Objective: To understand the trends of classroom lighting and illumination of primary and secondary schools in Beijing from 2016 to 2023, so as to provide a scientific basis for targeted improvement measures. Methods: A sampling survey was conducted on the lighting and illumination indicators of 8 390 classrooms in primary and secondary schools in Beijing from 2016 to 2023. The survey included classroom daylight factor, window to floor area ratio, average illuminance and illuminance uniformity on the desks, average illuminance and illuminance uniformity on blackboards, as well as classroom lighting and blackboard illumination sources. Intergroup comparisons were performed using the Kruskal-Wallis H test and the Chi square test, and Spearman correlation analysis was used to examine the trend of classroom lighting and illumination changes. Results: Except the window to floor area ratio, the measured values and compliance rates of all lighting and illumination indicators showed an overall upward trend from 2016 to 2023 (daylight factor r = 0.27, χ 2 trend =206.80, average illuminance on the desk surface r =0.30, χ 2 trend =87.97, illuminance uniformity on the desk surface r =0.14, χ 2 trend =73.59, average illuminance on the blackboard r =0.33, χ 2 trend =477.43, illuminance uniformity on the blackboard r = 0.09, χ 2 trend =50.76) (all P ＜0.01). The lighting and illumination indicators of classrooms (included classroom daylight factor, average illuminance and illuminance uniformity on the desks, average illuminance and illuminance uniformity on blackboards) in urban schools, primary schools, and secondary schools from 2016 to 2023 showed an upward trend (urban r =0.23-0.40, χ 2 trend =88.66-392.18; primary school r =0.12-0.36, χ 2 trend =39.50-281.44; secondary schools r =0.06-0.31, χ 2 trend =11.79-213.73) (all P ＜ 0.01 ). The illuminance uniformity on the blackboard in suburban schools showed a downward trend ( r = -0.09, χ 2 trend =31.53, both P ＜0.01). The illuminance uniformity on the desk surface in suburban schools showed no significant change ( r =0.03, χ 2 trend =1.23, both P ＞0.05). The other indicators showed an upward trend (daylight factor r =0.28, χ 2 trend =40.69, average illuminance on the desk surface r =0.24, χ 2 trend =16.35, average illuminance on the blackboard r =0.25, χ 2 trend =118.05, all P ＜0.01). The trends of classroom and blackboard illumination sources were that fluorescent lamps decreased year by year and LED lamps increased by year (classroom illumination sources χ 2 trend =1 059.82, blackboard illumination sources χ 2 trend =1 070.25, both P ＜0.01). Conclusions The classroom lighting and illumination in primary and secondary schools in Beijing has shown an overall improving trend from 2016 to 2023. However, problems remain, such as limited improvement of illuminance uniformity indicators, late start and poor effect of reconstruction in suburban schools. Further improvements are still needed.

Objective: To understand the current situation of teaching and living environment in primary and secondary schools in Beijing and to provide basis for further intervention. Methods: According to the national plan, an annual average of 92 schools in 16 districts of Beijing were investigated from 2017 to 2020, including school drinking water, canteen, toilet, dormitory management and equipment allocation. Classroom environment of some schools were tested,including the per capita area of classrooms, the agreement rate of desks and chairs distribution, blackboard reflectance, the average illumination and uniformity of desks, the average illumination and uniformity of blackboards, and noise. Results: From 2017 to 2020,most of schools provided water purifiers and direct drinking water, accounting for 85.1% of all investigated schools. The proportion of students canteens in urban schools was increasing,accounting for 90.5% of all schools in 2020. And there was little change in suburban schools,reaching 85.1% in 2020. The proportion of school toilets equipped with soap increased significantly, 92.0% of school toilets were equipped with soap in 2020. The proportion of student dormitories with a per capita area of less than 3 m 2 decreased by year, and all reached the standard in 2020. The qualified rates of various classroom testing indicators, including per capita area in classroom, desk illumination uniformity, and noises, were higher than 80%, while the qualified rates of the blackboard illumination uniformity, desk allotment were lower than 80%. Conclusion The teaching and living environment in Beijing has improved in recent years, but there are still some problems need to be solved.

Objective: To understand the sanitation status of teaching environment of schools in Beijing, and to provide basis for school environmental improvement through monitoring it. Methods: In 2019, 661 primary and secondary schools were selected according to the coverage rate of 50% of all schools. Two classrooms were randomly selected from each school for testing, 1 322 classrooms were monitored. The testing contents included per capita area of the classroom, rate of correct desks-chairs adjusting for school height, blackboard size, reflection ratio of blackboard,illumination, carbon dioxide and noise. Results: The qualified rate of noise(92.3%), per capita area(86.5%), blackboard size (85.6%) and illumination uniformity of table top (83.4%) were higher than 80%, while the qualified rate of other indexes were lower than 80%. In 2019, the qualified rate of blackboard size, blackboard average illuminance and blackboard illuminance uniformity were higher than 2018 year(85.6%, 52.7%, 36.2%; 81.9%, 42.7%, 31.7%)(χ2=10.97, 7.80, 5.90, P<0.05), while the noise (92.3%) was lower than 2018 year(98.3%)(χ2=70.82, P<0.05). Both classroom and blackboard, the average illuminance and evenness of the desk and blackboard installed with LED light were higher than those installed with fluorescent lights. Conclusion Teaching environment monitoring in Beijing is not optimistic. It is necessary to strengthen the promotion and evaluation of standards,and the classroom environment needs to be further improved.