In nothern Spain two pairs of large ventilation turbines fell down for unknown reasons. It happened in the Candás tunnel on the AS-118 highway between the towns of Gijón and Luanco. Quite a scare for motorists but luckily...

  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....