This study investigates the potential application of small-diameter jet fans (φ 450) as a new tunnel ventilation system．Traditionally，tunnel ventilation has relied on large-diameter jet fans (φ1000 or φ1250)，which are typically suspended above traffic lanes．However，following the Sasago Tunnel ceiling panel collapse，ensuring the safety of suspended equipment has become increasingly important，and various safety measures have since been implemented．In response to these concerns，this study aims to further enhance safety by conducting full-scale tunnel ventilation tests to evaluate the performance of small-diameter jet fans (φ 450)．The results confirmed that these fans provide a certain level of ventilation performance，suggesting their potential applicability in future tunnel ventilation systems．
Ohta et al. (Wed,) studied this question.