ergo-online academy copyright 2008 ergo-online, llc 1 anthropometrics
TRANSCRIPT
Ergo-Online Academy
Copyright 2008 Ergo-Online, LLC
4
Ergonomics The Science of Error Reduction
When possible try to design out the chance of error.
Ergo-Online Academy
Copyright 2008 Ergo-Online, LLC
5
Anthropometrics
• Human Measurements• Heights, Reaches,
Clearance• Gender Strength
Differences• Postural Strength
Differences
Ergo-Online Academy
Copyright 2008 Ergo-Online, LLC
6
Design so the large can fit, the small can reach and the weak can lift, lower, push, pull & carry.
Anthropometrics
Ergo-Online Academy
Copyright 2008 Ergo-Online, LLC
9
Anthropometric DataDimension 5th 50th 95th
Male Female Male Female Male Female
Standing Vertical Grip Reach 76.8 71.1 81.9 75.8 87.0 80.5
Standing Forward Grip Reach 28.5 25.8 30.9 28.0 33.3 30.1
Height 64.6 59.8 69.1 64.0 73.6 68.1
Eye Height 62.8 55.9 67.3 60.0 71.9 64.2
Shoulder Height 52.4 48.2 56.7 52.2 61.0 56.1
Elbow Height 40.2 37.2 43.5 40.2 46.9 43.1
Sitting Vertical Grip Reach 45.5 42.1 49.4 45.7 53.4 49.2
Sitting Height 33.7 31.5 36.0 33.9 38.4 36.2
Sitting Eye Height 29.1 27.2 31.5 29.5 33.9 31.9
Sitting Elbow Height 7.7 7.3 9.7 9.3 11.6 11.2
Adapted from: Pheasant, Stephen, (1996). “Bodyspace: Anthropometry, Ergonomics and the Design of Work”, Bristol, PA: Taylor & Francis.
Ergo-Online Academy
Copyright 2008 Ergo-Online, LLC
10
Things To Consider• Determine what body dimensions are relevant.• Determine what population group is relevant.• Use the anthropometric data as a guide and a
place to start. It does not replace employee input.
• Just because something does not fall within anthropometric guidelines does not mean it is a significant ergonomic risk.
• When designing workstations or equipment, you will never be able to accommodate everyone. You try to accommodate as much of the population as you can, given the space and cost parameters you have to work within.
Ergo-Online Academy
Copyright 2008 Ergo-Online, LLC
11
General Design Guidelines
• Standing Working Heights
• Sitting Working Heights
• Reaches• Gender Strength
Differences• Postural Strength
Differences
Ergo-Online Academy
Copyright 2008 Ergo-Online, LLC
16
Sagittal Reach Envelopes
• Avoid reaching above shoulder or behind the body.
Ergo-Online Academy
Copyright 2008 Ergo-Online, LLC
17
Strength Variability Between Males & Females
Body Part Percent
Arms 60 %
Trunk 64%
Legs 72%
Ergo-Online Academy
Copyright 2008 Ergo-Online, LLC
18
Male Grip Strength
Male (lbs)
Percentiles 18 - 29 30 - 39 40 - 49 50 - 59 60 - 69 70 - 79
5 75.2 88.0 84.4 78.3 70.5 -
25 93.7 101.2 97.7 93.7 82.5 70.1
50 110.9 112.0 108.0 102.5 90.4 80.5
75 123.5 124.6 121.3 112.4 100.3 88.4
95 144.0 144.6 134.5 132.1 113.5 100.5
Mean 110.2 113.8 109.0 102.1 90.6 76.9
Adapted from: Australian Fitness Norms, 1992, The Health Development Foundation, Adelaide, p.32.
Ergo-Online Academy
Copyright 2008 Ergo-Online, LLC
19
Female Grip Strength
Female (lbs)
Percentiles 18 - 29 30 - 39 40 - 49 50 - 59 60 - 69 70 - 79
5 52.0 49.6 49.6 40.8 38.6 -
25 62.8 61.7 59.5 54.0 50.3 47.6
50 66.8 68.3 66.1 63.9 55.1 55.1
75 75.0 76.1 72.8 70.5 61.7 59.5
95 85.5 88.2 83.8 78.3 74.7 67.2
Mean 68.0 69.0 66.4 61.3 55.6 51.4
Adapted from: Australian Fitness Norms, 1992, The Health Development Foundation, Adelaide, p.32.
Ergo-Online Academy
Copyright 2008 Ergo-Online, LLC
20
Anthropometrics and Tool Design
• Grip strength as a function of the handle span takes anthropometric data into consideration.
• The optimal separation is 45 to 55 mm.
Ergo-Online Academy
Copyright 2008 Ergo-Online, LLC
22
Arm Cranking Strength and Postural Variability
Ergo-Online Academy
Copyright 2008 Ergo-Online, LLC
24
Maximum Force Exerted In Seated Position at Various Elbow Angles
Movement 60 deg 90 deg 120 deg 150 deg 180 deg
Pull 28.6 40.0 47.3 55.5 54.5
Push 41.8 39.1 46.8 55.9 62.7
Right 19.1 16.8 15.5 15.0 15.5
Left 23.6 22.7 24.1 24.5 22.7
Up 22.3 25.5 27.3 25.5 19.5
Down 23.2 24.1 26.4 21.4 18.6
Ergo-Online Academy
Copyright 2008 Ergo-Online, LLC
25
Ear-Eye-Line
• The EE line is determined by using the ear-hole and the junction of the eyelids. The EE line describes the posture of the head and serves as reference for the angle of the line of sight.
Ergo-Online Academy
Copyright 2008 Ergo-Online, LLC
26
Line of Sight
• The line of sight connects the pupil with the visual target. Eye movement within about 15 degrees above and below the average line-of-sight angle is still comfortable.
Ergo-Online Academy
Copyright 2008 Ergo-Online, LLC
27
Choosing Working Postures
• Sitting – For accurate control, fine
manipulation.– For continuous light
manipulation work.– For close visual work
with prolonged attention.– For limited headroom,
low work heights.
Ergo-Online Academy
Copyright 2008 Ergo-Online, LLC
28
• Standing– For heavy, bulky loads– When frequent
movement is required– When there is no knee
room under the equipment
– Where there is limited front-rear space
Choosing Working Postures
Ergo-Online Academy
Copyright 2008 Ergo-Online, LLC
29
Designing Lifting Tasks
• Lifting zones are based upon anthropometric data
Ergo-Online Academy
Copyright 2008 Ergo-Online, LLC
30
Cost-Benefit Function• Anthropometric cost-benefit function showing
the percentage of members of a target population accommodated by various ranges of seat height adjustment.