1 Subject content and scope of application 1.1 Subject content This standard specifies the distance to watch teaching TV, horizontal oblique angle of view and elevation angle, classroom lighting coefficient, artificial illumination average illumination and illumination uniformity and other relevant requirements 1.2 applicable scope of this standard It is applicable to classrooms where TV is the main teaching method in all kinds of schools in China. Other types of classrooms equipped with televisions should also be used. 2 Seat arrangement range 2.1 The horizontal distance from the front edge of the chair to the vertical plane of the TV screen is calculated as a multiple of the size of the TV tube. The minimum is 4 to 5 times and the maximum is 10 to 11 times. 2.2 The horizontal oblique angle of the student watching TV shall not exceed 45°. 2.3 The elevation angle of students watching TV must not exceed 30°. 3 Illumination 3.1 The minimum natural lighting factor on the desktop of the TV classroom should not be less than 1.5%. 3.2 When using television to teach, the average illumination of classroom artificial lighting should be 60±61x, and the illumination uniformity should not be lower than 0.7. 3.3 TV classroom lighting should use fluorescent light as the light source, no bare light, the light is not less than 1.7 ~ 2.0m from the desk table, the lamp should be arranged so that its long axis is perpendicular to the blackboard surface. 3.4 Lighting Design When calculating illuminance, the illuminance compensation factor is taken as 1.3. 3.5 Considering that TV classrooms are used for other purposes, indoors can be equipped with lights and blackboard lights according to the requirements of ordinary classrooms, and the control switches of the lights should be grouped according to different functions. 3.6 Illuminance measurement An illuminometer with cosine correction and color correction applied and must be calibrated. The measurement lighting and illumination are carried out according to GB 5699-85 "Lighting Measurement Method" and GB 5700-85 "Indoor Lighting Measurement Method". 3.7 TV classrooms should have measures to prevent the light source from generating glare on the screen. 3.8 TV classrooms must have dimming facilities and enhanced ventilation. 4 Noun explanation 4.1 The horizontal oblique viewing angle of the viewing television The angle of the viewer in the horizontal direction from the central axis of the television screen (such as the angle α in Fig. 1). 4.2 Watch the angle between the viewer's horizontal line of sight and the center of the TV screen (see the angle β in Figure 2). 4.3 Illumination Uniformity The ratio of the minimum illumination to the average illumination on the desktop of the classroom. 4.4 Turning on the dark facilities to block the exposure of natural light into the classroom during TV instruction. Such as electric or manual blackout curtains (requires curtain boxes) or shaded ventilation shutters. Appendix A Facilities for Preventing Reflective Glare on TVs (Reference) There are many measures to prevent the light source from generating glare on the TV screen. One of them is to add a visor to the TV case (as shown below). The plate is made of an opaque material, the length of which projects forwardly is inversely proportional to the height of the lamp from the television. Additional notes: This standard was proposed by the National Health Standards Technical Committee School Health Standards Subcommittee. This standard was drafted by Huaxi Medical University. This standard is interpreted by the Children's and Adolescent Health Research Institute of Beijing Medical University, which is entrusted by the Ministry of Health.
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