Indonesian National Standard Based Comparison of Classroom and Library Illuminance in A Junior High School

Abstract

This study compares illuminance performance in a junior high school classroom and library using measured afternoon data and the illuminance criteria of Indonesian National Standard (SNI) 6197:2020. The classroom (9 m × 7 m) was evaluated at 80 points, whereas the library (11 m × 7 m) was evaluated at 82 valid points because of its irregular corner. Measurements were recorded from 13:00 to 15:00 at 20 min intervals. Raw data from the uploaded workbook were recalculated from point readings; for the library sheet, the recorded values were converted from a ×10 scale to lux before analysis. The analysis used average illuminance, minimum and maximum values, uniformity (Emin/Eavg), temporal comparison, and compliance with the 350 lux standard for classrooms and library reading rooms. The results show a very large performance gap between the two spaces. The classroom achieved an average of 27.48 lux, or 7.85% of the SNI target, and none of the observed points reached 350 lux. By contrast, the library achieved an average of 652.93 lux, exceeding the standard by 86.55%; however, its distribution was highly uneven, with strong peaks near daylight-dominant zones and several underlit edge areas. These findings indicate that the classroom requires immediate lighting improvement, while the library requires daylight control and redistribution rather than additional light output. The study provides practical evidence for evaluating school lighting conditions based on field measurements and SNI benchmarks.