Lab Practice HFE (INP 559)
Name : Siddhant Binani
2019-2020
Roll No: 77
Evaluation Sheet
Sr.
No.
Title of Experiment
1
To conduct the Illumination and Noise level assessment of a
workplace.
2
Determination of Body Mass Index (BMI), and Calculations of
Basal Metabolic Rate (BMR) and Resting Metabolic Rate (RMR)
for Physiological Workload Calculation.
3
Determination of Physiological Cost of Walking and Physiological
Cost Index of walking (PCI) Using Heart Rate.
4
Determination of Anthropometric dimensions for Workplace
Design
5
Case Study
Date of
Conduction
Total Marks
(10)
Prof. Himanshu M. Shukla
Course Coordinator
Lab Manual (Human Factors Engineering)
EXPERIMENT NO: 1
Aim – To conduct the Illumination and Noise level assessment of a workplace.
Requirement- LUXMETER, NOISE LEVEL METER
Measurement of Illumination:
Illumination means light. The type of illuminations are natural (Sun) and artificial (Tube light,
bulbs etc.). The design of artificial illumination system does have an impact on the
performance and comfort of those using the environment as well as on the effective
response of the people to the environment. Illumination engineering is both an art and a
science. The scientific aspects include the measurement of various lighting parameters and
the design of energy-efficient lighting system.
Measurement of light:
There are many concepts and terms related to measurement of light (photometry).
The fundamental photometric quantity is luminous flux, which is the rate at which light
energy is emitted from a source. The unit of luminous flux is lumen (lm). Luminous flux is a
somewhat esoteric concept, which is similar to other flow rates such as gallons per minute.
Time is implied in the unit of luminous flux. The luminous intensity of a light source is
measured in lumens emitted by the source per unit solid angle. The unit of luminous
intensity is candela (cd). A 1-cd source emits 12.57 lm.
Consider a source of some luminous intensity emitting luminous flux in all directions;
imagine the source as being placed inside a sphere. The amount of light striking any point on
the inside surface of the sphere is called illumination, or Illuminance. It is measured in terms
of luminous flux per unit area, as for example lumens per sq. foot or lumens per sq. meter.
One lumen per sq foot is called footcandle (fc), a USCS unit, where one lumen per sq. meter
is called lux (lx), a SI unit.
One footcandle equals 10.76lx.
The amount of illumination striking a source from a point source follows the inverse-square
law:
Illuminance (lx) = candlepower (cd)/ D2
Where D is the distance from the source in meters.
The amount of light per unit area is leaving a surface is called luminance. The light leaving
the surface may be reflected by the surface or emitted by the surface would occur with a
fluorescent light panel. The amount of light can be measured in luminance flux (lumens) or
luminous intensity (candelas). When the light is measured in lumens and the area in sq.
meters, the S.I. units of luminance is candela per sq meter.
The ratio of the amount of light (luminous flux) reflected by the surface (luminance) to the
amount of light striking the surface (Illuminance) is called the reflectance.
In SI units
Reflectance = π x luminance (cd/m2)/ Illuminance (lx)
In USCS units is Reflectance = luminance (fL)/ Illuminance (fc)
Reflectance is expressed as unitless proportion.
Department of Industrial Engineering, RCOEM Nagpur
Lab Manual (Human Factors Engineering)
Luminaries:
Luminaries are classified into five categories based on the proportion of light (lumens)
emitted above and below the horizontal. In selecting a particular type of luminaries for use,
consideration for use, consideration must be given to the pattern of light distribution, glare,
task illumination, and shadowing and energy efficiency. Various
Devices can be incorporated into a luminaries to control the distribution of light, including
lenses, diffusers, shielding, and reflectors. Choice of efficient luminaries is complex decision,
should be made by, and qualifies, experienced person after an analysis of the lighting needs
and the physical environment has been made.
How much is enough?
The problem of determining the level of illumination that should be provided for various
visual task can be done via many a methods i.e. Blackwell etc.
The IES provides the tables for the measurement of safe and appropriate illumination be as
follows. Recommended illumination levels for use in interior lighting design:
Category Ranges of
luminance, Lx
A
20-30-50
B
50-75-100
C
100-150-200
D
200-300-500
E
500-750-1000
F
1000-1500-2000
G
2000-3000-5000
H
5000-700010000
10000-1500020000
I
Type of activity
Public areas with dark surroundings.
Simple orientation for short temporary visits.
Working spaces where visuals tasks are performed only
occasionally.
Performance of visual tasks of high contrast or large size:
Eg. reading printed material, typed originals, handwriting
in ink, food xerography, machine work, ordinary
inspection.
Performance of visual tasks of medium contrast or small
size; eg: reading medium pencil handwriting, poorly
printed or reproduced material; medium bench and,
machine work; difficult inspection; medium assembly
Performance of visual tasks of low contrast or very small
size; eg., reading handwriting in hard pencil on poor
quality paper and very poorly reproduced material; highly
difficult inspection
Performance of visual tasks of low contrast and very small
size over very prolonged period; eg, fine assembly, very
difficult inspection, fine bench and machine work
Performance of very prolonged and exacting visual tasks;
eg inspection; extra fine bench and machine work;
Performance of very special visual tasks of extremely low
contrast and small size; eg; surgical procedures
Department of Industrial Engineering, RCOEM Nagpur
Lab Manual (Human Factors Engineering)
Observation Sheet:
Illumination Assessment
Date of Audit: 26/7/22
Time: 3 PM
SN
Place
Illumination
Location
(lx)
1
Lathe
2
Carpentry
3
Smithy
4
Moulding
5
Campus
Tailstock
Chuck
Switch
Drives
Bench wise
Table
Side Bench wise
Anvil
Moulding Area
Shelf
Notice board diagram
Construction
Washroom
Playing Area
Gym
34
45
77
25
43
60
60
26
560
20
210
28000
20
31000
900
Measurement of Noise Level: Loudness is a subjective or psychological experience related to both the intensity and the
frequency of sound. Researchers have tried to develop scales indices based on the physical
properties of sound that will measure the psychological experience, hence the term
psychological. Among the oldest and most widely recognized psychological indices of
loudness are the phon and sone.
Examples of Loudness levels:
Noise Source
Residential inside, quite
Household ventilating fan
Automobiles, 50 ft(15 m)
‘ Quiet ‘ Factory Area
18-in (46-cm) automatic lathe
Punch press, 3ft (1m)
Nail-making machines, 6ft (2m)
Pneumatic riveter, 4ft(1.2 m)
Loudness
Decibels
42
56
68
76
89
103
111
128
Sones
1
7
14
54
127
350
800
3000
OSHA (Occupational safety and Health administration) standards:
The OSHA limits for noise exposure are as shown below:
Duration
dBA
Department of Industrial Engineering, RCOEM Nagpur
Lab Manual (Human Factors Engineering)
8 Hours
4 Hours
1 Hours
25 Min
90
95
105
115
OSHA noise exposure limits
In typical situations, hearing loss is perhaps the prime criterion for acceptable noise levels.
Standards that differentiate between continuous noise, impulse noise, infrasonic noise, and
ultrasonic noise, have been set by various organizations.
Continuous and intermittent noise
OSHA has established, permissible noise exposures for persons working on jobs in industry.
The permissible levels depend on the duration of exposure were shown in the above table.
A key concept in the OSHA requirements is noise dose. Exposures to any sound level at or
above 80 dBA causes the listener to incur a partial dose of noise. The partial dose is
calculated for each specified sound pressure level above 80 dBA as follows:
[Time actually spent at sound level]/[maximum permissible time at sound level]
Noise dose is a total exposure to any sound above 80 dBA during 8-h day.
D = 100 x (C1/T1 + C2/T2+……Cn/Tn)
<= 100%
Where d=noise dose during 8-h day
Ci=hours spent at given noise level.
Ti=hours spent at noise level.
The total or daily noise dose is equal to the sum of the partial doses. The noise dose can
there be converted to an 8-h time weighted average (TWA) sound level. The TWA is the
sound level that would produce a given noise dose if an employee were exposed to that
sound level continuously over an 8-h workday.
A noise dose of 50% (TWA= 85 dBA) is designated as the action level, or the point at which
the employer must implement a continuing, effective hearing conversation program. The
program must include exposure monitoring, audiometric testing, hearing protection,
employee training, and record keeping. A noise dose of 100% TWA = 90 dBA is designated as
the permissible exposure level, or the point at which the employee must use the feasible
engineering and administrative controls to reduce noise exposure.
Noise Dose
10
25
50 (action level)
75
100 (permissible exposure level)
115
130
150
175
TWA,(16.61log(0.01D)+90)dBA
73
80
85
88
90
91
92
93
94
Department of Industrial Engineering, RCOEM Nagpur
Lab Manual (Human Factors Engineering)
200
400
95
100
Department of Industrial Engineering, RCOEM Nagpur
Lab Manual (Human Factors Engineering)
Noise Level Assessment
SN
1
Date of Audit: 26/07/2022
Time: 2:00 PM
Noise
Place
Location
(dBA)
Workshop
2
Campus
3
Canteen
4
Reading
Room
Lathe
Smithy
Construction
Area
Classroom
IT Square
IT Parking
Gym
Table
Counter
69
91
85
88
80.7
82
Table
95
Remark
101
95
72
All the places are prone to
high level of sound
CONCLUSION:
Using daylight as much as possible reduces the energy input of artificial lighting required in the
industry halls. Daylighting should be designed in such a way that glare is reduced. According to
the results of the model, glare was observed on both types of glazing and under both types of sky
conditions. By using diffuse glazing, however, the brightness values were smaller. However, the
diffuse glazing was considered in the alternative only for the skylight and not for the side
windows and therefore it would be appropriate to consider the visual comfort for this alternative
in the future.
According to the results obtained in this study, by increasing the sound pressure level,
performances and errors are definitely affected. At the sound pressure level of 95 dB, the
efficiency decreased and rate of mistakes increased, and in exposure to sounds less than 85 dB at
the initial period, performance increased and with the passage of time of confrontation, the
performance gradually reduced.
Date of Performance: 26/7/2022
Name of Course Coordinator: Prof. Himanshu Shukla
Grade
Signature:
Department of Industrial Engineering, RCOEM Nagpur
Experiment No:- 02
Date:- 31/08/2022
Aim – Determination of Body Mass Index (BMI), and Calculations of Basal Metabolic
Rate (BMR) and Resting Metabolic Rate (RMR)
Requirement: Stadometer, Weighing Machine
Theory of Experiment
Body mass index is defined as the individual's body weight divided by the square of
their height. The formulas universally used in medicine produce a unit of measure of kg/m 2.
Body mass index may be accurately calculated.
BMI range:
Starvation
Category
BMI
range kg/m2
BMI Chart:
Underweight Normal
less than 15
from 15 to from
18.5
18.5
25
Overweight Obese
Morbidly
Obese
from 25 to from 30 greater
to 30
to 40
than 40
Aim – Determination of Body Mass Index (BMI), and Calculations of Basal Metabolic
Rate (BMR) and Resting Metabolic Rate (RMR)
Calculating BMR and RMR
BMR and RMR are estimates of how many calories you would burn if you were to do nothing
but rest for 24 hours. They represent the minimum amount of energy required to keep your
body functioning, including your heart beating, lungs breathing, and body temperature normal.
The Harris-Benedict equation for BMR (calories in 24 Hrs.):
For men: (13.75 x w) + (5 x h) - (6.76 x a) + 66
For women: (9.56 x w) + (1.85 x h) - (4.68 x a) + 655
The Muffling equation for RMR (calories in 24 Hrs.):
•
•
For men: (10 x w) + (6.25 x h) - (5 x a) + 5
For women: (10 x w) + (6.25 x h) - (5 x a) - 161
Where: w = weight in kg, h = height in cm, a = age years.
Observation Table:
BMI , BMR, RMR:
Data Recording Form
Date: 31/08/2021
Name: Aayush Bisani
Weight: 53 kg
Age: 21
Roll
No.
Name
Weight(in
Gender Age kg)
Height(in
cm)
BMI
BMR
RMR
166.37 17.16103893 1318.6045 1248.8125
1 Arpita Aparajit
Female
21
47.5
2 Aryaa Joshi
Female
20
45
3 Ayushi Lanke
Female
20
62
156.5 25.31412998 1443.645 1337.125
4 Bhavisha Agrawal
Female
21
57.5
157.5 23.17964223 1397.795 1293.375
5 Divya Vyawahare
Female
21
64
174 21.13885586
1490.46 1461.5
6 Himanshee Dixit
Female
20
52.5
152.4 22.60421188
1345.24 1216.5
7 Mitali Agrawal
Female
21
44
150 19.55555556
1254.86 1111.5
11 Aayush Bisani
Male
21
53
180.34 16.29640236
12 Abdul Razique
Male
20
51
175 16.65306122
1507.05 1508.75
13 Abhijit S Rajurkar
Male
21
82
183 24.48565201
1966.54 1863.75
15 Aditya Jain
Male
20
73
187 20.8756327
1869.55 1803.75
16 Akshansh Jaiswal
Male
22
82
175 26.7755102
1919.78 1808.75
17 Akshat Kotadia
Male
21
65
173 21.71806609
1682.79 1631.25
18 Aman Kumar
male
21
98
188 27.7274785
2211.54 2055
20 Arya Khatri
male
22
85
185 24.83564646
2011.03 1901.25
21 Ayman Sheikh
Male
20
60
175 19.59183673
1630.8 1598.75
22 Ayush Agrawal
Male
21
55
177.4 17.47654013
1567.29 1558.75
24 Chetan Tawari
Male
21
64
174 21.13885586
1674.04 1627.5
Abdul Daniyal
29 Kazi
Male
21
60
182 18.11375438
1659.04 1637.5
30 Neusy Jain
Female
21
60
31 Rucha Toal
female
21
70
170 24.22145329
1736.54 1662.5
32 Sneha Tembhare
Female
21
54
156 22.18934911
1361.56 1249
33 Snehal Rathi
Female
21
59
162 22.48132907
1420.46 1336.5
34 Tanu Agrawal
Female
21
68
156 27.94214333
1495.4 1389
35 Tanushree Pal
Female
22
53
159 20.96436059
36 Vishakha Agrawal Female
21
43
164 15.98750744
150
20
1269.1 1126.5
1554.49 1557.125
170.18 20.71735041 1445.153 1397.625
1352.87 1252.75
1271.2 1189
Deepansh
41 Rughwani
Male
21
70
186 20.23355301
1816.54 1762.5
Mohd. Haris
42 Sheikh
Male
22
87
175 28.40816327
1988.53 1858.75
43 Rasika Palkar
Female
21
52
44 Harshal vyas
Male
21
74
177 23.62028791
1826.54 1746.25
45 Indra Gupta
Male
21
74
174 24.44180209
1811.54 1727.5
46 Jatin Pradhan
Male
21
65
174 21.46915048
1687.79 1637.5
47 Karn Agrawal
Male
21
62
170 21.4532872
1626.54 1582.5
48 Kartik Agrawal
Male
21
75
174 24.77209671
1825.29 1737.5
49 Krishna Chaturvedi male
21
75
186 21.6788068
1885.29 1812.5
165.1 19.07696123 1359.275 1285.875
Conclusion
Category
Underweight Normal
Overweight Obese
Starvation
BMI range less than
- kg/m2
15
from 15 to
18.5
Roll
No.
1
from 18.5 from 25 to
to 25
30
BMI
Shantanu
Kale
2
Yash
3
Aryan
4
Shreya
5
Ayush
6
Vidhi
7
Tejas
11
Siddhant
12
Sugam
13
Shantanu
Morbidly
Obese
from 30 greater
to 40
than 40
15
Arya
16
17
Kankshita
Mrunal
18
20
Jaskaran
Yashvi
Therefore, Determination of Body Mass Index (BMI), and Calculations of Basal Metabolic
Rate (BMR) and Resting Metabolic Rate (RMR) are done successfully with the help of given
theory and formulas.
Date of Performance: 31/08/2022
Name of Course Coordinator: Prof. Himanshu Shukla
Signature:
Grade
Experiment No: 3
Date: 28/09/22
Aim - Determination of Physiological Cost of Walking and Physiological Cost
Index of walking (PCI) Using Heart Rate
Requirement: Digital Pulse meter, Stethoscope, Measuring Tape, Stop Watch.
Theory of Experiment
Walking is an activity which has been studied by many investigators. The results indicate
that if the speed range is 3.2 Km/hr, energy expended is almost linearly proportional to speed of
walking. It has also been found that the more the body weight the greater is the energy
expenditure for the same speed of walking.
The relations established are as follows:
The Oxygen consumption = [-0.155 + 0.024 x Heart Rate (Beats/min)] l/min
Energy Consumption = 5 x Oxygen consumption kcal/min
The purpose of this study is to determine the variability of the physiological cost index
(PCI) for normal subjects performing two distinct gait tasks; free walking at their naturally
adopted speed and forced walking at a fixed cadence. Knowledge of the PCI variability is
important since this normalized index is often used to compare the walking efficiency of subjects
exhibiting gait pathology, or to determine if a particular therapeutic intervention affects overall
gait performance.
PCI is defined as the ratio of net heart rate to velocity in the units of beats/meter, where
net heart rate is the difference between average heart rate over a fixed distance and resting heart
rate while standing.
Parameters:
1. heart rate at rest in beats per minute
2. heart rate when walking in beats per minute
3. walking speed in meters per minute
PCI = ((heart rate when walking) - (heart rate at rest)) / (walking speed)
The results show that PCI is relatively invariant in successive passes for the same subject for
either free or forced walking, but quite variable for different type of walking speeds.
Interpretation:
• A low PCI indicates an energy-efficient gait.
10
PROCEDURES
Use one subject and follow the procedures outlined below:
1. The heart Rate at rest is measured.
2. The Weight of the subject is measured.
3. The subject is allowed to walk at Slow, Moderate, Fast speeds.
4. The readings of the Heart Beats of the subjects are recorded at different speeds till it
stabilizes to RMV (Resting Minute Ventilation) or BMR (Basal Metabolic Rate)
Observation Table:
Physiological Cost of Walking and PCI
Data Recording Form
Date: 28/09/21
Subject's Name: Amit T.
Subject's Weight: 95 kg
Heart Beats at Rest: 82 bpm
Sr.
No.
1
2
3
4
5
6
Distance,
m
42
83
49
98
74
139
Time,
minutes
1
2
1
2
1
2
Speed
Heart Rate
42
41.5
49
49
74
69.5
88
93
97
92
103
103
Subject's Name: Shankar M.
Subject's Weight: 56 kg
Heart Beats at Rest: 85 bpm
Sr.
No.
1
2
3
4
5
6
Distance,
m
48
95
60
128
72
150
Time,
minutes
1
2
1
2
1
2
Speed
Heart Rate
48
47.5
60
64
72
95
91
93
93
100
105
114
Subject's Name: Dev B.
Subject's Weight: 78 kg
Heart Beats at Rest: 68 bpm
Sr.
No.
1
2
3
Distance,
m
47
103
68
Time,
minutes
1
2
1
Speed
Heart Rate
48
55
68
70
72
85
11
4
5
6
130
77
160
2
1
2
65
77
80
86
96
102
Calculations:
Sr. No.
HR
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
70
72
85
86
88
91
92
93
93
93
96
97
100
102
103
103
105
114
Oxygen
consumption
1.525
1.573
1.885
1.909
1.957
2.029
2.053
2.077
2.077
2.077
2.149
2.173
2.245
2.293
2.317
2.317
2.365
2.581
Energy
Consumption
7.625
7.865
9.425
9.545
9.785
10.145
10.265
10.385
10.385
10.385
10.745
10.865
11.225
11.465
11.585
11.585
11.825
12.905
Calculation of PCI & Rest minutes requirements:
PCI = ((heart rate when walking) - (heart rate at rest)) / (walking speed)
PCI= (114-85)/95) = 0.305263 mins
Rest = T (K- S)/ (K-1.5)
where,
R = Rest required in minutes
T = Total work time in minutes
S = Recommended average expenditure in Kcal/min (usually taken as 4 to 5 Kcal/min)
K = Energy expenditure Kcal/minutes
Rest = T (K- 5)/ (K-1.5) minutes = (9*(12.905-5)/ (12.905-1.5)) = 6.238053 minutes
12
CONCLUSION: Therefore, Determination of Physiological Cost of Walking and Physiological
Cost Index of walking (PCI) Using Heart Rate is successfully calculated.
Date of Performance: 28/09/22
Name of Course Coordinator: Prof. Himanshu Shukla
Grade
Signature:
13
Experiment 4
Aim: Determination of Anthropometric dimensions for Work place Design
Theory:
Anthropometry (Greek, man, and, measure, literally meaning "measurement of humans"), in
physical anthropology, refers to the measurement of living human individuals for the purposes
of understanding human physical variation.
Today, anthropometry plays an important role in industrial design, clothing design,
ergonomics and architecture where statistical data about the distribution of body dimensions in
the population are used to optimize products. Changes in life styles, nutrition and ethnic
composition of populations lead to changes in the distribution of body dimensions (e.g., the
obesity epidemic), and require regular updating of anthropometric data collections. The
comfort, physical health, well-being, and performance of people can be increased by designing
equipment, goods, furniture, and other devices according to the needs of the human body.
When designing for people we have to consider their measurements and since everyone
is different we have to use averages. Males in turn have different overall measurements than
women so two sets of data are needed. If we were designing for a child the measurements
would be considerably smaller and if we were designing for a basketball team the needs would
be different again. Usually when information is collected the extremes (very tall, very small
very fat, very thin, are ignored because they give a false end result. Below are average
measurements of men and women with the bottom 5% ignored and the top 5% ignored.
These measurements might help you in your designing.
Percentiles Percentiles are shown in anthropometry tables and they tell you whether the
measurement given in the tables relates to the 'average' person, or someone who is above or
below average in a certain dimension.
If you look at the heights of a group of adults, you'll probably notice that most of them look
about the same height. A few may be noticeably taller and a few may be noticeably shorter.
This 'same height' will be near the average (called the 'mean' in statistics) and is shown in
anthropometry tables as the fiftieth percentile, often written as '50th %ile'. This means that it
is the most likely height in a group of people. If we plotted a graph of the heights (or most
other dimensions) of our group of people, it would look similar to this:
First, notice that the graph is symmetrical – so that 50% of people are of average height or
taller, and 50% are of average height or smaller. The graph tails off to either end, because fewer
people are extremely tall or very short. To the left of the average, there is a point known as the
5th percentile, because 5% of the people (or 1 person in 20) is shorter than this particular height.
The same distance to the right is a point known as the 95th percentile, where only 1 person in
20 is taller than this height. So, we also need to know whether we are designing for all potential
users or just the ones of above or below average dimensions. Now, this depends on exactly
what it is that we are designing.
For example, if we were designing a doorway using the height, shoulder width, hip width etc.,
of an average person, then half the people using the doorway would be taller than the average,
and half would be wider. Since the tallest people are not necessarily the widest, more than half
the users would have to bend down or turn sideways to get through the doorway. Therefore, in
this case we would need to design using dimensions of the widest and tallest people to ensure
that everyone could walk through normally.
Deciding whether to use the 5th, 50th or 95th percentile value depends on what you are
designing and who you are designing it for. Usually, you will find that if you pick the right
percentile, 95% of people will be able to use your design. For instance, if you were choosing a
door height, you would choose the dimension of people's height (often called 'stature' in
anthropometry tables) and pick the 95th percentile value – in other words, you would design
for the taller people. You wouldn't need to worry about the average height people, or the 5th
percentile ones – they would be able to fit through the door anyway.
At the other end of the scale, if you were designing an aero plane cockpit, and needed to make
sure everyone could reach a particular control, you would choose 5th percentile arm length –
because the people with the short arms are the ones who are most challenging to design for. If
they could reach the control, everyone else (with longer arms) would be able to.
Here are some examples of other situations - your design project will normally fit into one of
these groups:
What is it that
you are aiming
for with your
design?
Design examples:
Examples of
measurements to
consider:
Users that your
design should
accommodate:
Vehicle dashboards,
Shelving
Arm length,
Shoulder height
Smallest user: 5th
percentile
Adequate clearance Manholes,
to avoid unwanted Cinema seats
contact or trapping
Shoulder or hip width,
Thigh length
Largest user: 95th
percentile
A good match
between the user
and the product
Knee-floor height, Head Maximum range:
circumference, Weight 5th to 95th
percentile
Easy reach
Seats,
Cycle helmets,
Pushchairs
A comfortable and Lawnmowers,
safe posture
Monitor positions,
Worksurface heights
Elbow height,
Maximum range:
Sitting eye height,
5th to 95th
Elbow height (sitting or percentile
standing?)
Easy operation
Screw bottle tops,
Door handles,
Light switches
Grip strength,
Hand width,
Height
To ensure that an
item can't be
reached or
operated
Machine guarding mesh, Finger width
Distance of railings from
hazard
Arm length
Smallest or
weakest user: 5th
percentile
Smallest user: 5th
percentile
Largest user: 95th
percentile
Sometimes you can't accommodate all your users because there are conflicting solutions to
your design. In this case, you will have to make a judgment about what is the most important
feature. You must never compromise safety though, and if there is a real risk of injury, you
may have to use more extreme percentiles (1%ile or 99%ile or more) to make sure that
everyone is protected.
You may need to add corrections for clothing. Have you allowed for shoe heights? You
generally add 20mm for fairly flat shoes, and more if you think users will be wearing high
heels. If your product is to be used somewhere cold, can it still be used if someone is wearing
gloves or other bulky clothing?
Figure showing major anthropometric dimensions:
Table showing Sample Observations:
We are not conducting the experiment because offline classes are not being conducted due to
Covid-19 pandemic. Therefore, I have attached a literature review of a research paper on the
same topic.
Topic: An Ergonomic Approach on Facilities and Workstation Design of Public School
Canteen in the Philippines by Ma. Janice J. Gumasing, Eidref Joseph E. Espejo
Abstract:
This paper aims to redesign the facilities and workstations of public school canteen in the
Philippines by applying the principles of Ergonomics. Previous studies have proven that
workers in the canteen are exposed to musculoskeletal disorders and injuries due poor facility
layout and workstation design. Thus, the researchers aim to assess the current condition of the
public school canteen in the Philippines in order to determine the risk and exposure of the
workers to musculoskeletal disorders (MSD) and injuries. The researchers also aim to identify
significant factors in the design of canteen that affect the discomfort level of workers in terms
of the following: personal factor, physical factors and task-related factor. Result of rapid entire
body assessment (REBA) and NIOSH lifting equation proved that workers are exposed to risk
of MSD. The researchers redesigned the facilities and workstation of public school canteen by
applying the principles of ergonomics, quality function deployment (QFD) and systematic
layout planning (SLP) tools.
Summary:
The researchers conducted the study among the six (6) public schools in Metro Manila wherein
large numbers of students and staff were located. A total of 42 respondents were involved in
the study. The researchers have conducted review of related literature, direct observation,
surveys, interview and actual measurement of tools and materials used by canteen staff.
Devices such as BP meter, light meter, noise dosimeter, and digital psychrometer were used to
obtain demographic profile factors of the respondents as well as measures for environmental
factors. The researchers also used Cornell Musculoskeletal Disorder Questionnaire (CMDQ)
in order to determine the discomfort location and common types of musculoskeletal disorders
experienced by canteen staff when performing their tasks. Postural analysis was also done in
order to gather data for task related factors. The researchers used Rapid Entire Body
Assessment (REBA) to evaluate whole body postural MSD and measure risks associated with
the task of canteen staff. NIOSH lifting equation was also used to assess the manual material
handling risks of workers associated with lifting and lowering tasks in their job.
Based on the results, the most affected body parts of workers in terms of discomfort and MSD
when performing their tasks are the following: neck, upper back, shoulders, lower back,
hips/buttocks, upper arm and lower leg. The researchers also assessed the lifting posture of
canteen staff using NIOSH Lifting Equation. The job resulted in poor lifting conditions
specifically on the task of lifting of water from the floor. The results of the analyses have proven
the need for the redesign of facilities and workstation for public school canteen. Therefore, the
researchers used the principles of anthropometry to ensure that the design will match the body
dimensions of users in order to improve their comfort, health, safety and productivity. In order
to redesign the facilities of public school canteen in order to improve the efficiency and
productivity of workers, the researchers used systematic layout planning. And in order to
determine the arrangement of activities in the work area in a systematic manner, the researchers
developed a relationship chart and diagram for each public school canteen considered in the
study.
Conclusion:
The findings of the study have proven that workers in canteen are exposed to risks of
musculoskeletal disorders and injuries due to poor facility and workstation design. The risk
was evident on the scores generated by RULA and NIOSH computed from their body postures
while performing tasks. Based on the result of CMDQ, majority of the respondents’ experience
pain on their neck, upper back, shoulders, lower back, hips/buttocks, upper arm and lower leg.
Several risk factors were considered in the study based on review of related literature, direct
observation and interview from the people involved in the tasks. Factors considered are the
following (1) personal factor: age, gender, height, weight, BMI, (2) environmental factor:
temperature, illumination, noise, (3) task-related factors: rest period, work duration, work
posture and lifting posture. These factors were analysed and treated using regression analysis.
The result revealed that factors such height, body-mass index, temperature, lifting posture, and
work posture significantly affect the risk and exposure of workers to MSD. Given these
conditions, the researchers were able to redesign the facilities and workstation of public school
canteen by applying the principles of ergonomics, quality function deployment (QFD) and
systematic layout planning (SLP) tools.
Date of Performance: 26/7/2022
Name of Course Coordinator: Prof. Himanshu Shukla
Signature:
Grade