<Anchor>

In this incident, the toxic gas in the tunnel immediately following the fire caused more casualties because of neither easy evolution nor rescue. There was no sprinkler or smoke removal facility in the tunnel, but it was confirmed that it was not installed because the tunnel length was shorter than the standard.

I am a reporter.

<Reporter>

At the time of the accident, the tunnel was filled with nitrates from the tank lorry and toxic gases from the fire.

380 firefighters were put in, but this toxic gas struggled with early evolution and rescue.

Eventually, they had to deal with toxic gas and catch the fire only four hours after the accident.

Had there been a sprinkler or smoke control in the tunnel, it would have saved evolution and rescue time, but there was no such thing in the accident tunnel.

These disaster prevention facilities were not installed in the 710m Sasan Tunnel, which had an accident according to the Ministry of Land, which allowed the tunnel to be installed more than 1km long.

Tunnels that are less than 1 km long are equipped with smoke control, depending on the traffic volume.

There are 405 short tunnels, less than 1 km in size, managed by road construction, of which only 10% have 42 ventilation facilities.

As a result, the Ulsan-Pohang Expressway Bumseo 2 Tunnel, which was injured by six people in a truck fire in June 2018, also has a 610m length and no smoke control.

Experts say enclosed tunnels are easy to isolate and difficult to evacuate, so they need to revise the Department of Homeland regulations that have not changed for 16 years from 2004.

[Professor In Sejin / Department of Fire Safety, Woosong University: A tunnel is a place where you can reach a dangerous situation if an accident occurs. Because it's sealed. Under the assumption that it operates well, I think it would be better to strengthen the installation even if the standard is lowered.]

In fact, France is obliged to install a smoke control facility in tunnels 300m and Germany 400m.

Seoul will also install a ventilation system in all tunnels over 500 meters by 2022.

(Video coverage: Hwang In-seok, Lee Yong-han, Kim Dae-su, JTV, Lee Dong-nyeong, JTV, Video editing: Kim Jong-tae)

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