Taipei, May 8 (CNA) The Taiwan Area National Freeway Bureau on Tuesday rejected a range of speculations by drivers and academics about the cause of a fatal accident in the Hsuehshan Tunnel on Monday, saying failure to observe safe driving practices was the main problem.
It is much more important for drivers to maintain a safe distance from the vehicles in front of them than for authorities to lower the speed limits, the bureau said.
The bureau was responding to accusations by academics that gradual increases in the speed limits in the 12.9 km long tunnel, from 70 kilometers per hour in 2006 to 90 kph in 2010, was the main cause of the collision that resulted in a deadly fire. Two people were killed and 31 others injured in the accident.
The fire erupted when a passenger bus rear-ended a car in a line of vehicles that were trying to avoid a truck in front of them that had a tire blowout, according to the National Freeway Bureau.
The bureau said the tunnel was designed to accommodate a speed limit of 90 kph, and that most automobile collisions were caused by drivers' failure to maintain a safe distance from the vehicle in front of them.
Small vehicles driving in the tunnel at a speed limit of 90 kph should keep a distance of 45 meters from the vehicle in front, while large vehicles should maintain a distance of at least 70 meters, the bureau said.
Fire hydrants, which are installed 50 meters apart along the tunnel, can be used as safety distance guides, the bureau said.
Responding to drivers' claims that the tunnel traffic control center's safety warning came five minutes after the accident, the bureau said the records of the Pinglin traffic control center showed the announcements were made one minute after the accident at 1:28 p.m.
As for why the emergency escape shafts were filled with thick smoke, the bureau said as people fled in panic some forgot to shut the outer doors of the passage way to the escape shafts, which allowed smoke to fill the shafts.
The bureau will consider redesigning the tunnel doors so that they will close automatically, said Hsu Cheng-chang, head of the bureau's Northern Region Engineering Office.
The bureau also responded to complaints by drivers that it took the tunnel traffic control center a very long time to clear the smoke, saying a specific procedure has to be followed in clearing smoke to increase the chances of survival in the tunnel.
It took around 41 minutes to extinguish the tunnel fire and 37 minutes to discharge the smoke in the tunnel, which is about the same time achieved in fire drills, the bureau said.
However, New Taipei City Mayor Eric Chu said emergency drills tend to be overly optimistic.
Chu suggested that the relevant government agencies work on training and preventive measures in their drills.
The New Taipei City Fire Department, which assisted in putting out the tunnel fire, recommended that the bureau ensure sound safety measures before opening the tunnel to large vehicles, especially those carrying inflammable loads such as natural gas and oil. Currently, the tunnel is closed to large vehicles other than buses.
Cases abroad have shown that when vehicles loaded with hazardous material are involved in accidents, it not only causes heavy casualties, it is also makes firefighting difficult and damages the tunnel structure, a fire department officer said.
The department recommended that the bureau reevaluate the tunnel safety mechanisms, invite fire experts to conduct safety checks, and re-inspect the firefighting equipment.
(By Sunrise Huang, Shwu-fen Wang and C.J. Lin)