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Dust from car brakes more harmful than exhaust, study finds

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Re: Dust from car brakes more harmful than exhaust, study finds

#281

Earlier quoted context omitted.

> Transportation that is not powered by one's own muscles can never be virtuous. ... unless said transportation puts users in close physical proximity to strangers, some of whom are loud or dangerous. Such transportation is very virtuous: the more numerous, dangerous, or annoying the strangers, the more virtuous the transportation. This exception is not applicable to transportation that flies or floats.

> loud or dangerous This seems to be mostly a US problem, I only really see people from the US worried about this... As someone from the UK who travels on two trains and a bus both ways (6 journeys total) most weekdays to university, I never had any problems with other passengers, I guess very occasionally there might be a loud baby or something but then you can just put headphones in, and the worst thing that ever h…

There are entire neighborhoods in the US where you are advised to keep your doors locked and never to stop at a stop sign or red light.

Re: Dust from car brakes more harmful than exhaust, study finds

#282

Earlier quoted context omitted.

Which is 4,500-5,500lbs curb weight, just FYI.

Which comes out 200lb lighter than a Toyota Highlander hybrid.

From what I understand, Ford did some really significant work on lightening the F150 maybe 5+ years ago, I was surprised at how light they are. Looks like a Tesla Model S for comparison is $4,300-5,000lbs.

Re: Dust from car brakes more harmful than exhaust, study finds

#283

Earlier quoted context omitted.

Every study I've seen concurs that EVs chew through tires faster than their equivalent ICE vehicle, and generate more tire particulate matter accordingly. The reasons (torque and weight) are unambiguously greater in an equivalent EV vs ICE. EVs do generate lower brake particulate matter, by virtue of not using them as much (otherwise they'd also be prone to generating more in a (faulty) per-engagement direct comparis…

https://www.ch.cam.ac.uk/news/%E2%80%98illusion-truth%E2%80%...

I agrée with this and have ripped claims about the pollution here on HN before, but there is SOME pollution, and it is necessarily worse for EVs vs ICE for the reasons above.

Re: Dust from car brakes more harmful than exhaust, study finds

#284
post #213

Earlier quoted context omitted.

There was that whole study with some additive in tire compounds, killing whole rivers of salmon until they figured out what it was

EVs can be pretty bad for tire wear, not just due to vehicle weight, but the amount of torque available (and consistently available) that leaves most ICE vehicles in the dust. Depends on driving style of course

Sounds like emission standards need to be updated to include everything coming off a vehicle, not just out of the tail pipe.

It would incentivise clean disk materials and regenerative braking.

Re: Dust from car brakes more harmful than exhaust, study finds

#285
This sounds similar to claims that cancer rates are increasing.

Which is to say that it may be true but it’s a symptom of improvements. Cancer rates are increasing because people are living longer and dying less of other things. Similarly, a huge amount of work has been done to reduce the harms from car exhaust, and modern vehicles burn really cleanly. It’s no surprise that other factors start to become relatively more important.

Re: Dust from car brakes more harmful than exhaust, study finds

#286
post #212
post #88

The Yale article and the paper both highlight the fact that EVs use regenerative braking and produce less dust. I was worried that this was a rehash of the astroturf campaign from a few years ago focusing on EV weight and how that was so bad for the environment because of tire and road wear. Unfortunately you need to read through the whole thing (instead of the headline and a few paragraphs) to see that information.

Granted, I would still rather them designed for lighter weight. But that’s a separate issue w suv culture which is bad for society and environment in general. Totally would buy a 3000 pound EV around the size of a euro hatch.

Agreed about SUV culture. American consumers demand giant cars. It is a safety arms race and also cultural preference.

Re: Dust from car brakes more harmful than exhaust, study finds

#287

Earlier quoted context omitted.

Rubber still wears off tires though so that may be worse or not for heavier vehicles

Worried about heavy vehicles? The best selling vehicle is the Ford F-series.

I would think tire wear is a function of both weight and torque. The worst offender would be a Hummer EV.

Re: Dust from car brakes more harmful than exhaust, study finds

#288
post #215

Earlier quoted context omitted.

Not significantly. Otherwise they’d get hot and work less well. Pads ride very closely to the disc so that road stuff can’t get wedged between the surfaces, and so that you don’t waste break pedal travel just getting the pads close to the surface. Well adjusted drum brakes should be arranged almost exactly the same way. From https://mechanicswizard.com/how-close-should-brake-pads-be-t... : > Typically, the optimal ga…

Are you familiar with how disk brakes on a car operate? They’re essentially a hydraulic piston clamping the brake pads against the rotor. When you let off the brake pedal, the pressure is removed, but there’s not a “retraction” of any kind. So there’s no pressure but nothing is actually making that gap. That article was articulating basically that the piston, when not compressing the brake pads, should not be too far…

Something makes them retract slightly - how they’re seated in the caliper retaining clip maybe I’m not sure because trivially you can take the wheel off and press the brake and see it.

It’s even easier to see on a bicycle with hydraulic discs.

Re: Dust from car brakes more harmful than exhaust, study finds

#289
post #52

This is the regular current taboo. Micro-dust from tires and brakes contributes to half of an ICE vehicle’s pollution, with the other half coming from exhaust emissions. The amount of this micro-dust scales with a power of the vehicle’s weight, typically between the square and cube for cars, and up to the fourth power for heavy trucks. EVs are 30–60% heavier than their ICE counterparts. Assuming all other factors rem…

> This does NOT even include the environmental impact of battery production and electricity generation

Okay so if we're veering off particulates here anyway, why ignore that electricity generation is actually a whole lot cleaner than burning contemporary fuels?

Maybe better not to rehash the obvious, I just wanted to point out that there's more to it than downsides

Re: Dust from car brakes more harmful than exhaust, study finds

#290

Having lived next to a semi-main street through a smallish California coastal city without much rain it is pretty eye opening how much black dirt and junk just coat everything next to the road. Walk down the street and touch a bush or any plant leaf and get a nice black hand in the process. The plants are covered, parked cars get covered and the inside of my apartment was covered. It wasn’t until I moved out that I s…

> Having lived next to a semi-main street through a smallish California coastal city without much rain it is pretty eye opening how much black dirt and junk just coat everything next to the road. One day I made the mistake of leaning against the wall in a TTC subway station while in a white shirt. I didn't realize how much oil, brake dust, and other mechanical grime there was until that moment. I had to go home and c…

"boot the grime of this world in the crotch, dear!"
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