'Noise Barrier Tunnels' Increasing Fire Damage on Roads

Made of Flammable Material, Vulnerable to Fire
Similar Incident on Yongin Overpass in 2020

On the afternoon of the 29th, firefighters are extinguishing remaining flames in the soundproof tunnel section of the 2nd Gyeongin Expressway near Gwacheon Knowledge Information Town in Gwacheon-si, Gyeonggi-do, where a fire occurred. [Image source=Yonhap News]

[Asia Economy Reporter Kang Juhee] On the 29th, an accident occurred near the Bukuiwang IC section of the 2nd Gyeongin Expressway in Galhyeon-dong, Gwacheon-si, Gyeonggi-do, resulting in the deaths of five people. The fire started from a collision between a bus and a truck traveling on the expressway, but it is estimated that the fire quickly spread into the soundproof tunnel, increasing the casualties.

Soundproof tunnels are constructed to reduce traffic noise. The problem lies in the materials used in the soundproof tunnel, which are plastic and vulnerable to fire. According to the standard specifications established by the Ministry of Land, Infrastructure and Transport, the transparent soundproof panels in soundproof tunnels use plastics such as polymethyl methacrylate (PMMA) and polycarbonate (PC). These two materials are resistant to external impact and highly durable, but they are combustible materials vulnerable to fire.

Footage taken during the recent soundproof tunnel fire shows the interior of the tunnel engulfed in flames with large amounts of black smoke billowing out. The ceiling, which turned red from the fire, is seen melting and dripping.

In August 2020, a fire broke out inside the soundproof tunnel under the overpass at Shindae Lake Intersection in Sanghyeon-dong, Suji-gu, Yongin-si, Gyeonggi-do, originating from a BMW vehicle traveling inside the tunnel. Although there were no casualties, the fire that started from the vehicle spread to the soundproof tunnel, burning about 50 meters inside the tunnel.

Experts believe that the damage was exacerbated in this recent soundproof tunnel fire because the fire spread through the combustible soundproof tunnel panels. Professor Gong Haseong of the Department of Fire Protection and Disaster Prevention at Woosuk University explained, "Plastic materials such as PMMA and PC are lightweight and easy to install, so they are widely used at construction sites. However, in case of fire, they spread flames faster than wood and produce a large amount of toxic gases, increasing the risk of casualties."

He added, "Countries like Germany and Japan use non-combustible materials for soundproof panels," and said, "It is necessary to reorganize fire safety standards related to soundproof tunnels domestically as well."