Table 1. Selection of body dimensions to be measured for classroom furniture design.
S/NO. According to ISO 7250
Basic students’ body dimensions
Description according to ISO 7250-1:2017
6.1.2
Stature (body height)
The vertical distance from the floor to the highest
point of the head (vertex).
6.2.1
Sitting height (erect)
The vertical distance from a horizontal sitting
surface to the highest point of the head (vertex).
6.2.4
Shoulder height, sitting
The vertical distance from a horizontal sitting
surface to the acromion.
6.2.11
Popliteal height, sitting
The vertical distance from the foot-rest surface to
the lower surface of the thigh immediately behind
the knee, bent at right angles.
6.2.10
Hip breadth, sitting
The breadth of the body measured across the widest
portion of the hips.
6.2.5
Elbow height, sitting
The vertical distance from a horizontal sitting surface to the lowest bony point of the elbow bent at
a right angle with the forearm horizontal.
6.4.7
Buttock popliteal length (seat depth)
The horizontal distance from the hollow of the knee
to the rearmost point of the buttock.
6.4.8
Buttock knee length
The horizontal distance from the foremost point of
the knee-cap to the rearmost point of the buttock.
6.2.12
Thigh clearance
The vertical distance from the sitting surface to the
highest point on the thigh.
6.2.2
Eye height, sitting
The vertical distance from a horizontal sitting
surface to the outer corner of the eye (ectocanthus).
6.2.8
Shoulder (bideltoid) breadth
The horizontal distance across the maximum lateral
protrusions of the right and left deltoid muscles.
6.2.13
Knee height, sitting
The vertical distance from the floor to the highest point of the superior border of the patella
(suprapatella, sitting).
6.1.1
Body mass
The total mass (weight) of the body.
6.4.6
Forearm fingertip length
The horizontal distance from olecranon (back of
the elbow) to the tip of the middle finger, with the
elbow bent at right angles.
Source: (Esmaeel & Order 2017).
4 RESULTS AND DISCUSSION
4.1 Anthropometric dimension for students
The results obtained from the four selected tertiary institutions were analysed using Minitab 17.0
statistical package, to get the mean, standard deviation,
5th, 50th, and 95th percentiles. For seat height, the 5th
percentile (lower percentile) of the popliteal height
of the population is usually recommended so that a
larger number of the population is accommodated, thus
allowing a short person to use the chair. Similarly, the
95th percentile (larger percentile) of the hip breadth is
usually recommended in the design of the seat width
to accommodate as many people of the population as
possible, thus allowing an overweight person to use
the chair. The following results, shown in Table 2, give
a summary of the anthropometric measures, based on
the average of the collected anthropometric data, that
can be used in designing a desktop–chair for students
at four selected tertiary institutions in Uasin-Gishu
County, Kenya.
After analysing all the anthropometric measurements of the students at the four selected tertiary
institutions, the final specification is proposed for
the design of the ergonomic desktop–chair that
Table 2. Summary of anthropometric dimension for student of the selected institutions (n = 382).
St.
5th
50th
95th
Variable
Mean Dev Percentile percentile Percentile
Age (Yrs.)
20.51 1.67 18.00
20.00
23.00
Stature
168.38 7.86 155.50
168.00
182.00
Sitting height
81.01 4.01 75.00
81.80
88.00
Shoulder
height
54.41 2.76 50.96
54.50
57.80
Popliteal
height
44.73 2.78 40.50
44.50
49.60
Hip breadth
33.46 3.49 29.57
32.86
39.36
Elbow height
20.39 1.16 19.11
20.30
22.37
Buttock
popliteal
length
42.54 2.73 38.10
42.65
46.90
Buttock knee
length
51.85 3.05 47.20
51.90
56.70
Thigh
clearance
14.54 1.70 11.96
14.43
17.39
Eye height
67.43 3.46 62.88
68.00
72.50
Shoulder
breadth
41.78 3.43 37.02
41.47
46.59
Knee height
51.96 3.29 46.80
52.10
57.30
Body mass
60.54 9.09 48.00
59.50
75.50
Forearm
fingertip
length
47.62 2.70 43.46
47.44
51.88
41
S/NO. According to ISO 7250
Basic students’ body dimensions
Description according to ISO 7250-1:2017
6.1.2
Stature (body height)
The vertical distance from the floor to the highest
point of the head (vertex).
6.2.1
Sitting height (erect)
The vertical distance from a horizontal sitting
surface to the highest point of the head (vertex).
6.2.4
Shoulder height, sitting
The vertical distance from a horizontal sitting
surface to the acromion.
6.2.11
Popliteal height, sitting
The vertical distance from the foot-rest surface to
the lower surface of the thigh immediately behind
the knee, bent at right angles.
6.2.10
Hip breadth, sitting
The breadth of the body measured across the widest
portion of the hips.
6.2.5
Elbow height, sitting
The vertical distance from a horizontal sitting surface to the lowest bony point of the elbow bent at
a right angle with the forearm horizontal.
6.4.7
Buttock popliteal length (seat depth)
The horizontal distance from the hollow of the knee
to the rearmost point of the buttock.
6.4.8
Buttock knee length
The horizontal distance from the foremost point of
the knee-cap to the rearmost point of the buttock.
6.2.12
Thigh clearance
The vertical distance from the sitting surface to the
highest point on the thigh.
6.2.2
Eye height, sitting
The vertical distance from a horizontal sitting
surface to the outer corner of the eye (ectocanthus).
6.2.8
Shoulder (bideltoid) breadth
The horizontal distance across the maximum lateral
protrusions of the right and left deltoid muscles.
6.2.13
Knee height, sitting
The vertical distance from the floor to the highest point of the superior border of the patella
(suprapatella, sitting).
6.1.1
Body mass
The total mass (weight) of the body.
6.4.6
Forearm fingertip length
The horizontal distance from olecranon (back of
the elbow) to the tip of the middle finger, with the
elbow bent at right angles.
Source: (Esmaeel & Order 2017).
4 RESULTS AND DISCUSSION
4.1 Anthropometric dimension for students
The results obtained from the four selected tertiary institutions were analysed using Minitab 17.0
statistical package, to get the mean, standard deviation,
5th, 50th, and 95th percentiles. For seat height, the 5th
percentile (lower percentile) of the popliteal height
of the population is usually recommended so that a
larger number of the population is accommodated, thus
allowing a short person to use the chair. Similarly, the
95th percentile (larger percentile) of the hip breadth is
usually recommended in the design of the seat width
to accommodate as many people of the population as
possible, thus allowing an overweight person to use
the chair. The following results, shown in Table 2, give
a summary of the anthropometric measures, based on
the average of the collected anthropometric data, that
can be used in designing a desktop–chair for students
at four selected tertiary institutions in Uasin-Gishu
County, Kenya.
After analysing all the anthropometric measurements of the students at the four selected tertiary
institutions, the final specification is proposed for
the design of the ergonomic desktop–chair that
Table 2. Summary of anthropometric dimension for student of the selected institutions (n = 382).
St.
5th
50th
95th
Variable
Mean Dev Percentile percentile Percentile
Age (Yrs.)
20.51 1.67 18.00
20.00
23.00
Stature
168.38 7.86 155.50
168.00
182.00
Sitting height
81.01 4.01 75.00
81.80
88.00
Shoulder
height
54.41 2.76 50.96
54.50
57.80
Popliteal
height
44.73 2.78 40.50
44.50
49.60
Hip breadth
33.46 3.49 29.57
32.86
39.36
Elbow height
20.39 1.16 19.11
20.30
22.37
Buttock
popliteal
length
42.54 2.73 38.10
42.65
46.90
Buttock knee
length
51.85 3.05 47.20
51.90
56.70
Thigh
clearance
14.54 1.70 11.96
14.43
17.39
Eye height
67.43 3.46 62.88
68.00
72.50
Shoulder
breadth
41.78 3.43 37.02
41.47
46.59
Knee height
51.96 3.29 46.80
52.10
57.30
Body mass
60.54 9.09 48.00
59.50
75.50
Forearm
fingertip
length
47.62 2.70 43.46
47.44
51.88
41