1、发生火灾时，烟气先垂直上升，到达顶棚后再水平扩散，聚满储烟仓后再扩散至其他防烟分区。
1. In case of fire, the smoke rises vertically first, then diffuses horizontally after reaching the ceiling, and then diffuses to other smoke prevention zones after gathering in the smoke storage bin.
2、烟气上升过程中，到达一定高度后，温度下降，烟气下沉。
2. In the process of flue gas rising, after reaching a certain height, the temperature decreases and the flue gas sinks.
3、地下疏散和通风比地上困难，因此地下防排烟要比地上严格。
3. Underground evacuation and ventilation are more difficult than above ground, so underground smoke control is more strict than above ground.
4、人在烟气中低头掩鼻的最大行走距离为20m～30m。
4. The maximum walking distance of a person who lowers his head and covers his nose in smoke is 20m ~ 30m.
5、机械排烟是让着火区域局部形成相对负压。
5. Mechanical smoke exhaust is to form relative negative pressure locally in the fire area.
6、机械排烟是让烟气有序运行并排出建筑物。
6. Mechanical smoke exhaust is to make the smoke run orderly and discharge out of the building.
7、中庭发生火灾时会产生烟囱效应。
7. A fire in the atrium will produce a chimney effect.