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Dust from car brakes more harmful than exhaust, study finds

e360.yale.edu

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

#301

Post by perlgeek »

helsinkiandrew wrote: post #3

> researchers grew human lung cells in a lab and exposed them to dust from car brakes and from diesel tailpipes, finding that brake dust caused greater injury to the cells. I couldn’t tell if the study found that car brakes are more harmful than exhausts, or that car brake chemicals are more harmful than exhaust fumes - but that may not be significant because they are produced in less quantities.

I suspect it's even more complicated; if the particulate matter is different in size, the relative amount delivered to a human lung might depend on the distance.

So if you want to model somebody being 10 meters away from the street, you might need to use different ratios than for somebody being 100m away.

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

#302

Post by datavirtue »

kstrauser wrote: post #207
m463 wrote: post #181

Earlier quoted context omitted.

I suspect drum brakes were chosen by the electron pinching EV engineers. They're the only brakes that are friction-free when not applied. Disc brakes rub (and slow the car) even when not applied.

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…

The default for drum is less friction (gap increases, takes more pedal) over service life whereas pads default to more friction (slides gunk up and spring clip faces rust and swell) from failing to retract as well.

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

#304

Post by maigret »

jlnthws wrote: 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…

If you are consistent then, your solution should be to move to another transportation, or to help policy transition. Because bikes, trains and bus are undiscutably better.

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

#305

Post by datavirtue »

lukevp wrote: post #215
kstrauser wrote: post #207

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…

The rotors push the pads away from the surface if the slides and spring clip seats are maintained. I have seen many unbalanced brake systems with uneven pad wear of all kinds due to rust/dust/heat impacting the system.

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

#306

Post by Schiendelman »

uxp100 wrote: post #278
Schiendelman wrote: post #175

Earlier quoted context omitted.

Three or four years ago, yes. Newer EV specific tires don't seem to be wearing faster.

Unfortunately Nissan did not put such a tire on my Ariya. Good range and very quiet but very soft and only 9/32 from factory means lots of people have to replace em after 15 to 20k. I’m replacing earlier given poor snow and rain performance. They can have em back when my lease is up.

Understood, but that's Nissan sucking.

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

#307

Post by Schiendelman »

Scoundreller wrote: post #257
Schiendelman wrote: post #174

Earlier quoted context omitted.

EV specific tires have basically eliminated the difference in tread loss already. And because there's public pressure on this, the toxicity of the materials and tires is decreasing rapidly. Every study I've seen from people pushing on this uses very old information about tires, proving there's a problem really requires updated work taking these things into consideration.

Can I put these EV specific tires on my ICE to get super-duper tread life? (and have the tire companies been conspiring to make tires disposable?)

Yes, and yes. Though with a lower mass vehicle you may have reduced grip.

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

#308

Post by Schiendelman »

rafaelmn wrote: post #190
Schiendelman wrote: post #172

Earlier quoted context omitted.

Regenerative braking has much less tire wear than traditional braking because it's done much more slowly and smoothly. Also, none of these discussions use up-to-date information on EV tires. Consumers aren't willing to replace their tires much more often for an EV except at the high end of the market, tire manufacturers are already making tires last much longer for EV purposes. New designs are already shedding less d…

Teslas eat tires for breakfast. Instant torque and high weight - any benefit you get from regen breaking is not scratching that.

As a Tesla owner, I'm 33k in on a set of all seasons and still in the green on two. You can't move the goalposts like that - the same is true on an ICE sports car.

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

#309

Post by Schiendelman »

rafaelmn wrote: post #208
YZF wrote: post #202

Earlier quoted context omitted.

My model 3 is 5 years old and I'm still on my original set of tires (though in recent years I do put on winter tires for a few months a year). I don't usually drive like crazy (and it's an SR+ which is the least powerful model).

True, and you can do engine breaking and do milder acceleration curves in ICE car and that will significantly reduce the pad/tire wear. But if you drive like, I would speculate, most people do, Tesla will go through tires like a track car (half joking)

Sure, but the same can be said for a performance ICE car.

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

#310

Post by ghaff »

Gibbon1 wrote: post #299
orev wrote: 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.

Just a note. If the manufacturers can get solid state batteries to the point where they are economic then EV's will be as heavy or perhaps lighter than gas cars. Actually a 50% increase in energy density is enough. And solid state batteries have twice the energy density. So likely lighter. Jevons paradox says cheap EV's are maybe not so great. Consider if a cheap car cost a $100k most people wouldn't own cars. They'd…

Many people live in locations where walking, the bus, or subway are never going to be practical and/or do regular activities that need personal transportation. If a car cost $100K I'd almost certainly still own one.
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