Smart Safety Design for Evacuation Signs in Large Space Buildings Based on Height Setting and Visual Range of Evacuation Signs

In case of emergency, evacuation signs play an important role in guiding people to evacuate safety exits in large space buildings. Large space buildings are characterized by high ceilings and large areas. In the existing legislation and standards, the height setting of evacuation signs is fixed, but the influence of height changes on the visibility of evacuation signs is very important. This study fully considers the relationship between the height setting change of evacuation signs and the visual range and puts forward a smart safety design strategy for evacuation signs. The smart safety design consists of two parts, one is the mathematical relationship between the height change of evacuation signs and the visual range of personnel, and the other is the integration of the application process of smart devices. Firstly, the visual range of two different sizes of evacuation signs placed at the height of 1.7 to 6 m was measured experimentally in China. The results showed that: (1) with an increase in the height of the evacuation signs, their viewing distance gradually decreased and the visual range was reduced; (2) the mathematical model of the change between the height and the visual range of evacuation signs was established; (3) the height of evacuation signs between 3 to 5 m agreed more with the visual habits of the people. Then, on this basis, the smart safety design method can use related mathematical models to set the evacuation signs at the optimal height based on the actual distance between people and evacuation signs, ensuring that people can see the signs the first time, thus providing evacuation guidance for evacuees and improving the safety of large space buildings.