cells
representing the target population.
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ISO/TS 16976-2:2010(E)

a)  The PCA panel based on two principal components with cells numbered from 1 to 8
Key
X first principal component
Y second principal component


b)  The PCA panel based on two principal components with cells numbered from 1 to 4
Key
1 major axis
2 minor axis
Figure 4
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ISO/TS 16976-2:2010(E)
To construct the PCA panel, the ten face dimensions or the 18 face dimensions (see Table 2), as measured in
millimetres in accordance with Clause 4 and Annex B, are entered into the following algorithm. The first and
second principal components (PC1 and PC2) are then calculated as follows.
PC1 =
0,343 264 × (minimum frontal breadth A) + 0,426 498*(face width B) + 0,372 717 × (bigonial breadth C) +
0,329 648 × (menton sellion length D) + 0,363 474 × (interpupillary distance E) + 0,372 241 ×
(head breadth F) + 0,113 578 × (nose protrusion G) + 0,301 125 × (nose breadth H) + 0,202 311 ×
(nasal root breadth J) + 0,193 650 × (subnasale-sellion length K)
PC2 =
−0,152 951 × (minimum frontal breadth A) + 0,039 087 × (face width B) − 0,093 279 × (bigonial breadth C)
0,359 799 × (menton sellion length D) + 0,173 099 × (interpupillary distance E) + 0,013 306 ×
(head breadth F) + 0,551 842 × (nose protrusion G) + 0,210 833 × (nose breadth H) + 0,341 235 ×
(nasal root breadth J) + 0,584 261 × (subnasale-sellion length K)
Then make the following calculations:
x = PC1 − 281,621 761 8
y = PC2 − 28,986 505 4
slope = 5,584 793 0/13,699 110 8 = 0,407 675 6
a = 2,54 × 13,699 110 8
b = 2,54 × 5,584 793 0
c = 1,21 × 13,699 110 8
d = 1,21 × 5,584 793 0
22
xy
r=+
1
22
ab
22
xy
r=+
2
22
cd
where
x and y are new coordinates for translating the origin of PC1 and PC2 from their mean values
(281,621 761 8 for PC1 and 28,986 505 4 for PC2) to zero;
slope is the slope value for the two lines dividing the ellipse into eight cells;
a is a constant for the length of the semi-major axis for the outer ellipse (see the illustration
below);
b is the constant for the length of the semi-minor axis for the outer ellipse (see the illustration
below);
c is a constant for the length of the semi-major axis for the inner ellipse;
d is the constant for the length of the semi-minor axis for the inner ellipse;
r and r are values calculated to determine where a particular data point or a subject is, e.g. the data
1 2
point is outside the outer ellipse when r > 1 or on the outer ellipse when r = 1 or inside the
1 1
outer ellipse when r < 1.
1
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ISO/TS 16976-2:2010(E)
Use the x, y and r values and the algorithm below to determine if the subject is in cells 1, 3, 6 and 8:
1
if x W 0 and y W 0 and r u 1 and abs(y)/abs(x) u slope, then cell = 8;
1
if x W 0 and y < 0 and r u 1 and abs(y)/abs(x) < slope, then cell = 8;
1
if x W 0 and y < 0 and r u 1 and abs(y)/abs(x) W slope, then cell = 3;
1
if x < 0 and y < 0 and r u 1 and abs(y)/abs(x) > slope, then cell = 3;
1
if x < 0 and y < 0 and r u 1 and abs(y)/abs(x) u slope, then cell = 1;
1
if x < 0 and y W 0 and r u 1 and abs(y)/abs(x) < slope, then cell = 1;
1
if x < 0 and y W 0 and r u 1 and abs(y)/abs(x) W slope, then cell = 6;
1
if x W 0 and y W 0 and r u 1 and abs(y)/abs(x) > slope, then cell = 6.
1
If the r value u 1, use the following algorithm to adjust the cell number:
2
if cell = 8 and r u 1, then cell = 7;
2
if cell = 3 and r u 1, then cell = 4;
2
if cell = 1 and r u 1, then cell = 2;
2
if cell = 6 and r u 1, then cell = 5.
2
The measurement of these ten dimensions is described in Annex B. A test panel member should be
remeasured when the member has a condition that may interfere with the respirator seal, e.g. a significant
change in weight, a change to the face in the sealing area (e.g. scarring, facial surgery) or dental changes.
NOTE A video tape (see Reference [8]) is available which demonstrates the landmarking and measuring techniques
with the traditional tools. A computer program (see Reference [9]) is available which provides a tool for recording
measurements and determining the cell number for each subject.
9 Models of headforms
This clause shows how collected anthropometric data are used to develop models of headforms. Based on
the PCA panel, five models of headforms are developed [10]. Four models (small, short/wide, long/narrow and
large) represent subjects in cells 1, 3, 6 and 8 respectively (see Figure 4). Subjects in cells 2, 4, 5, and 7 are
represented by one model (medium). Figure 5 shows the distribution of the five headforms. The key
dimensions (i.e. the ten facial dimensions used for defining the PCA panel) for each model are obtained by
averaging the values for the subjects each model represents, including subjects who fall outside the PCA
panel (all five models represent a total of 3 997 subjects) and are summarised in Table 5.
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ISO/TS 16976-2:2010(E)

Key
1 long-narrow
2 large
3 short-wide
4 small
5 medium
Figure 5 — Distribution of the five headforms
Table 5 — Mean values for key facial dimensions of headforms
Dimensions in millimetres
Headform Headform Headform Headform Headform
Facial article cell 1 cell 3 cells 2, 4, 5, 7 cell 6 cell 8
(small) (short/wide) (medium) (long/narrow) (large)
A Minimum frontal breadth 98 106 104 103 110
B Face width 128 141 140 140 151
C Bigonial breadth 101 118 115
...