Turkish companies produce good ventilation systems such as Teknima and EMAK.

You can check EMAK tunnel ventilation systems at internet address https://emak.com.tr

EMAK is headquartered in İstanbul and has a factory in closeby Yalova. EMAK tunnel ventilation systems have been used in 7 bid metro systems and 220 tunnels worldwide in over 50 countries. EMAK is a major OEM supplier to some major European tunnel ventilation companies.

https://emak.com.tr/tunnel-ventilation-systems/