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Luton Airport car park ablaze 8

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MortenA: Get a grip . . . ICE vehicles catch fire many times more often than EV’s.

Is this only anecdotal evidence due to the preponderance of ICE vehicles?

The ‘flashy’ article linked above by you, claims Hybrids are 3X more likely to burn than their conventional counterparts; in a “now debunked” paper. Hardly proving the point.
This article really proves, if you can’t think for yourself, someone else will.
 
BBC are reporting that it started with a diesel car. I wonder if this could be a DPF regen going out of control, as the video they are showing where apparently only a single car is burning makes it look like the car was being driven when it caught fire. See the 16:03 report in their updates:

BBC News: Footage emerges of burning car which may have started blaze

Hoxton123 said:
I have never noticed sprinklers in a UK carpark. No idea about regulations in other countries.

There are a number of multi-story car parks local to me (in the UK) which have full sprinkler coverage, both old 1970s builds and very recent builds, but it's possible that is due to them being underneath or attached to buildings.
 
Yeah, both numbers are meaningless in comparison, without converting them into a representative percentage of their population. It might even be necessary to exclude some old ICE vehicles from the numbers to allow for EVs being a relatively new group.
 
Since most vehicles on the road today are ICE cars, the insurance industry uses a percentage of 100,000 vehicles sold to get meaningful comparisons.

Data from the National Transportation Safety Board, Bureau of Transportation Statistics and recalls.gov shows that overall, lumping EVs and hybrids together compared to ICE cars, more ICE cars caught fire than EVs; 0.3% for EVs and 1.05% for ICE cars.

 
The trouble is that the EV fire is much more destructive.

Also, does this NTSB statistic include EV's that catch on fire during delivery?

What defines a fire? Does it require a total loss of the car?
 
How does those figures work out when the EV starts a fire that destroys hundreds of ICE vehicles?
 
And now we are starting to understand why statisticians love percentages. They don't have dimensions and can be manipulated to say anything.
 
Stand alone parking structures here in Australia don't require sprinklers (from observation). But if the garage is attached to a different class building eg residential/commercial medium/high-rise then it changes everything. The Luton car park seems to be an unlucky outlier.

If you have enough car parks built without sprinklers or other protection then eventually one will go up in flames. In many ways I don't see the engineering failure here. The engineering seems to have worked as intended.

TugboatEng said:
The trouble is that the EV fire is much more destructive.
Is it? ASFIK energy density is significantly lower for EV batteries. The normally stated figures only allow for discharge not complete thermal decomposition, but I'm not aware that total energy released in combustion is more for an EV. (Though energy is just one factor here.)
 
You have asked a very complicated question. This is the best quality paper that I can find that discusses the issue. It documents the watt hour heat generated by a battery fire. I am not ready to offer any interpretation of the information relative o ICE vehicle fires.

Understanding Lithium Ion Battery Fires - OSTI.GOV
 
Another drone picture of the Luton Airport car park .... It seems that the fire was in the "newer" part of the garage

Several levels have collapsed on themselves.... In my opinion, this points to a systematic problem with the design

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MJCronin
Sr. Process Engineer
 
Something to keep in mind when considering the energy released from a Li-ion battery in meltdown. The nominal electrical capacity is significantly less than the total electrical energy in the cells, as they are considered "empty" at around 3.0V (discharge below minimum causes permanent and dangerous damage to the cells by dissolving the copper anode, which replates randomly on recharge). Additionally, there is significant chemical energy available in the electrolyte. I wouldn't want to guess just how much larger the total electrical and chemical energy is in full meltdown, but it's significantly higher than the nominal electrical capacity.
 
I believe the word "apparently" can be taken out. The number plate is visible and it is registered to a 2014 Range Rover with a diesel engine. There was no hybrid or electric version of that car on sale in 2014.
 
According to NTSB, 2017 report, the fire risk of EV is comparable to ICE, or slightly less.
Fast-forwarding three years to the above referenced 2020 data, and something changed. But what?
How did EV’s become ten times less fire prone, in just three years?
I must admit these cars are basically weapons: unstoppable fires and hydrogen fluoride gas,
Whose idea was this anyway?
 
The variety of EVs on the road and the number of EVs on the road now are both vastly greater now than in 2017, and additionally, companies building them now have quite a bit more experience with them now than they did in 2017. Whatever the NTSB wrote in 2017 (Cite it or link it, please) would have been based on preliminary information which is now outdated.

In 2017, the only EVs on the road in appreciable numbers were the Nissan Leaf, and the Tesla Model S. The Chevrolet Bolt was new to market (the troublesome model year was 2019). Tesla went through their share of issues early on.
 
Zooming in on the google street view, exterior steel bolt heads are showing. This indicates that the steel was not covered with fire proofing.
Screenshot_from_2023-10-15_05-53-13_soqbrt.png
(Enlarging the picture in MJCronin's post the interior steel most likely does not have fireproofing either.
Screenshot_from_2023-10-15_05-50-13_nt0e68.png

Had fireproofing been applied, it would have slowed the structural steel temperature rise to the softening point, but might not have delayed the temperature rise long enough for the fire to burn itself out.
Lack of fireproofing on exposed structural steel is not necessary a design flaw, it depends on the building code specification.
 
The "code" apparently says 15 minutes fire resistance. Basically just enough time to allow people to escape.

If it's part of a building that would be different, but a free standing multi storey car park is 15 mins.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
 
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