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In order to improve the lighting and lighting conditions in the classroom, improve the teaching effect, protect the students' vision, and enable children and adolescents to grow up healthily, the standard is formulated. This standard is applicable to ordinary primary and secondary schools, secondary normal schools and preschool teachers' schools for the construction, reconstruction and expansion of cities, counties and towns.
★ Definition of terms
(1) Daylighting coefficient: The daylighting coefficient at a certain point in the room is the ratio of the illuminance at that point to the illuminance of the outdoor diffused light at the same time, expressed in %.
(2) Slope to ground ratio: the ratio of the light transmission area of ​​the glass to the indoor floor area.
(3) Direct glare: glare caused by the illuminant existing in the direction of the observation object or close to this aspect.
(4) Reflection coefficient: The ratio of the optical flow reflected on an object to the optical flow incident on the object is called the reflection coefficient and is denoted by p.
(5) Illuminance uniformity: the ratio of the minimum illuminance to the average illuminance on a given work surface.
(6) Illumination compensation coefficient: The ratio of the average illuminance produced by the new illuminator on the work surface to the average illuminance produced by the same illuminator under the same conditions after a certain period of use.
★ Lighting in the classroom
(1) The orientation of the school classroom should be determined according to the geographical and climatic conditions of each region. It should not be oriented east-west. It is advisable to use both sides of the north-south direction. When the classroom uses single-sided lighting, the light should be incident from the left side of the student's seat. When the classroom is located in the south of the corridor, the north window should be the main lighting surface.
(2) The minimum value of the daylighting coefficient on the desk of the classroom should not be less than 1.5%, and the classroom glass area ratio should not be lower than 1:6. The minimum value of the daylighting coefficient on the desktop of a classroom in a foggy area (such as Chongqing) should not be less than 2%.
(3) In order to prevent direct glare of the window, the classroom should be provided with curtains to prevent direct sunlight from entering the classroom. In order to prevent the glare of the blackboard, the surface of the blackboard should be made of wear-resistant and matt material.
(4) In order to improve the lighting effect of the classroom, the indoor surfaces should be decorated with high brightness and low chroma. The reflection coefficient of each surface of the room should be selected according to the provisions of the attached table.
(5) The lighting measurement method shall be implemented in accordance with GB5699-85 "Lighting Measurement Method".
★ classroom lighting
(1) Artificial lighting should be installed in the classroom.
(2) The average illuminance value on the desk of the classroom should not be less than 150 lx, and the uniformity of illumination should not be less than 0.7.
Reflection coefficient value of each surface of the attached table surface name reverse coefficient (%)
Ceiling 70-80
Front wall 50-60
Ground 20-30
Side wall, back wall 70-80
Lesson desktop 35-50
Blackboard 15-20
(3) The classroom blackboard shall be provided with a local illumination lamp whose average vertical illumination shall not be less than 200 lx and the illumination uniformity shall not be less than 0.7.
(4) Fluorescent lamps should be used for classroom lighting sources.
(5) In order to reduce the direct glare caused by the illumination source, the classroom should not use bare light illumination. The minimum suspension height of the luminaire from the desk table should not be less than 1.7m. The arrangement of the tubes should be such that their long axes are perpendicular to the blackboard surface. For the step classroom, the front row of lights should not cause direct glare to the students in the back row.
(6) Illumination design When calculating the illuminance, the illuminance compensation coefficient is taken as 1.3.
(7) The indoor lighting measurement method is implemented according to GB5700-85 "Indoor Lighting Measurement Method".
★ The standard was drafted by Zhang Shaogang, Zhao Rong and Pang Yunfan of the Institute of Building Physics of China Academy of Building Research and the Department of Health of Shanxi Medical College. It was implemented on March 1, 1988 with the approval of the Ministry of Health of the People's Republic of China.
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