Luton Airport flights suspended after large car park fire

In what ways is this fire different from the Stavager fire? You keep talking about the "hallmarks" or the "stamp" of EV vs diesel fires, what are they?

There were some reports of the Stavager fire being started from an EV. But all of those were by people who simply don't know much. Once the fire department released the official report (not someone standing at a lectern) it provided evidence of it being a diesel fire and specifically which car. This report is not going to change.

You have an unsupported assumption, that diesel cars never caused fires. Car fires are seldom reported. Even when they are, unless they are near us, or cause a lot of damage, we don't pay much attention.

I have no idea what you are talking about comparing the diesel car to the others. The point is the fire started in the diesel car. Had it not ignited, none of the other cars would have been set on fire. So, what is your point???

Tanks use diesel because it's less likely to explode in battle.

I wonder when we'll have electric tanks. Well, we sort of do already.

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I understand the car was identified as a diesel-electric hybrid Range Rover and there is video online showing it on fire before the conflagration spread to other vehicles.

In 50+ years of motoring I've come across several petrol vehicles that caught fire, but never any diesel ones. What would be the mechanism that raised the diesel above its flash point and then ignited it in air in sufficient quantity to cause the rest to catch fire? If you pour diesel on concrete and chuck a match on it, the match goes out.

Nope. I mean the Luton airport carpark fire which destroyed 1,500 vehicles and the car park itself. It's been identified as a Landrover Discovery Sports SUV *hybrid* with a PHEV plug-in lithium battery under the front passenger seat, so I think we can guess where all those flames came from now. So there we go, the MSM got it wrong again. Plus a bunch of the usual trolls on this newsgroup.

Yes. Many years ago, a friend was worried that fumes from kerosene used in the basement to wash car parts during repair might travel to the gas-fired water heater and go off, launching the house over the moon.

So I set up a little demonstration, pouring a little kerosene into a shallow dish, lighting a match, and moving slowly towards the dish.

She saw this and started to scream no no no ...

Which ended when the match went out when it was wetted, all without drama. Lit another match and held if just above the kerosene surface for a minute. No reaction.

Her objections ceased.

For the record:

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Joe Gwinn

Cursitor Doom is convinced of it. More rational people aren't.

What burns in EV fires is primarily the organic liquid electrolyte in the cells. It can't get out until the cells burst, and they have to get pretty hot for that to happen. The carbon and the lithium in the cells also burns, but it isn't liquid and doesn't flow around as easily as the electrolyte does.

You can guess. Saner people wait for more detailed information.

As Cursitor Doom is convinced they do regularly. It wouldn't be the main stream media is most people shared this delusion.

Cursitor Doom likes his news to be utterly fatuous and the main stream media don't see him and his ilk as numerous enough to be worth catering to. The Murdoch media has a different attitude - it's cheap to provide gullible twits with the fantasies they like, and advertisers like advertising to them.

That's not true. A fully discharge cathode (full of Li ions) without electrolyte can ignite like a rocket. I have done it a few times, just for fun and demo.

Rocket fuel contains it own oxidiser and can be ignited in a vacuum. A fully discharge cathode doesn't and shouldn't.

It can burn fast, but it need oxygen from the air to oxidise. Presumably if you get it hot enough some of the constituents will volatilise to form a burning jet, but while that may look like a rocket, the mechanism is different.

Lithium oxide (lithium ions) shouldn't burn any more that caustic soda (sodium ions) does. The graphite is more flammable,

Lithium ions in cathode may not be same as Lithium oxide. Lithium particles are highly combustible, on it's way to become Lithium oxide.

I am sure dead Lithium batteries can ignite like firework/rocket.

Lithium atoms have only two oxidation states. There's no intermediate state between lithium metal and a lithium ion. When you get further up the periodic table you get more choices - ferric (Fe3+ )and ferous (Fe2+) salts of iron are an obvious example,

They may look like a firework or a rocket to you, but gunpowder has a built-in oxidiser, and a discharged lithium cell doesn't. It may burn spectacularly but that's the end of the similarity. Telling somebody who has a Ph.D. in chemistry that you are dead sure about something chemical rarely works out well.

Flyguy doesn't seem to have noticed but he's as far gone as a a.

My previous (new) diesel car was on a manufacturers recall for a fuel pump fault that had the potential to cause a fire so it does happen. It also happens to high power diesel tractor units on HGVs.

Once it is alight then diesel is more effective at spreading fire than petrol. Petrol has a tendency to flash over explosively and quickly whereas diesel burns steadily and flows along the ground. Liquid fire.

If you want to use an accelerant on bonfire night and live to tell the tale you should use paraffin or diesel (and be very careful).

People who use petrol tend to end up in A&E if they survive. Vapour pressure is too high so it tends to form an explosive fuel air mix.

I think I have seen half a dozen vehicles on fire by the roadside. Two of them we were the first to call in to 999. Roughly one every 100k miles. The last one was this summer and spectacular a diesel tanker on fire and it closed the M1 destroying lane 1. This one on the S bound carriageway (shown after they had got it under control).

We were headed north and the incident had only just begun so were passed by a fire engine doing a bat out of hell act. It took a few hours to get it back under control with the motorway closed in both directions.

I wouldn't like to bet on that. When we lived in Belgium we went around various houses to choose which one to rent. Most have the oil tank and boiler in the basement and one had an inch of kerosene on the floor with the boiler merrily running. The flowstop interlock had failed and the whole house reeked of kerosene. We couldn't leave quickly enough.

Kerosene/paraffin is relatively safe to handle. But people have been killed cleaning parts with petrol on the kitchen table.

Vapour pressure is too low to ignite the fumes but once it is properly alight you have liquid fire that can flow downhill. Car tyres and plastic mouldings probably provide the necessary wick to allow it to sustain burning in the initial phase. Once a car is alight you need a proper fire extinguisher to put it out.

Water ones are only any good for breaking down locked firedoors (at least that was what I was taught back in the 80's). The fire training course for solvent and chemical fires was impressive. Dry powder will take out a car fire provided that you aim at the base of the fire. CO2 might if you are very lucky. Most people aim too high partly from the the recoil of the discharge and a tendency to point it at the flames.

The ultimate car fire knock down is no longer allowed a small single hand holdable BCF canister could take one down in seconds. Banned now under the Montreal protocol but not back then.

ISTR it is still used in aircraft for critical fire suppression systems.

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I have used a BCF extinguisher on a car fire, so I know from experience that it works. (The fire turned out to be an attempted insurance fraud, so my efforts weren't appreciated by the owner)

I cannot see the logic of banning BCF in extinguishers, I would have thought discharging one extinguisher would do far less environmental damage than the toxic combustion products of an uncontrollable car fire.

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Yes - however, it is much more difficult to light in the first place. It either needs something that can act as a wick or some sort of pre-heater which can raise the liquid to flash point. Petrol funes only need a tiny amount of energy to start a fire but diesel needs large amounts of energy over a period of time.

When it comes to accidental fires, diesel is a long way down the list of potential starting materials (below cotton and paper).

Not unless the ground is absorbent like a wick or so hot from radiant heat that the diesel is raised above its flash point.

??? It does? The flash point of diesel is between 52 and 96 °C, so not at all hard to achieve if it touches an ICE.

No body cars where it is on the list when it catches fire. Diesel is the fuel used in the vehicle that started the garage fire in Stavanger.

I don't think you understand what a flash point is. If the diesel fuel is burning, and rolls across the ground, the flame will follow the fuel. A flash point is only about raising the temperature enough that the vapors will burn from a source of ignition. In a pool of burning diesel, the flame has enough heat to assure the flame will spread. If you don't believe me, stick your thermometer where the diesel will flow over it, and ignite the beginning of the diesel flow. Tell me how hot the thermometer gets.

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I have just tried the following experiment:

The air temperature is 18C and there is hardly any wind. I poured 5ml of diesel onto a dry paving slab and tried to light it with a cigarette lighter - it wouldn't light.

I tried to light it with a match - it wouldn't light.

I made a criss-cross pile of 6 matches, soaked them in diesel and set fire to them. The matches burnt for a short while and then went out - the surrounding pool of diesel didn't light.

I squirted 2ml of isopropanol into the middle of the spreading diesel pool and lit it. The isopropanol burnt away, the charred remains of the matches and some of the diesel burnt with it, leaving a dry patch on the slab but the fire didn't spread beyond the boundary of the isopropanol pool. Most diesel components evaporate around 200 - 300C, so the dry patch suggests that the surface of the slab under the burning isopropanol was at least that hot.

Practical experiment trumps theoretical bullshit.

It proves the point - even with an inch of kerosene on the floor near the boiler, the house didn't fly over the moon.

But what a cleanup job it must have left. I'd assume that steam would be required.

Absolutely; this is what she feared. But she didn't know the difference between gasoline and kerosene.

When I was a kid, I cleaned things in gasoline, but this was always done outside. As did all my grease-stained friends.

Yes.

In the report on the Stavanger fire by the fire safety authorities they commented that modern cars had a significant amount of fuel value due to plastic components, in addition to the fuel.

BCF (Bromochlorodifluoromethane) is known as Halon in the US.

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For lack of any real alternative. I agree with Liz T that outlawing Halon was a mistake.

Circling back to the original question, the devastating fires in the parking structures at Stavanger and now Luton airports, the key is not what kind of car started the fire (both may be diesels), it's what happened just after.

Joe Gwinn

Well done, Liz. That's what's all too often missing from this newsgroup: logical, clear-headed thinking.