Ergonomics in schools: Situation in Sri Lankan early adolescents

Introduction
School health promotion should be holistic and need-based. The focus of school environment absorbing international attention currently is ergonomics. Incompatible ergonomics impart negative impacts on schoolchildren.

 Objectives :

To describe the distribution of selected ergonomic factors related to school-going early adolescents.

 Method :
A descriptive cross-sectional study was conducted with a sample of 1607 schoolchildren of 11–13 years selected using stratified multistage cluster sampling in a district of Sri-Lanka. Selected anthropometric and measurements related to schoolbag, chair, desk and location of seating were taken and compared for ergonomic compatibility.

 Results:

There were 52% male and 48% female students from urban (31.7%) and rural (68.3%) schools. They carried books in backpacks (79.6%), shoulder bags (17.9%) and suitcases (2.3%). Mean weight of schoolbag was 3.72Kg. Mean schoolbag weight/body weight was 11.04% (SD=3.88). A bag weighing >10% of bodyweight was carried by 57.9%. Children were seated with a mean angle of 30.71 degrees (SD=19.67) and 398.04cm (SD=132.09) mean distance to blackboard. 23.3% had to turn >45 degrees to see the blackboard.

A government-issued standard chair with backrest without hand-rests was used by 95.6%. Regular use of backrest was reported by 12%. For 78.3% an individual desk was provided. Desk surface was horizontal in 84.9%. A foot-rest was present in 82% desks. Sitting area length of chairs did not match with buttock-popliteal length of child in 87.3%, A mismatch in seat height and popliteal height was observed in 79.8% while legroom height of desk did not comply with popliteal height in 76.3%.

 Conclusions :

A majority of children carried a healthy bag model, backpack, which causes minimal physiological distress. Many children carried a schoolbag weighing above the international cut-off of 10%. More than 80% of students were not provided with compatible chair/desk combination. Ergonomics related to school-going adolescents are unsatisfactory.