Iranian Journal of Ergonomics

According to the observations made by most of the students when using educational furniture they are not in good condition. Standing while drawing, static posture, and bending forward for a long time in a sitting position make students often put a lot of physical pressure on their muscles, ligaments, and especially on the intervertebral discs [2]. Thus, undoubtedly, attention to spinal abnormalities and identifying the factors that cause them and providing motor corrective strategies will result in correction of physical condition in addition to providing health and reducing possible injuries [7, 8]. The purpose of this study was to investigate the degree of student satisfaction with the design and construction of an ergonomic drawing board and chair corresponding to the physical dimensions of the students in the kindergartens. Undoubtedly, attention to spinal abnormalities and identifying the factors that cause them and providing corrective motor remedies, in addition to providing wellness and reducing possible injuries, will result in proper physical condition [3].

 

This cross-sectional study was conducted to evaluate the status of drawing tables and chairs available at conservatories. A Likert-type questionnaire consisting of 40 items in five ranges of very good, good, fairly good, bad and very bad, and a statistical population of 600 students were selected through multistage cluster random sampling from all areas of education. The selected city of Mashhad was broadcast. For the study, a sample of 160 male students aged 15 to 18 years from four conservatory schools in Mashhad and 40 first year students from a college affiliated with technical and vocational universities in the first and second semesters were selected. Factor analysis was used to identify the factors that are important for the design of the conservatory table chairs, based on the factors that were identified as the most effective factors, including weight, height, thigh thickness, knee length, poplar space, knee height, poplar height, elbow to seat height, hip length, shoulder height and buttock width. Descriptive analysis was used to analyze the data using SPSS (SPSS Inc., Chicago, Ill., USA). Accordingly, in the first part, the data analysis of the first questionnaire was analyzed and the students' satisfaction with the formal desks available at the kindergartens was determined. In the second part, data from anthropometric data of students were calculated by means of the standard, frequency, mean, standard deviation, median, fashion, variance, range. In this study linear distance measurements were used in static anthropometric method [15]. For evaluation of anthropometric characteristics, nine anthropometric dimensions including weight, height, shoulder height, sitting height, popliteal width, elbow height, sitting elbow height, hip length and thigh thickness were measured for each individual. To design and manufacture ergonomic drawing table and chair according to body dimensions, students' anthropometric measurements were performed in two sitting and standing positions.

Table 1. How to determine dimensions of drawing desk and chair based on anthropometry based on BS5873 model

Figure 1. Student position sitting on anthropometric chair

The results of the study of the drawing table and chair in the conservatory showed that the overall condition of the desk and the drawing chair in the conservatory were very bad (54.54%), bad (31.98%) and very good (3.29%). The results are expressed in Figures 2-4. Also the anthropometric parameters (identified factors) measured by the students used in the ergonomic design of the mapping table and benchmark in terms of statistical indices such as mean, standard deviation, median, mode, variance, range are presented in Table 2. The study of anthropometric data showed that, except for the height and thigh parameter, there was no significant difference between the different educational levels.

Figure 2. General status of the official tables and chairs in the conservatory




Figure 3. Satisfaction with the status of the conservatory drawing table




Figure 4. Satisfaction with the status of the drawing board of the conservatory

Table 2. Measured Anthropometric Parameters of Mashhad High School Students

After statistical analysis of data obtained from anthropometry of nursery students and using percentiles according to BS 5873, the main dimensions of table and chair according to Table 3 were obtained and used in its ergonomic design.

Table 3. Main dimensions of desk and chair

Taking into account the dimensions obtained in Table 2, the drawings of the desk and chair drawings, including: Perspective and Explosive Perspective, were drawn and constructed using AutoCAD and Solid Works software (Figure 5).

Figure 5. A. Perspective and Dimensions of Drawing desk B. Explosive Drawing Perspective

Table 2 was also used to design the drawing chair, with its executive maps including Perspective, Explosive Perspective in Figure 6.

Figure 6. A. Perspective and Dimensions of Drawing Chair Dimensions B: Explosive Drawing Chair Perspective

To determine the proportions of furniture dimensions with ergonomic and anthropometric criteria, we can use the relationships established by the researchers after adjusting the measured characteristics of the students and placing them in relationships, the proportion of desk and chair components to the students' physical dimensions, as shown in Table 4 [14].

Table 4. Proportional dimensions of drawing desk and chair designed for students' physical dimensions

Investigation of the correlation between the mean scores obtained from the two methods used in this study for all workers showed a significant but moderate correlation between the scores obtained from the two methods. Correlation between prevalence of musculoskeletal disorders obtained from Nordic questionnaire and final scores of QEC and WERA methods also showed that results of QEC method are closer and more consistent with results of Nordic questionnaire.

 

In this study, there was a lot of dissatisfaction among students due to the lack of matching these educational materials with their physical dimensions which has caused physical, mental and psychological damage and poor quality of education. At the end of the study, through ergonomic design, matters of satisfaction, sustainability and reduced production costs and also the reasons for students' dissatisfaction with the drawing desk and chairs is presented.

 

The authors would like to thank and thank all the dear ones who assisted the authors in this study.

 

The authors declared no conflict of interest.