Tunnel fans, also known as tunnel jet fans, are essential ventilation devices widely utilized in tunnels of various types, including highways, railways, subways, and even water conservancy projects. These fans effectively manage air circulation within tunnels, ensuring a safe and healthy environment for both workers and users. By removing harmful gases, pollutants, and excess heat, they maintain optimal air quality and temperature, crucial in hot and humid climates. Tunnel fans come in various forms, including unidirectional and bidirectional models, tailored to specific ventilation needs and tunnel dimensions. Their strategic placement and operation contribute significantly to enhancing visibility and reducing the risk of accidents caused by fog or smoke accumulation.