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Re:Tesla: Third Model S fire in past two months by tanglesome on Thursday November 07, 2013 @01:37PM (#6691352)
I wonder how many gas-fueled car fires have there been in the last two months... just asking.
Re:Tesla: Third Model S fire in past two months by jggonz on Thursday November 07, 2013 @01:48PM (#6691468)
It appears that in two months, you can expect:

(152,300 fires per year) / (6 months) = 25,383 automobile fires based on data from 2006-2010

U.S. fire departments responded to an estimated average of 152,300 automobile fires per year in 2006-2010. These fires caused an average of 209 civilian deaths, 764 civilian injuries, and $536 million in direct property damage.

Facts and Figures

- Automobile fires were involved in 10% of reported U.S. fires, 6% of U.S. fire deaths.

- On average, 17 automobile fires were reported per hour. These fires killed an average of four people every week.

- Mechanical or electrical failures or malfunctions were factors in roughly two-thirds of the automobile fires.

- Collisions and overturns were factors in only 4% of highway vehicle fires, but these incidents accounted for three of every five (60%) automobile fire deaths.

- Only 2% of automobile fires began in fuel tanks or fuel lines, but these incidents caused 15% of the automobile fire deaths.

Source: http://www.nfpa.org/safety-information/for-consumers/vehicle...

Re:Tesla: Third Model S fire in past two months by 001sky on Thursday November 07, 2013 @01:55PM (#6691541)
about 80% involve cars in parking lots, at rest, in repair shops, etc. So, you need to adjust the data. of the 152k, only a subset [~26k] were on public highways. Once you do this, a tsla now has 3x (300%) the chance of a normal car in catching fire in a highway accident, when corrected for miles driven, etc.

[1] https://news.ycombinator.com/item?id=6499111

Re:Tesla: Third Model S fire in past two months by rattray on Thursday November 07, 2013 @02:05PM (#6691636)
Care to share your calculations? They're quite the reverse of my back-of-the-envelope, which rounds to an egregious degree, and doesn't take into account the subset on public highways or not:

150,000 fires / 250mm total cars in america: ~ .0006

3 fires / 20,000 Teslas (their expectation for this year: ~.00015 (4x fewer fires)

I'm not sure whether we should care that gas cars catch fire in parking lots rather than highways... it seems like a huge concern regardless.

Re:Tesla: Third Model S fire in past two months by 001sky on Thursday November 07, 2013 @02:12PM (#6691681)
You need to adjust your data down to 26k hwy fires and correct for milage driven. For a comparison even to how tesla cites the data, see: https://news.ycombinator.com/item?id=6499111

I'm not sure whether we should care that gas cars catch fire in parking lots rather than highways...

These vehicles are typically not occupied. So from a driver and passenger safety perspective...you really should care.

Re:Tesla: Third Model S fire in past two months by rattray on Thursday November 07, 2013 @02:53PM (#6691959)
Gotcha. Thanks!
Re:Tesla: Third Model S fire in past two months by codemac on Thursday November 07, 2013 @01:43PM (#6691407)
Well let's be specific.

Given a normalization of usage, period of ownership, driving habits, and maintenance: do they have a different rate of fires that is statistically significant.

I don't know the answer, but that's the question you should be "just asking".

Re:Tesla: Third Model S fire in past two months by 001sky on Thursday November 07, 2013 @01:56PM (#6691550)
Tesla is now 3x more likely than a petrol car to have fire on the fwy.
Re:Tesla: Third Model S fire in past two months by whyenot on Thursday November 07, 2013 @02:00PM (#6691589)
Let's do a "back of the envelope" calculation:

Between 2006 and 2010 there were on average 152,300 automobile fires per year [1] so a reasonable estimate for 2 months would be 25,383. There are approximately 19,000 Tesla Model S sedans on the road [2]. If we assume most of those vehicles are in the US, then the Tesla model S represents 0.007469% of the 254.4 million passenger vehicles in the US [3]. One would expect 1.8 Tesla Model S fires in a 2 month period if the chances of a fire are no different for the Model S than other vehicles. But, this calculation doesn't take into account several other mitigating factors, for example if fires are more common in older cars than new cars.

[1] http://www.nfpa.org/safety-information/for-consumers/vehicle...

[2] http://www.engadget.com/2013/11/05/tesla-q3-2013-earnings/

[3] http://en.wikipedia.org/wiki/Passenger_vehicles_in_the_Unite...

[deleted]
Re:Tesla: Third Model S fire in past two months by patrickread on Thursday November 07, 2013 @01:45PM (#6691440)
"minor fender benders"

The second crash in Mexico definitely was not. “This was a significant accident where the car was traveling at such a high speed that it smashed through a concrete wall and then hit a large tree, yet the driver walked away from the car with no permanent injury.”

http://www.bloomberg.com/news/2013-10-28/tesla-says-model-s-...

Re:Tesla: Third Model S fire in past two months by eridius on Thursday November 07, 2013 @01:44PM (#6691420)
> minor fender benders

Where did it say this was a "minor fender bender"? This article doesn't have much detail, but the first fire was a result of a large chunk of metal on the road levering up and stabbing into the engine compartment. I have no doubt that the exact same incidence with a gas-powered car could have had a significantly worse result than the contained fire the Tesla experienced.

Re:Tesla: Third Model S fire in past two months by EpicEng on Thursday November 07, 2013 @01:49PM (#6691477)
Given the fact that the article is vague, you should definitely "have doubt", but you're right; I was thinking about the first crash. I overstated that by a mile.
Re:Tesla: Third Model S fire in past two months by 001sky on Thursday November 07, 2013 @01:40PM (#6691386)
FYI only ~2% of auto fires involve the fuel system.[1]

If this fire was battery related, we are now at 100% for TSLA

[1] On public highways.

Re:Tesla: Third Model S fire in past two months by bastawhiz on Thursday November 07, 2013 @01:53PM (#6691525)
That's not the fairest of comparisons. It'd be like saying only 7% of jet crashes happen because of a malfunction in the vicinity of the cockpit but 100% of hot air balloon crashes happen because of a malfunction in the vicinity of the cockpit. Just because the concentration of failures is on one component doesn't mean the component if generally defective; in this case it just (potentially) means there's fewer components.
Re:Tesla: Third Model S fire in past two months by 001sky on Thursday November 07, 2013 @02:00PM (#6691588)
no, you are missing the point. the battery is not defective. the battery system is just more likely to catch fire when compromised. petrol fuel systems are not only more protected from damage (typically, behind the second axle) but also just less likely to catch fire (on the hwy)[1]. You generally need both a puncture and a spark. A battery shorts with Just a puncture by something metal (usually), so there is one less logical step.

[1] High-pressure fuel lines are well protected outside of the battery, also (they are small) en route to the intake manifold. Here, the EFI rail is also behind the engine block and not likely to take a direct impact. Even then, they are flexible and not likly to break (they would bend).

Re:Tesla: Third Model S fire in past two months by darrenkopp on Thursday November 07, 2013 @01:41PM (#6691392)
There was an earlier thread today that did the numbers on this: https://news.ycombinator.com/item?id=6689591
Re:Tesla: Third Model S fire in past two months by w0utert on Thursday November 07, 2013 @01:51PM (#6691497)
>> I wonder how many gas-fueled car fires have there been in the last two months... just asking.

Contrary to popular belief (and maybe common sense), gas-fueled cars rarely catch fire because of the gas in the tank. You'd need a gas leak and some form of external ignition, which rarely occur together. Apparenly with a battery-powered car, all you need is piercing damage to the battery.

Re:Tesla: Third Model S fire in past two months by puma1 on Thursday November 07, 2013 @01:51PM (#6691507)
Yea but there aren't that many Tesla's on the road are there?
Re:Tesla: Third Model S fire in past two months by sjtgraham on Thursday November 07, 2013 @01:39PM (#6691376)
pro rata