italy, viareggio, train crash and explosion

8/10/2019 ITALY, VIAREGGIO, TRAIN CRASH AND EXPLOSION

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A freight train composed of 14 tank wagons owned by GATX

Rail, each having a nominal capacity of 46.7 T of LPG ,

Derailed at about midnight, as it was travelling through

Viareggio, on 29thJune, 2009

Viareggio is one of the highly populated cities in Italy and since

it was midnight people were sure to be at home

WHAT HAPPENED


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The vessel of the first tank wagon after the engine

breached after overturning and caused a flash of LPG

The flashing LPG spill caused the formation of a Gas

Cloud and possibly of a boiling pool.

WHAT HAPPENED


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DAMAGE TO HUMAN

killed 31 people from fire. 2 due to shock.

36 injured of which 14 seriously injuredwith severe burns.

The condition of the bodies is such that itwas very difficult to identify them.


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DAMAGE TO PROPERTY

collapsed five buildings and set fire to a vast area.

Homes crumbled or burned, killing residents asthey slept.

About 100 people had lost their homes and a total

of 1,000 were evacuated as a precaution


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WHAT WENT WRONG

reason for explosion


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DIRECT CAUSE

The derailment was caused by the rupture of one ofthe wheels axes of the first tank wagon

Direct cause:mechanical failure of atank car and a loss of

containment


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A concurring cause of the accident is thepossible role of the I-shaped stake in generating

the breach in the overturned tank-car.

DIRECT CAUSE


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Detail of broken axis

FATIGUE RUPTURE-WAGON AXIS

The rupture occurred in the part

connected to the wheel, with a

deep and thin fracture. The

rupture section appeared

smooth on more than 90% of the

surface, with traces of rust.


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WHAT WENT WRONG

All tank-cars used for the rail transportation of

hazardous substances in Europe should undergo the

RID regulations

Every 5 years the tank wagons should undergo a

mandatory maintenance that include X-ray

inspection of wheel axes.


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Indicate that the wagon car underwent

maintenance operations in March 2009

But the crack on the wheel axis was

possibly not detected.

WHAT WENT WRONG


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WHAT WENT WRONG-FLASH FIRE (VCF-VAPOUR CLOUD FIRE)

A LPG cloud of cold and white mist propagating around tharea where the train derailment took place.

No immediate ignition followed the release. The engine drivers

had the time to shut down the engine. After about 3 min an Ignition was occurred reasonably caused

by a combustion engine of a car or of a motorbike

The CC-TV cameras recorded a single, long flash.

No damage due to external overpressure was identified, thusthe cloud combustion may be classified as a flash fire.


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LESSONS LEARNT

Flash-fires due to delayed ignition of a vapor cloud

following a tank-car rupture have caused in the past a

number of severe accidents.

It could be concluded that past accident analysis

evidenced that flash-fires are a well-known final

scenario caused by the leak of flammable liquefied gases.


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LESSONS LEARNT

The derailment was possibly caused by a

fatigue-type rupture.Speed was a key-factor causing the crack-

maximum speed of 100 km/h was allowed for thederailed train


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Maintenance

Proceeded

Recognition of

the crack

No Break

down of the

Axel

Not Hitting on

I shaped Stake

Not punctured

the tank

No Formation

of the Vapour

Cloud

Absence of

Ignition Source

EVENT TREE ANALYSIS

YES

NO

NO

NO

NO

NO

NO

NO

YES

YES

YES

YES

YES

YES

NO

NO

NO

NO

NO

YES

YES

YES

YES

YES

YES

NO


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PREVENTIVE MEASURES

1. Revision of maintenance procedures required by RID

regulations

- Maintenance is effective

- It is properly carried out

2. Derailment Detection Device (DDD)

- Informs the engine drivers of the derailment


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PREVENTIVE MEASURES

3. Specificspeed limitations

- To trains carrying hazardous materials

- When crossing populated areas

4. Removing Stalks and other objects from railway

lines

-Avoid punctures in overturned vessels


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ANY QUESTIONS??

italy, viareggio, train crash and explosion

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