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Evaluation on discomfort level among students using desks in classrooms

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This study was conducted to evaluate the discomfort level among students using desks in classrooms of Polytechnic Kuching. The students (n=500) completed the questionnaire survey form using Borg’s CR-10 Scale showing body chart discomfort. The students was asked to identify their body areas experiencing discomfort and to rate this discomfort on a score rating groups (0 to 5). Score 0-1.99 = No discomfort (1), score 2.00-3.99 = Discomfort (2) and score 4.00-5.00 = Very uncomfortable (3). The evaluation of the seating shows discomfort level of students and any outstanding problems arising. Students were asked to rank in the order of 10 statements about comfort and choose three responses which gave the most consistent equal interval scale. The results in that the main response of discomfort indicated the students mostly agree that they are feeling from cramped, stiff, numb, sore and tender to unbearable pain, barely comfortable and feel uncomfortable. The project was identified to evaluate the comfort level of classrooms desks for polytechnic students. Overall, there was a significant discomfort level for the students whilst using the desks and a possible solution put forward is to design a new type of classroom desk made of natural fibre reinforced composite.
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Jurnal
Teknologi
Full Paper
EVALUATION ON DISCOMFORT LEVEL AMONG
STUDENTS USING DESKS IN CLASSROOMS
Mahmood Alia,e* , Mohd Sapuan Salita,b, Karmegam Karuppiahc,
Abu Saleh Ahmedd
aLaboratory of Biocomposite Technology, Institute of Tropical
Forestry and Forest Products, Universiti Putra Malaysia, 43400 UPM
Serdang, Selangor, Malaysia.
bDepartment of Mechanical and Manufacturing Engineering,
Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia.
cDepartment of Environmental and Occupational Health, Faculty
of Medicine and Health Sciences, Universiti Putra Malaysia, 43400
UPM Serdang, Selangor, Malaysia.
dDepartment of Mechanical and Manufacturing Engineering,
Universiti Malaysia Sarawak, 94300 Kota Samarahan, Sarawak,
Malaysia.
eDepartment of Mechanical Engineering, Polytechnic Kuching
Sarawak, KM.22, Jalan Matang, 93050 Kuching Sarawak.
Article history
Graphical abstract
Abstract
This study was conducted to evaluate the discomfort level among students using desks in
classrooms of Polytechnic Kuching. The students (n=500) completed the questionnaire
survey form using Borg’s CR-10 Scale showing body chart discomfort. The students was
asked to identify their body areas experiencing discomfort and to rate this discomfort on
a score rating groups (0 to 5). Score 0-1.99 = No discomfort (1), score 2.00-3.99 = Discomfort
(2) and score 4.00-5.00 = Very uncomfortable (3). The evaluation of the seating shows
discomfort level of students and any outstanding problems arising. Students were asked to
rank in the order of 10 statements about comfort and choose three responses which gave
the most consistent equal interval scale. The results in that the main response of discomfort
indicated the students mostly agree that they are feeling from cramped, stiff, numb, sore
and tender to unbearable pain, barely comfortable and feel uncomfortable. The project
was identified to evaluate the comfort level of classrooms desks for polytechnic students.
Overall, there was a significant discomfort level for the students whilst using the desks and
a possible solution put forward is to design a new type of classroom desk made of natural
fibre reinforced composite.
Keywords: Evaluate comfort level, Classroom desks, Polytechnic students.
Abstrak
Kajian ini dijalankan untuk menilai tahap ketidakselesaan di kalangan pelajar
menggunakan meja di dalam kelas Pengajian Politeknik Kuching. Pelajar-pelajar (n = 500)
melengkapkan bentuk soal selidik menggunakan Borg CR-10 Skala menunjukkan badan
rasa tidak selesa carta. Pelajar-pelajar telah diminta untuk mengenal pasti bidang badan
ketidakselesaan mengalami mereka dan untuk mengadar ketidakselesaan ini pada
kumpulan Kedudukan skor (0-5). Skor 0-1,99 = Tiada rasa tidak selesa (1), skor 2,00-3,99 =
Ketidakselesaan (2) dan skor 4,00-5,00 = Sangat tidak selesa (3). Penilaian duduk
menunjukkan tahap ketidakselesaan pelajar dan sebarang masalah yang timbul. Pelajar
diminta untuk pangkat dalam perintah 10 kenyataan tentang keselesaan dan pilih tiga
128 Mahmood Ali et al. / Jurnal Teknologi (Sciences & Engineering) 77:27 (2015) 127134
jawapan yang memberikan skala selang sama yang paling konsisten. Keputusan dalam
bahawa sambutan utama rasa tidak selesa yang ditunjukkan pelajar sebahagian besar
bersetuju bahawa mereka berasa dari sempit, kaku, kebas, sakit dan tender kepada
kesakitan yang tidak tertanggung, hampir tidak selesa dan berasa tidak selesa. Projek ini
telah dikenal pasti untuk menilai meja tahap keselesaan ofclassrooms untuk pelajar
politeknik. Secara keseluruhan, terdapat satu tahap ketidakselesaan penting bagi pelajar
menggunakan meja dan satu cara penyelesaian yang dikemukakan adalah untuk
mereka bentuk jenis baru meja kelas diperbuat daripada serat semula jadi komposit
bertetulang.
Kata kunci: Menilai tahap keselesaan, Meja kelas, Pelajar Politeknik
© 2015 Penerbit UTM Press. All rights reserved
1.0 INTRODUCTION
Chairs and desks have become an important element
of the teaching and learning process. Chairs and
desks are widely used in the classroom for the students
of Polytechnic Kuching Sarawak [1]. Students remain
seated at their desks for a considerable amount of
time. Correct standing and sitting posture is an
important factor for the prevention of musculoskeletal
symptoms and an incorrect sitting or standing posture
will put an extreme physiological strain on the muscles
[2]. Taking this into consideration, as well as the
potential incorrect use of polytechnic furniture, it is
likely that some anatomical-functional changes and
problems in the teaching learning process may occur.
This situation could be a potential catalyst for the study
and development of a new design of polytechnic
furniture suitable to the needs of the students and
utilizing the appropriate dimensions according to the
student’s anthropometrics characteristics [3].
Ergonomics is the study that aims to design an
efficient work environment for workers and students
alike, so that they can carry out their work or studies
easily, effectively and safely [4]. The use of
appropriately developed designed furniture may lead
to reduced fatigue and discomfort in the sitting
posture [5]. The anthropometric dimensions needed to
determine polytechnic furniture dimensions that can
promote a correct sitting posture include popliteal
height, knee height, buttock popliteal length and
elbow height [6].
The term comfort and discomfort in an ergonomic
scope is generally used in scientific literature to
highlight problems related to the seating condition [7].
However, this term has been also used to evaluate the
comfort and discomfort among the students1.
Relatively the existence of comfort and discomfort on
students’ body parts can be related to the design and
development of new adjustable chairs and desks with
the aforementioned functions which are essential for
maintaining good posture which promotes better
learning [8].
Classroom furniture is meant to provide
comfortable support to students during classroom
activities which includes when writing on the table.
There can be a variety of comfortable furniture where
different furniture in different zones and places can be
used together or separately to cater to the needs of
types of users/students [9]. When designing classroom
furniture, student’s ease of mobility should be
considered since localized muscle fatigue could set in
due to prolonged immobility. Actual chair and desk
dimensions are determined by measurements of the
human body or anthropometric measurements since
anthropometric statistics may be used for mass
produced furniture and designs are usually made
based on these statistics [10]. Previous studies
conducted have recommended that an
anthropometric survey is needed to determine the
design dimensions of educational furniture for
polytechnic students [1].
Wood is a valuable natural renewable resource
that has helped countries lead sustainable
development over countries. Wood-composite-
manufacturing industries are in constant search for
new sources of fibers as raw materials to be used in
their production; therefore, potential natural or
synthetic fiber should be taken into account as the
raw materials needed for uninterrupted production
[11].
However natural fiber does have advantages over
synthetic fibers which are low cost, good specific
mechanical strength, low density, good thermal and
insulating properties and it causes no harm to the
environment [12, 13].
This study is of particular interest as it concerns
polytechnic students rather than younger children as
reported in most previous studies in Malaysia and
elsewhere. However, there hasn’t been any research
that has been undertaken to evaluate the comfort
and discomfort levels among students during their
learning process. Therefore, this study was undertaken
in order to highlight the comfort and discomfort levels
of the students whilst being seated. The objective of
this study was to determine the overall discomfort
score of students sitting in front of the desk, to identify
the discomfort symptoms on which parts of their body
whilst sitting in classroom and to identify the statistically
significant differences on discomfort score among the
male and female students.
129 Mahmood Ali et al. / Jurnal Teknologi (Sciences & Engineering) 77:27 (2015) 127134
2.0 METHODOLOGY
2.1 Study Model
This is a survey study conducted through quantitative
analysis aimed at determining the discomfort level of
students sitting in front of their desks and the
comparison of body symptoms among the male and
female students.
2.2 Population And Sample Of The Study
The students in Polytechnic Kuching, Sarawak,
Malaysia were selected to be the population of this
study. The students were selected randomly from the
polytechnic students’ database system. A total of
4,395 students were registered with this polytechnic in
June 2014 session. A total 213 males and 287 female
students were randomly selected as sample size for
this study. This total of students is deemed as an
appropriate sample size for this study based on
previous studies14. For the purpose of this study, the
students that have history of musculoskeletal disorder
problems were excluded from this study.
The selected students were called in for a briefing
session at the beginning of this study. The students
were informed on the aim and objective of this study.
They were also informed that this is a voluntary basis
study and they have the option to pull out from this
study if they need or wish to. The survey forms were
distributed to the students at the beginning. The
students were request to return the forms after 10
minutes (end). 10 minute duration was given so that
the students could provide an effective answer to the
required questions in the survey form.
In the end, the return ratio of the surveys was 100%.
A total of 500 complete survey forms from the students
were collected.
2.3 The Data Collection Instrument
A survey method was used to collect data within the
scope of the study. There were two parts in the survey
questionnaire. The first part was to determine the
personal information of the students who participated
in the study. In the second part, previous research
works [15,16,17,18] were adapted with the aim of
determining the symptoms of discomforts level of the
students. It consists of a discomfort checklist
questionnaire in the form of a body chart (Figure 1).
The score rating of each discomfort symptom was
carried out according to the checklist.
In order to determine its validity, the questionnaire
was submitted to the experts in the field and
necessary revision was done based on their feedback.
The revised questionnaire was tested on a small
research group. The value of coefficient of Cronbach
alpha was examined in order to test the reliability of
the survey. The analysis revealed that the alpha value
of 20 items as 0.934. When the coefficient of alpha is
between 0.80 and 1.00, which means that it is highly
reliable. The latest revised questionnaire was then
used to collect data from the selected student’s
population.
3.0 RESULTS AND DISCUSSION
Before analyzing the data, the returned
questionnaires were checked individually. The
questionnaires that were not answered properly and
those that reported of having history of
musculoskeletal disorder diseases were excluded from
this study. A total of 500 (100%) completed and valid
questionnaires were returned by the respondents.
In order to determine the overall symptom of
discomforts, the average arithmetic total score (on
both left and right sides of the body) given by the
students were calculated (total score III in Figure 1).
The average arithmetic score distributions (total scores
I and II in Figure 1) of the discomfort level experienced
by students on parts of their body were also
calculated. The findings were then evaluated on the
following simplified score rating groups; score 0 to 1.99
Figure 1 The body chart discomfort checklist (adapted from previous studies) [15,16,17,19]
130 Mahmood Ali et al. / Jurnal Teknologi (Sciences & Engineering) 77:27 (2015) 127134
= No discomfort (1), score 2.00 to 3.99 = Discomfort (2)
and score 4.00 to 5.00 = Very uncomfortable (3).
In the analysis of the data, apart from the arithmetic
scores, independent t test for paired comparisons
were also applied. The significance level was
accepted as 0.05 in the analyses
3.1 Characteristics Of Respondent’s Students
Sitting In Front Of Desks (N=500)
Table 1 presents the characteristics of the respondents
sitting. A total of 213 male students and 287 female
students participated in this study. Their ages ranged
from 18 to 24 years. The value for uncomfortable score
rating groups was; score 4.00 to 5.00 = very
uncomfortable. For the male students, the mean for
shoulder was 4.43, upper back was 4.42, lower back
was 4.47 and buttock was 4.73 respectively for the
males. Meanwhile for the female students the mean
for shoulder was 4.43, upper back was 4.27, lower
back was 4.37 and buttock was 4.63. The means for
neck or head were 2.75 and 2.77 for the male and
female students respectively. The results of discomfort
level are presented in Table 1. The results also highlight
that the male and female students have reported
discomfort levels in most of their body.
Table 1 Characteristics of the respondent students sitting on chairs (n=500
3.2 Discomfort symptoms level by the students
Table 2 and Figure 2 highlight the overall score rating
of discomfort level by the male and female students.
The results indicate that more than 50% of the male
and female students of having very uncomfortable
level during the sitting process. It should also be noted
that there is a high percentage of 59.53% of male
students and 58.46% female student who have
reported of having very uncomfortable levels of
discomfort on their bodies. Meanwhile, 17.79% of male
students and 16.72% of female students have been
identified of having no discomfort in their body.
Figure 2 Score rating of student’s discomfort
131 Mahmood Ali et al. / Jurnal Teknologi (Sciences & Engineering) 77:27 (2015) 127134
3.3 Discomfort Rating Symptoms Level By The Students
The results of discomfort level by a total of 500 students
(213 males and 287 females) are presented in Table 3
and Figure 3. It represents the rating of discomfort level
on each parts of their body. The results indicate that
male and female students have a similar type of
discomfort level whilst sitting. The results also
highlighted that the male and female students have
reported discomfort levels in all parts of their body.
The male and female students have reported of
having discomfort level (score rating of 2) in the
shoulder, upper back, lower back and buttock (male:
0.00%; female: 0.00%) where the no value of score
rating (2) = level discomfort for the body part. The non-
discomfort level are identified by the score rating of 1.
The male and female students have identified thigh
(male: 30.98%; female: 25.43%), knee (male: 32.86%;
female: 31.707%) and calf leg below knee (male:
35.68%; female: 37.63%) as having the more
discomfort in parts of their body.
It is also important to highlight that higher percentage
of female students (37.63%) have reported to level
discomfort in the calf leg below knee compared to
male (35.68%). Meanwhile, 1.95% of male have been
reported of having less discomfort level in their calf leg
below knee compared to female (37.63%) students.
The score rating of 3 represents the most ‘very
uncomfortable’ symptoms for the students. The male
and female students have indicated that level the
most uncomfortable symptoms in their shoulder, upper
back, low back and buttock. A total of 100% of female
and 100%of male students have been reported of
having these uncomfortable levels in their shoulder.
Meanwhile, 100% of male and 100%female have
uncomfortable levels in their upper back. The male
and female students have identified lower back
(male: 100% and female: 100%) as having ‘very
uncomfortable’. The male and female students have
reported to have very uncomfortable level in the
buttocks as well (male: 100%; female: 100%).
Figure 3 Students discomfort symptom score rating
132 Mahmood Ali et al. / Jurnal Teknologi (Sciences & Engineering) 77:27 (2015) 127134
Table 3 Rating on discomforts symptoms by students (n=500)
3.4 Comparison Of Discomfort Symptoms Among
The Male And Female Students
The independent t-test was conducted in order to
determine whether there is a statistically significant
difference between male and female students with
regards to their reported discomfort level (Table 4).
The results indicate that there are a total of four
significance differences in the score rating of
discomfort levels between male and female students.
Significant differences were found in the shoulder,
upper back, lower back and buttock. The mean
discomfort scores of shoulder for male and female
students differed significantly (t=0.083, df=498, p<0.05)
with the male score being significantly higher than the
female mean
Similarly, the upper back discomfort score for male are
significantly higher than the female mean score with
significant differences (t=3.933, df=498, p<0.05)
between them.
The mean discomfort score for female on the lower
back and buttock are significantly higher than the
male mean score. The significant differences on the
lower back (t=0.039, df=498, p<0.01) and buttock
(t=0.333, df=498, p<0.01) was recorded for the male
and female students.
The findings in Table 4 also shows that there are no
significant differences in other male and female
student’s body parts such as neck or head, arm and
hand, thigh, knee, calf (leg below knee), ankle and
feet.
133 Mahmood Ali et al. / Jurnal Teknologi (Sciences & Engineering) 77:27 (2015) 127134
Table 4 Comparison of body symptoms among the male and female students (n = 500)
4.0 CONCLUSION
The survey is to evaluate student’s discomfort level
whilst sitting in Malaysia where the data was
collected, analyzed and summarized in order to
achieve the three objectives of this study. The results
indicated that the majority of male and female
students experienced a degree of discomfort in parts
of their body during their sitting process. The results also
indicated that the students’ main discomfort levels
were on the upper parts of their body (shoulder, upper
back, lower back and buttock) except the neck or
head . Majority of the students (male and female)
expressed no discomfort in their lower body part (arm
and hand, thigh, knee, calf leg below, ankle and
feet). The statistical test have indicated that there is a
total of four significant differences (p<0.05) (shoulder,
upper back, lower back and buttocks) among the
male and female students. These significant
differences indicate that individual factors such as
anthropometry and gender do have an effect on the
student sitting comfortability. Therefore, these study
findings can be useful for designers in the furniture
desk’ industry in order to enhance the ergonomic
relationship between the human (students) and
furniture. As a conclusion, the students in these
classrooms have discomfort levels whilst sitting in front
of their desk. Overall, the majority of the students feel
uncomfortable. Since modern societies value a better
quality of life, it is recommended that the user-friendly
design concept be used rather than the economic
theory be applied to educational furniture designs. It
is recommended that the design of a natural fibre
reinforced composite classroom desks for polytechnic
students for better comfortability and to also to
reduce cost manufacture.
Acknowledgment
This project was done as part of academic research
work in the polytechnic and no funding was received
from any of the government or private organization.
The authors thank the participants (students enrolled
in Polytechnic Kuching Sarawak, Malaysia) and
polytechnic staffs who helped to conduct this study
successfully.
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Lignocellulosic natural fibers like sisal and pineapple leaf fiber (PALF) can be incorporated in polymers based on biodegradable polyester amide matrix, BAK 1095 for achieving desired properties and texture in the resulting biocomposites. But high level of moisture absorption, poor wettability and insufficient adhesion between untreated fiber and the polymer matrix led to debonding with age. In order to improve the above qualities, various surface treatments of sisal fiber like mercerization, cyanoethylation, acetylation, bleaching and vinyl monomer (acrylonitrile) grafting are carried out which results in improved mechanical performance of sisal-BAK composites. Mechanical properties like tensile and flexural strength are optimum at a fiber loading of 50 wt%. Among all modifications, alkali treatment and acetylation result in improved properties of the composites. Alkali treated sisal composite shows about 20% increase in tensile strength and acetylated sisal composite shows about 14% increase in flexural strength compared to the control, i.e., untreated sisal based biocomposites. From the biodegradation study, we find that after 60 days of soil burial about 1% weight loss is observed for BAK whereas acetylated sisal-BAK composite shows maximum weight loss (22%). It also shows maximum decrease in flexural strength (47%) after 15 days of sisal burial. A comparative account of properties of PALF-BAK and sisal-BAK biocomposites is also given. Scanning electron microscopic studies were carried out for better understanding of fiber-matrix adhesion in biocomposites.
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This study was conducted to develop a prototype of an adjustable table and an adjustable chair for educational institutions, to evaluate its adoptability in accordance with international standards, and to validate the prototype chair by conducting subjective trials. The development process began with identifying the problems of existing adjustable tables and chairs currently available on the market. Minimizing the production cost to lower the market retail price; designing a stable and solid structure with minimum adjustment controls for easy adjustability; providing a flexible adjustment interval, adequate space for feet and knees; and reducing weight for easier mobility were the criteria for developing the prototype. The prototype's fundamental height adjusting mechanism, found on each leg, consists of a bar that rotates up and down through a cylinder. There are measurements on the bars so the height of all four legs can be evenly or independently adjusted forward or backward. In addition, the height of the backrest and the depth of the seat can be adjusted at the same time since the entire backrest can be moved forward or backward, upward or downward. The prototype chair was evaluated by comparing it with dimensions suggested by the ISO 5970 (Standards for tables and chairs for educational institutions) in terms of flexible range accommodations. Results of the comparison showed that the prototype developed in this study could be applied to these dimensions. Fitting trials were also done to test the user's first interaction with the chair. Results of these trials showed that the prototype came within range of subjective comfortable fitting dimensions.
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The study evaluated the potential mismatch between classroom furniture dimensions and anthropometric characteristics of 978 Iranian high school students (498 girls, 480 boys), aged 15-18 years. Nine anthropometric measurements (stature, sitting height, sitting shoulder height, popliteal height, hip breadth, elbow-seat height, buttock-popliteal length, buttock-knee length and thigh clearance) and five dimensions from the existing classroom furniture were measured and then compared together (using match criterion equations) to identify any potential mismatch between them. The results indicated a considerable mismatch between body dimensions of the students and the existing classroom furniture, with seat height (60.9%), seat width (54.7%) and desktop height (51.7%) being the furniture dimensions with a higher level of mismatch. The levels of mismatch varied between the high-school grade levels and between genders, indicating their special requirements and possible problems. The proposed dimensions of the classroom furniture more appropriate for the students were given. This additional information on students' anthropometry can be used by local furniture industries as a starting point for designing more appropriate furniture for school children, or used by schools to aid in furniture selection.
Article
This paper presents the results of an anthropometric survey carried out on a sample of male and female Bahraini school children aged 6–12 years (N = 1174), to throw some light on the anthropometric parameters of Bahraini students in order to provide school furniture designers and importers with relevant data. A set of 44 body dimensions covering most body parts were measured, from which six body dimensions relevant to school furniture design were considered. Results show a gradual increase from age 6 to age 12 in all body dimensions. When compared with children from other nationalities, Bahraini children were almost all of medium height and weight. This paper also shows how the results can be used in school furniture design.Relevance to industryThe 21st century has seen a lot of interest in children, especially school children as it is well known that many postural problems, such as back pain and repetitive strain injuries, start at an early age. Therefore, ergonomics design for children is as important as designing for adults. Anthropometric data are essential for this design.