Abstract
The rise in the use of underground infrastructure, such as road tunnels and subterranean workplaces, addresses urban space limitations by minimizing urban sprawl and preserving green areas. This shift enhances quality of life in urban settings and provides security against threats, including extreme weather and geopolitical conflicts. However, underground facilities present challenges, primarily regarding safety, public trust, and orientation. Psychological barriers, such as concerns for safety and claustrophobia, must be mitigated to ensure user comfort. Emergency exit systems are essential in providing the necessary sense of safety and control. Ensuring effective wayfinding in these environments is crucial, given the absence of natural landmarks, which necessitates a combination of visual and acoustic guidance systems. During evacuations, rapidly locating the nearest exit is critical. Sensory guidance plays an essential role in assisting individuals towards exits swiftly, especially in compromised visibility conditions. While lighting and signage are frequently employed, they may be ineffective in smoke- filled environments. Recent research and development of emergency exit systems are discussed considering universal design principles and the role of directional sound signals.