Classroom furniture and anthropometric characteristics of Iranian high school students: Proposed dimensions based on anthropometric data

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.     

Book Review

Musculoskeletal symptoms are one of the top ten health problems among schoolchildren in Hong Kong. Whether or not these symptoms are related to school furniture has yet to be determined and published data on furniture size are lacking. The purpose of the study was to determine whether the design of furniture in schools is appropriate for children's anthropometry. A total of 214 volunteer subjects were recruited. This constituted 90% of the total number of primary 5 and 6 students in the studied school (i.e. those aged 10 and 13 years). The data collected included demographic information, data on perceived health and posture and body and furniture measurements. The girls' BMI was lower than that of the boys. The girls had longer lower limbs and wider hip breadth measurements in the standing position. This was similar in the sitting position. Almost none of the subjects had a chair with an appropriate seat height. Seat depth was found appropriate for large groups of students whether or not a large or small chair was used. Recommendations on the sizes of chairs and desks for boys and girls are discussed.     

Anthropometric evaluation for primary school furniture design

Musculoskeletal symptoms are one of the top ten health problems among schoolchildren in Hong Kong. Whether or not these symptoms are related to school furniture has yet to be determined and published data on furniture size are lacking. The purpose of the study was to determine whether the design of furniture in schools is appropriate for children's anthropometry. A total of 214 volunteer subjects were recruited. This constituted 90% of the total number of primary 5 and 6 students in the studied school (i.e. those aged 10 and 13 years). The data collected included demographic information, data on perceived health and posture and body and furniture measurements. The girls' BMI was lower than that of the boys. The girls had longer lower limbs and wider hip breadth measurements in the standing position. This was similar in the sitting position. Almost none of the subjects had a chair with an appropriate seat height. Seat depth was found appropriate for large groups of students whether or not a large or small chair was used. Recommendations on the sizes of chairs and desks for boys and girls are discussed.     

Mismatch between classroom furniture and anthropometric measures in Chilean schools

Children spend about five hours per day sitting down while doing their school work. Considering this as well as the potential inadequate use of school furniture, it is likely that some anatomical-functional changes and problems in the learning process may occur. The aim of this study was to compare furniture sizes within three different schools with the anthropometric characteristics of Chilean students in the Valparaíso region, in order to evaluate the potential mismatch between them. The sample consisted of 195 volunteer students (94 male, 101 female) of the 8th grade, ranging from 12.5 to 14.5 years of age from 3 different schools. Regarding the methodology, 6 anthropometric measures (Stature, Popliteal height, Buttock-popliteal length, Elbow height while sitting, Hip width, Thigh thickness and Subscapular height) were gathered, as well as 8 dimensions from the school furniture. For the evaluation of classroom furniture a match criterion equation was defined. After considering the existing classroom furniture dimensions in each match criterion equation, the anthropometric characteristics of the considered population were compared in order to determine the mismatch between them. Results indicated that seat height, which should be considered as the starting point for the design of classroom furniture, was appropriate for students' popliteal height in only 14% of the 2 out of the 3 schools, and 28% in the third. Seat to desk height was too high and mismatched 99% of the students in one school and 100% in the others. Therefore, it was possible to conclude that the classroom's furniture was inadequate in almost all the analyzed cases and subjects. It is possible that the high mismatch percentage found between furniture and students' anthropometry can be associated to the fact that the acquisition and selection of the furniture was made without any ergonomic concern or criteria.     

Are the desks and chairs at school appropriate?

The aim of the current study was to find out how the measures of chairs and desks match with the anthropometrics of schoolchildren and how schoolchildren sit during a lesson in their classroom. This paper reports the baseline measurements of an intervention study. Participants of this study were 6th and 8th grade (12 and 14 year old) schoolchildren from two comprehensive schools in Finland (N = 101, 57 girls and 44 boys). The main outcome measures were the differences between desk height and elbow-floor height, and chair height and popliteal height. Forty-three participants were randomized for sitting posture analysis by video recordings. The study showed that desks were on average 13 cm above elbow-floor height and chairs 2 cm below popliteal height. For 56% of time participants sat with their backs flexed >20 degrees and/or rotated >45 degrees . For 70% of time they sat with their necks flexed >20 degrees or rotated >45 degrees. The results indicate that there is a mismatch between school furniture and the anthropometrics of schoolchildren. Schoolchildren sit in disadvantaged postures for a substantial part of school lessons.     

Sitting and standing postures are corrected by adjustable furniture with lowered muscle tension in high-school students

This study compared the effect of 24 months of adjustable school desks and chairs usage (the intervention) and traditional non-adjustable usage (the control condition) on sitting and standing postures, muscle strength, classroom muscle tension, pain and learning in 15 (8 female and 7 male) high-school students and 15 anthropometrically and gender matched control students from neighbouring schools. It was assessed whether any responses took place after growth cessation. In comparison with controls, the intervention group of students' sitting postures standing kyphosis, scoliosis and lordosis became significantly better, both before and after growth cessation. Trunk muscle strength increased in the intervention students whose muscle tension during classes fell significantly in the trapezius and lumbar muscles, whereas in control students' lumbar tension increased. Headache and low-back pain correlated with neck-shoulder pain and trapezius muscle tension. Intervention students reported that they experienced benefits from the adjustable tables and chairs. They also received significantly better overall marks than the controls at the end of high school. It is concluded that the adjustable school desks and chairs promoted better sitting and standing postures, increased muscle strength, alleviated pain and appeared to be associated with better overall academic marks.     

Lack of conformity between Indian classroom furniture and student dimensions: proposed future seat/table dimensions

Children spend one-quarter of a day in school. Of this, 60-80% of time is spent in the classroom. Classroom features, such as workspace and personal space play an important role in children's growth and performance as this age marks the period of anatomical, physiological and psychological developments. Since the classroom is an influential part of a student's life the present study focused on classroom furniture in relation to students' workspace and personal space requirements and standards and was conducted in five schools at Mumbai, India. Dimensions of 104 items of furniture (chairs and desks) were measured as were 42 anthropometric dimensions of 225 students from grade six to grade nine (age: 10-14 years). Questionnaire responses of 292 students regarding the perceived adequacy of their classroom furniture were collected. Results indicated that the seat and desk heights (450 mm, 757 mm respectively) were higher than the comparable students' anthropometric dimensions and that of the recommendations of Bureau of Indian Standards (BIS) (340 + 3 mm, 380 + 3 mm seat-heights, 580 + 3 mm 640 + 3 mm desk-heights) as well as Time-Saver Standards (TSS) (381.0 mm seat-height and 660.4 mm desk-height). The depth of the seats and the desks (299 mm, 319 mm, respectively) were less than comparable students' anthropometric dimensions and the recommendations of BIS (IS 4837: 1990). Students reported discomfort in shoulder, wrist, knee and ankle regions. Based on the students' anthropometric data, proposed future designs with fixed table-heights and adjustable seat-heights along with footrests were identified.     

Equations for defining the mismatch between students and school furniture: A systematic review

The present study reviews the scientific literature that describes the criteria equations for defining the mismatch between students and school furniture. This mismatch may negatively affect students' performance and comfort. Seventeen studies met the criteria of this review and twenty-one equations to test six furniture dimensions were identified. There was substantial mismatch between the relative heights of chairs and tables. Some systematic errors have been found during the application of the different equations, such as the assumption that students are sitting on chairs with a proper seat height. Only one study considered the cumulative fit. Finally, some equations are based on contradictory criteria and need to develop and evaluate new equations for these cases.Relevance to industryUltimately, the present work is a contribution toward improving the evaluation of school furniture and could be used to design ergonomic-oriented classroom furniture.     

School furniture match to students' anthropometry in the Gaza Strip

This study aimed at comparing primary school students' anthropometry to the dimensions of school furniture and determining whether the furniture used matches the students' anthropometry. A sample of 600 male students, whose ages were between 6 and 11 years, from five primary schools in the Gaza Strip governorates participated in the study. Several students' body dimensions were measured. The dimensions measured included elbow–seat height, shoulder height, knee height, popliteal height and buttock–popliteal length. Measurements of the dimensions of the classroom furniture indicated that there was a considerable mismatch between the students' body dimensions and the classroom furniture. The mismatches in seat height, seat depth and desk height occurred for 99% of the students, while the mismatch for the back rest height was only 35%. Two design specifications were proposed in order to decrease the mismatch percentage based on the data obtained. The two proposed designs showed a considerable improvement in the match percentages as compared to the existing design.

Statement of Relevance: Having identified mismatches between the dimensions of the school furniture used in primary schools in the Gaza Strip, two new design specifications are proposed and shown to improve match with the students' anthropometric dimensions. The findings of the study are also an important addition to local knowledge on school children's anthropometry.     

Applying different equations to evaluate the level of mismatch between students and school furniture

The mismatch between students and school furniture is likely to result in a number of negative effects, such as uncomfortable body posture, pain, and ultimately, it may also affect the learning process. This study's main aim is to review the literature describing the criteria equations for defining the mismatch between students and school furniture, to apply these equations to a specific sample and, based on the results, to propose a methodology to evaluate school furniture suitability. The literature review comprises one publications database, which was used to identify the studies carried out in the field of the abovementioned mismatch. The sample used for testing the different equations was composed of 2261 volunteer subjects from 14 schools. Fifteen studies were found to meet the criteria of this review and 21 equations to test 6 furniture dimensions were identified. Regarding seat height, there are considerable differences between the two most frequently used equations. Although seat to desk clearance was evaluated by knee height, this condition seems to be based on the false assumption that students are sitting on a chair with a proper seat height. Finally, the proposed methodology for suitability evaluation of school furniture should allow for a more reliable analysis of school furniture.     

Seated buttock contours: a pilot study of Australian senior high-school students

Both posture and comfort of a chair are influenced by the contour and characteristics of the seat. Knowledge of seat contours of a student population could thus be useful in the design of school chairs. This study investigated seated buttock contours of senior high-school students in order to determine: (a) their general characteristics, (b) the effect of gender and sitting posture and (c) the relationship between the contours and selected anthropometric variables (stature and mass). A contour measurement device was developed and used to measure buttock contours in five sitting postures (typing, sitting up, sitting back, slumping and writing). Buttock contours were quantified by constructing anterior-posterior (AP) and lateral profiles from which six discrete profile dimension measurements were made. AP and lateral profiles were found to have a consistent shape across all participants. Five out of six profile dimensions were significantly different between genders, with just one significantly different between sitting postures (typing and sitting back). Correlations between anthropometric measures and profile dimensions were relatively low (r < 0.34) with no clear patterns evident. Overall results of this study suggest that buttock contours are influenced by gender to a greater extent than sitting posture.     

The use of adjustable furniture: Evaluation of an instruction programme for office workers

A programme was designed in which instruction was given in the optimal adjustment of seat and desk height based on individually measured body dimensions. The programme was evaluated by means of measurement of seat and desk height before and after instruction to an experimental group in comparison with a control group to which no instruction was given. In the experimental group, prior to instruction, the mean deviation from the ideal sitting posture measured 71 mm for seat height and 70 mm for desk height. After instruction this deviation decreased by 11 mm for seat height and 18 mm for desk height. Although this is a statistically significant change, it is of limited practical importance since for seat height only 7% (3 of 41) and for desk height 13% (5 of 40) adjusted their furniture effectively as they were advised. The reasons for this meagre result are assumed to be the arbitrary concept of an ideal sitting posture, difficulties in obtaining extra adjustments in the form of footrests and desk elevation, the social acceptability of the advice given, and practical impediments that can occur while adopting an ideal sitting posture.     

The effect of secular trends in the classroom furniture mismatch: support for continuous update of school furniture standards

In order to create safer schools, the Chilean authorities published a Standard regarding school furniture dimensions. The aims of this study are twofold: to verify the existence of positive secular trend within the Chilean student population and to evaluate the potential mismatch between the anthropometric characteristics and the school furniture dimensions defined by the mentioned standard. The sample consists of 3078 subjects. Eight anthropometric measures were gathered, together with six furniture dimensions from the mentioned standard. There is an average increase for some dimensions within the Chilean student population over the past two decades. Accordingly, almost 18% of the students will find the seat height to be too high. Seat depth will be considered as being too shallow for 42.8% of the students. It can be concluded that the Chilean student population has increased in stature, which supports the need to revise and update the data from the mentioned Standard.     

Anthropometrics for the design of Bahraini school furniture

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 industry

The 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.     

Neural network and multiple linear regression to predict school children dimensions for ergonomic school furniture design

The current study investigates the possibility of obtaining the anthropometric dimensions, critical to school furniture design, without measuring all of them. The study first selects some anthropometric dimensions that are easy to measure. Two methods are then used to check if these easy-to-measure dimensions can predict the dimensions critical to the furniture design. These methods are multiple linear regression and neural networks. Each dimension that is deemed necessary to ergonomically design school furniture is expressed as a function of some other measured anthropometric dimensions. Results show that out of the five dimensions needed for chair design, four can be related to other dimensions that can be measured while children are standing. Therefore, the method suggested here would definitely save time and effort and avoid the difficulty of dealing with students while measuring these dimensions. In general, it was found that neural networks perform better than multiple linear regression in the current study.     

Mismatch between classroom furniture and anthropometric measures of university students

The appropriate design of tools, equipment and accessories for human body sizes, while meeting the social, cultural, economic and psychological needs of people, provides maximum benefit. This is crucial for students who spend most of their time using school furniture. The aim of the study is to investigate the mismatch between school furniture dimensions and students’ anthropometric measures. Nine anthropometric measures were taken of 225 students (68 female and 157 male) from nine departments of an engineering faculty using a specially designed measurement tool. The mismatch percentages between the existing classroom furniture dimensions and the anthropometric measures were determined using some well-known criterion equations. The results indicated a considerable mismatch: 44.45% for seat height, 100% for seat depth, and 21.28% for desk height. Two types of proposed classroom furniture achieved much higher percentage matches. The match percentages were above 70% for four dimensions for type A and above 95%, except for seat height and width of backrest, for all of the dimensions for both types.Relevance to industryThis study helps in establishing and motivating necessary further studies in classroom ergonomics in university settings.     

School furniture and the user population: an anthropometric perspective

The purpose of this study was to determine the relationship between reported spinal symptoms in an adolescent student population, and the match between their individual anthropometric dimensions and their school furniture. The hypothesis was that students who were too large or too small for their school furniture, i.e. with anthropometric measurements furthest from the group whose anthropometry was the 'best fit' with the furniture, would have a higher frequency of reported symptoms. From data collected from 1269 schoolchildren, reported spinal symptoms and anthropometric measures were examined. Stature measures were divided into quartiles. A standard government issue school chair and desk was measured and the anthropometric quartile of the population having the 'best fit' with the furniture was identified using standard ergonomics recommendations. Odds ratios were calculated for spinal symptoms reported within each quartile group. The first quartile group (the smallest students) was identified as having the 'best fit' with the school furniture. An overall higher odds of reporting low back pain was noted in students with anthropometric dimensions in the fourth quartile (the tallest students). While it is acknowledged that there is a multifactorial nature of causality of adolescent spinal symptoms, it is contended that the degree of mis-match between child anthropometry and school furniture set-up should be further examined as a strong and plausible associate of adolescent low back pain.     

School furniture and the user population: an anthropometric perspective

The purpose of this study was to determine the relationship between reported spinal symptoms in an adolescent student population, and the match between their individual anthropometric dimensions and their school furniture. The hypothesis was that students who were too large or too small for their school furniture, i.e. with anthropometric measurements furthest from the group whose anthropometry was the ‘best fit’ with the furniture, would have a higher frequency of reported symptoms. From data collected from 1269 schoolchildren, reported spinal symptoms and anthropometric measures were examined. Stature measures were divided into quartiles. A standard government issue school chair and desk was measured and the anthropometric quartile of the population having the ‘best fit’ with the furniture was identified using standard ergonomics recommendations. Odds ratios were calculated for spinal symptoms reported within each quartile group. The first quartile group (the smallest students) was identified as having the ‘best fit’ with the school furniture. An overall higher odds of reporting low back pain was noted in students with anthropometric dimensions in the fourth quartile (the tallest students). While it is acknowledged that there is a multifactorial nature of causality of adolescent spinal symptoms, it is contended that the degree of mis-match between child anthropometry and school furniture set-up should be further examined as a strong and plausible associate of adolescent low back pain.     

Effects of seat slope and hip flexion on spinal angles in sitting

Lumbar and thoracic spinal angles of 25 male and 25 female subjects were measured in four sitting postures, with standing angles used as reference. Subjects sat with either 90 deg or 65 deg of hip flexion on either flat or forward-sloping seats. Lumbar kyphosis was greatest when the flat seat/90-deg posture was adopted and least when the sloping seat/65-deg posture was adopted. The opposite was observed for the thoracic angles, and intermediate results were observed for the other two sitting postures. No statistically significant interactions were observed among seat slope, hip flexion, and subject sex. The findings are discussed with reference to the anatomy of sitting and factors influencing pelvic tilt and the implications for the ergonomic design of chairs.