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Children's stunted lungs show recovery in ultra low emission zone

bbc.com

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Re: Children's stunted lungs show recovery in ultra low emission zone

#91

Post by goobatrooba »

bcraven wrote: post #67
theplumber wrote: post #56

Earlier quoted context omitted.

I remember I’ve read somewhere that jogging is actually net harmful for health in the city due the air pollution.

https://www.telegraph.co.uk/news/health/news/10817787/How-ch... Generations of men have been taught that when walking with a woman on a pavement, they should always take the side closer to the road allowing her to keep further away from the traffic. But Dr Iarla Kilbane-Dawe claimed that Londoners should avoid walking too near the kerb because on busy streets, air pollution can be up to a third higher than on the ins…

So in effect, if you want to be the chivalrous man (which no one forces you to be) you still should choose the roadside side of the pavement.

Re: Children's stunted lungs show recovery in ultra low emission zone

#93

Post by walthamstow »

nullify88 wrote: post #34
glenngillen wrote: post #15

Earlier quoted context omitted.

I've not lived in London for more than a decade. I always thought the black snot was from the Tube. Is it not?

I lived on Upper Street in Angel, London by some traffic lights and there was always a layer of black dust inside. I assumed it was brake particulate.

Every house inner London is covered in black soot from the days of coal fires. Have you ever seen one after it's been sandblasted?

Re: Children's stunted lungs show recovery in ultra low emission zone

#94

Post by Symbiote »

masklinn wrote: post #58
jimbob45 wrote: post #7

Earlier quoted context omitted.

That doesn’t solve brake and tire particles. Although…rail might solve those?

> That doesn’t solve brake and tire particles. Regen braking means significantly less brake dust, especially at city speeds and with blended braking. > Although…rail might solve those? Trains still have brakes. Some can regen brake but because they usually don’t have batteries they need the rail or overhead gantry to support inputs. But on a passenger-mile basis, I expect an electric train produces essentially no par…

The usual brake on a train that can't do regenerative breaking is a big grid of resistors to dump the energy as heat.

It's much less wear and tear than friction brakes.

https://en.wikipedia.org/wiki/Dynamic_braking

Re: Children's stunted lungs show recovery in ultra low emission zone

#96

Post by vkazanov »

jabl wrote: post #69
smashah wrote: post #36

Earlier quoted context omitted.

Pretty sure that's due to the tube.

What's so uniquely bad about the tube in London? Poor ventilation and brake dust?

Its the oldest metro in the world. An achieviement, yes, but in old stations ventillation is crap, materials are poisonous, etc.

Re: Children's stunted lungs show recovery in ultra low emission zone

#97

Post by itsyonas »

herbst wrote: post #92

When I talk about health implications I often end up saying "but it's less bad than living next to a street" which statistically many things we spend time optimizing about are. However most people live next to a busy street ...

The street isn't the problem. Cars and trucks are. If those streets were filled with people walking, cycling, etc., the health penalty of living next to one would vanish overnight.

Re: Children's stunted lungs show recovery in ultra low emission zone

#98

Post by herbst »

itsyonas wrote: post #97
herbst wrote: post #92

When I talk about health implications I often end up saying "but it's less bad than living next to a street" which statistically many things we spend time optimizing about are. However most people live next to a busy street ...

The street isn't the problem. Cars and trucks are. If those streets were filled with people walking, cycling, etc., the health penalty of living next to one would vanish overnight.

Ok that's not what I consider a "busy street" but I get your point, need better wording there.

Re: Children's stunted lungs show recovery in ultra low emission zone

#100

Post by masklinn »

jurip wrote: post #71
masklinn wrote: post #58

Earlier quoted context omitted.

> That doesn’t solve brake and tire particles. Regen braking means significantly less brake dust, especially at city speeds and with blended braking. > Although…rail might solve those? Trains still have brakes. Some can regen brake but because they usually don’t have batteries they need the rail or overhead gantry to support inputs. But on a passenger-mile basis, I expect an electric train produces essentially no par…

I believe at least subways tend to have lousy air: https://engineering.nyu.edu/news/subway-air-pollution-dispro... But I expect it's much better in open-air rail systems.

I was thinking open-air yes, tunnels do indeed have major issue. With pollutant concentrations, road tunnels are the same (https://www.sciencedirect.com/science/article/abs/pii/S13619...).

For all that I did not care for them originally this is probably something full-height platform screen doors help with, assuming the trains themselves are also filtered that would keep the pollutants clear of drivers and users, although it does not exactly resolve the question of managing their presence in the tunnels themselves (and track / tunnel maintenance personnel should probably already be wearing respirators if not full breathing apparatus), and I could see things get pretty dire in case of breakdowns.

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