Failure Knowledge Database / 100 Selected Cases

Train Fire in Hokuriku Tunnel
November 6, 1972 in the Hokuriku Tunnel
Masayuki Nakao (Institute of Engineering Innovation, School of Engineering, The University of Tokyo)
The late night train “Kitaguni” bound for Aomori from Osaka caught fire while the train was in the 13,870m
long Hoku riku T unnel. Criticism wa s raised at inadequate fireproofing and fire regulations that in structed
operators to stop the train in a tunnel in case of fire. The accident killed 30 people including 1 crew and injured714.
1. EventThe lat e ni ght train “Kitaguni” b ound for Aomori fr om Osaka caugh t fi re while the train was in the
13,870m long Hokuriku Tunnel located in Fukui prefecture. The accident killed 30 people including 1 crew
and injured 714. Th e cause of death was carbon monoxide poisoning, not death by fire. Photo 1 is a press
photo of the accident.

Photo 1. Burnt-out Dining Car and Rescued Passenger [1]2. Course
A din ing car in th e late nig ht o utbound train “Kitaguni” caught fire while the train was in the Hokurikutunnel. The dining car was the 11th of the 15-car train. At around 1:10 a m, pass engers reported fire to a1

Failure Knowledge Database / 100 Selected Cases
train c onductor. The tr ain cond uctor immediately arranged an emergency stop, and at 1: 13 a m, the tr ain
stopped at 5.3km from the Tsuruga Exit (Figure 1).

Figure 1. Hokuriku Tunnel

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Figure 2. Schematic Illustration of Fire Site (Hokuriku Tunnel) [1]
Two of the train crew tried fire extinguishers to s top the fire, bu t the force of the fi re did not abat e. Thecrew then decided to dis connect the b urning car and evacuated the tr ain. At around 1:24 am, railcars wereseparated between 11th and 12th by 60m (Figure 2).
At 1: 29 am, the cr ew requested help to t he ex it stat ions of th e tunnel, the I majo Station and the Tsuruga
Station. They attempted to disconnect the 9th and the 10th cars when a power failure on the outbound line
brought the train to a stop in darkness at 1:52 am.
The long tunnel made the evacuation of 760 passengers difficult. The inbound train “Tateyama 3”, which
was made a stop due to the tunnel fire at that time, picked up some of the passengers and carried them toTateyama Station. Many tried to evacuate by foot, and some were returned to the railcars because of theheavy smoke in the tunnel.
Rescue trains were driven in from the Tsuruga Station at 2 :43 am and at 6:4 3 am , bu t th e h eavy s moke
prevented the rescue crew from approaching the burning train. They picked up the passengers in the tunneland returned to the station. It was 14:00 when the r escue effort made all live passengers and crew escape
the tunnel.
The f ire claimed lives of 29 pass engers and 1 cr ew, all d ied of s moke inhalation. 714 w ere injured. T he
cause of death was carbon monoxide poisoning, not death by fire.
3. Cause(1) The direct c ause o f the f ire is in disp ute. Different acc ounts r eport it to b e a cigarette but t or acoal-cooking stove.
(2) The flammable material of the railcar contributed to the quick spread of the fire.
(3) The operations manual instructed an emergency stop in a tunnel, regardless of the tunnel length.
(4) The tunnel was not prepared for the possibility of fires.
At the time of the accident, the Hokuriku Tunnel was not equipped with fire safety measures. It had
inadequate ventilation, relying on natural ventilation brought by passing trains. Radio transmission did
not work inside the tunnel, an d t he rai lway p hones installed every 30 0m were the only lin es ofcommunication av ailable. The tunnel did not h ave a powered ve hicle that can run in case o f powe r
failure. In spite of repeated warnings from the local fire department, the Japanese National Railways(current Japan Railway s) had made n o improvement but sim ply r esponded that they will review thefire safety measures.
4. Immediate Action
JNR aborted all dining cars o f the OSHI -17 model that spread the fire i n t his accident. Thi s resu lted intermination of dining services in all express trains.

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Failure Knowledge Database / 100 Selected Cases

5. Countermeasure(1) JNR employed fire retardancy for its new models. New railcar models equip incombustible material,
flame-retardant structures, fire extinguishers and emergency lights.
(2) The rain operations manual were modified by requiring the train to move out of the tunnel rather thanstop immediately after a fire breaks out in a tunnel.
(3) JNR announced strengthened fire r egulations and safety measures for long tunnels. The improvement
included as signment of p owered res cue vehicles, installa tion of smoke co ntrol equipment a ndevacuation co rridors. In response to t his t unnel fire , the S eikan T unnel als o has parallel ev acuation
corridors. For r oadway tunne ls, th e Nih onzaka Tunnel fire l ed many i mprovements in t he f ire s afetymeasures.
6. Summary
The accident claimed many deaths and injuries because of the emergency stop of a railcar in flame, which
made fire fighting and evacuation difficult. The train operators made this emergency stop simply following
the obsolete operations manual that required the train to stop in a tunnel in case of fire. This fire regulation
was created when tunnels were much shorter. If the operators assessed the situation quickly and let the train
travel out of the tunnel, there would have been le ss injuries and deaths. If the operators had acted against
the safety regulations m ay be held cri minally accountable f or any damages, b ut the accident s cale musthave been minimum.
If a tunnel fire occurs on a steep gradient, the tunnel acts like a chimney sucking cold air in on one sidewith the intense heat and smoke leaving on the other. As a result, the force of the fire as well as the damage
to the accident multiplies. This chimney effect was seen in the 2003 subway fire happened in Daegu, SouthKorea.
7. Knowledge(1) Operators cannot blindly follow safety plans given in the manu al in emer gency situations. They musttake an appropriate action for the given situation. It may be difficult for operators to remain calm, but aproper training will raise the safety consciousness of operators so th at they can always give reasoned
judgment even under unexpected circumstances.
(2) An o perations manual s hould provide saf ety plans for various

t ypes of accidents and t heir

recommended recovery procedure based on the analysis of various experimental tests.
(3) It is not safe to simply apply exis ting saf ety me asures to n ew ser vice sy stems. Safety measures andequipment need to always be updated, as they should have been in this accident for longer tunnels.
(4) Fire safety measures are usually taken in wake of an accident.
8. Background
During the p eriod of postwar s ocial and economic reconstruction, national and local o rganizations
4

Failure Knowledge Database / 100 Selected Cases
cooperated t o de velop a fundamental pl an f or the use, de velopment an d c onservation of t he l and, a nd
formulated the Comp rehensive Natio nal La nd De velopment Act in 1950. Th e Hoku riku T unnel was atunnel for a doub le track rail way completed on Nov ember 14, 19 57 when the H okuriku M ain Li ne w as
electrified. The 13.87km-length tunnel was the 6th longest tunnel in the world, the second in Japan at thattime. Whi le the tunnel enhanced t ransportation capacit y, it elim inated the o ld u nelectrified s ingle-track
railway t hat had series of steep

slopes . Mo re tunnels were con structed aft er for mulation of theComprehensive National Development Plan in 1962 in an at tempt to moderate the rural depopulation andreduce the income gap between central cities and outlying regions.
9. On the SideDue to the difference in atmospheric pressure, many tunnels have air draft from one exit to the other. A firein such tu nnels in duces a c himney effect, mul tiplying the force of the f ire. The long road tunnels in theAlps are equipped with air forced ventilation systems that feed and exhaust air forcefully from the exits toreduce air draft. A malfunction in the ventilation system or an operation al error wil l fail to stop the quick
spread of fire, as was seen in the 1999 fire in t he Mont Blanc Tunnel. In th is 1999 fire, while the French
company operating the tunnel maximized the air exhaust power immediately after a transport truck caught
fire in t he tunnel, t he I talian company ma ximized the air fe ed powe r fo r 2 0 minutes. A s the re sult, 3 0vehicles were burned in the accident (Figure 3).

Figure 3. 10 km or Longer Tunnels in the Alps (Road/Rail and the Opened Year)5

Failure Knowledge Database / 100 Selected Cases

References[1] Yotaro Hat amura (Edit or), Jissai-no Sekkei (Practical Design) Re search Foundat ion (1996) Zoku-Zoku
Jissai-no Sekkei (Practical Design III), The Nikkan Kogyo Shimbun, LTD.

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