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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

#271

Post by Aurornis »

energy123 wrote: post #102
Aurornis wrote: post #77

Earlier quoted context omitted.

Getting rid of the VOC source, if possible, is much easier than trying to filter it. > Those 2-in-1 filters do exist but cost more. And many are scams because they don't have enough volume of activated carbon. Any filter with a little bit of carbon added is going to be useless after a few days, or maybe even hours. The only VOC filters that work have multiple pounds of carbon, with the good filters having upwards of…

I was referring to the gases from the cars on the highway more than easily removed indoor sources.

The pollution from highways is primarily particulate matter: Rubber from tires wearing down, brake pad dust, particles disturbed by fast vehicles and kicked into the air.

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

#272

Post by Aurornis »

LegitShady wrote: post #172
energy123 wrote: post #61

Earlier quoted context omitted.

It's a good start, but for VOCs and gases you'll need activated carbon. Those 2-in-1 filters do exist but cost more. And many are scams because they don't have enough volume of activated carbon.

My common winix air purifier has a replaceable carbon filter.

Unless it has multiple pounds of carbon, it’s not doing much. These are for show.

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

#273

Post by throwway120385 »

mrob wrote: post #114
Aurornis wrote: post #60

Earlier quoted context omitted.

Living very close to busy highways is known to generate poor air quality. I recommend anyone in those locations buy an air purifier for their kids' rooms. I bought a couple reasonably priced HEPA purifiers and I change the filters on schedule. Replacement HEPA filters are very cheap. Also watch out for things that we do indoors that can generate bad air quality. I had a friend who bought a VOC meter and noticed very…

HEPA filters are counterproductive in standard air purifiers. Air purifiers pump their cleaned air directly into the dirty air of the room. It doesn't matter if that cleaned air is extremely clean, because it's immediately mixed with dirty air. What actually matters is how much clean air you produce: the "clean air delivery rate" (CADR). The more effective the filter the more it restricts airflow. If a filter is only…

I can buy a HEPA filter machine off the shelf. What I can't buy off the shelf is any other non-HEPA filter machine like you're describing. So while you might be right, there's no products readily available that meet the spec you're providing. We've got to work with what we have available and what time we're able to make for this stuff.

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

#274

Post by throwway120385 »

Retric wrote: post #74
Sha1rholder wrote: post #65

Earlier quoted context omitted.

Why would they cut corners? Activated carbon isn’t expensive.

Because it’s not obvious to most customers that a corner’s been cut. Same reason most new construction in the US sucks. You can safely put a washer and dryer on the upper floor of a house if you add a proper floor drain, but you’re unlikely to see anyone add a floor drain in new construction because buyers aren’t looking for it. Now multiply that by everything a buyer isn’t looking for and you’re talking real money.

What brand of washer do you use so I can studiously avoid it?

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

#275

Post by Aurornis »

throwway120385 wrote: post #273
mrob wrote: post #114

Earlier quoted context omitted.

HEPA filters are counterproductive in standard air purifiers. Air purifiers pump their cleaned air directly into the dirty air of the room. It doesn't matter if that cleaned air is extremely clean, because it's immediately mixed with dirty air. What actually matters is how much clean air you produce: the "clean air delivery rate" (CADR). The more effective the filter the more it restricts airflow. If a filter is only…

I can buy a HEPA filter machine off the shelf. What I can't buy off the shelf is any other non-HEPA filter machine like you're describing. So while you might be right, there's no products readily available that meet the spec you're providing. We've got to work with what we have available and what time we're able to make for this stuff.

> What I can't buy off the shelf is any other non-HEPA filter machine like you're describing

In locations with central air handlers, the filter in that handler already serves this purpose. That’s how my house is set up: Central handler has a high throughout MERV filter. Several rooms have additional HEPA purifiers.

The parent comment also has a fallacious argument in assuming that the CADR is too low if a HEPA filter is present, but even the cheap HEPA purifiers I bought have sufficient CADR to cycle the room over and over.

If you’re in a location with no central air handler (only mini splits or no air conditioning at all) and you have a giant space to cover and you have a constant exchange of air from the outside to overwhelm your filtration (must leave windows open, for example) then what the commenter above would apply. You would be better with a higher throughput, lower rated filter.

For everyone else, it’s kind of a misplaced “well actually” take that has just enough information to feel truthy but misses the bigger facts.

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

#276

Post by throwway120385 »

Gigachad wrote: post #152
enquirewithin wrote: post #143

Earlier quoted context omitted.

I’ve often wondered about this. Does the area immediately above where the gas stove was have an exhaust fan that vents to atmosphere? I would have assumed a properly specced exhaust fan would capture and remove combustion products from a gas stove?

I’ve never once been in a property that had an exhaust fan sufficient. I’ve had the exhaust on full blast and the spike on the air quality sensor on another floor of the house is rapid and massive. I suspect a sufficient ventilation would require something more like a lab fume hood that can pull a negative pressure on the area around the stove. And from what I have seen, a good number of exhaust fans are straight up…

There's a filter in it you're supposed to change regularly when they're in that configuration.

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

#277

Post by thfuran »

thelastgallon wrote: post #261
thelastgallon wrote: post #212

China has 350 million electric two-wheelers, 20 million EVs. China reduced air pollution from transportation by 80% in a decade. Delhi: 442. Lahore: 334. Beijing: 16. These are the levels of PM 2.5, one of the principle measures for air pollution, on November 19. How China cleaned up its air pollution – and what that meant for the climate: https://theconversation.com/how-china-cleaned-up-its-air-pol...

Outdoor pollution ---> Use these for transportation: walk, bicycle, e-scooters, public transit, electric 2 wheeler, EV Indoor pollution ---> Use these for cooking (induction, electric resistance) stove, heatpump waterheater and furnace for HVAC Would also be nice to do: stop using coal, gas power plants. These are usually farther out from cities and probably not the most urgent. (except when Elon Musk or new DCs deci…

>Delhi’s air pollution equivalent to smoking 50 cigarettes

Per day, which for some reason the headline didn’t include. Two packs a day is a pretty terrible baseline. At least it’s not addictive.

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

#278

Post by Hugsbox »

mboto wrote: post #251
Symbiote wrote: post #89

Earlier quoted context omitted.

The right (Conservative) and far right (Reform) parties both say they will abolish low-emission zones and other measures to reduce pointing traffic. They made it into a culture war topic.

Reform is not a far right party. It is important not to polarise.

Reform is a textbook far-right party, I'm not even sure why you'd try to argue otherwise.

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

#279

Post by kakacik »

vincnetas wrote: post #220
Aurornis wrote: post #60

Earlier quoted context omitted.

Living very close to busy highways is known to generate poor air quality. I recommend anyone in those locations buy an air purifier for their kids' rooms. I bought a couple reasonably priced HEPA purifiers and I change the filters on schedule. Replacement HEPA filters are very cheap. Also watch out for things that we do indoors that can generate bad air quality. I had a friend who bought a VOC meter and noticed very…

what a nice externality example "I recommend anyone in those locations buy an air purifier for their kids' rooms" I drive the car, you buy the purifier.

I drive the car, you buy/rent cheap place because its shitty polluted noisy place, so compensate that with air purifier. There is no free lunch in healthy society, there are good reasons for rent for same amount of m2 do wildly differ across same city and its not just sunset views or distance to work

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

#280

Post by red-iron-pine »

adrianN wrote: post #132
mrob wrote: post #114

Earlier quoted context omitted.

HEPA filters are counterproductive in standard air purifiers. Air purifiers pump their cleaned air directly into the dirty air of the room. It doesn't matter if that cleaned air is extremely clean, because it's immediately mixed with dirty air. What actually matters is how much clean air you produce: the "clean air delivery rate" (CADR). The more effective the filter the more it restricts airflow. If a filter is only…

Any air purifier should be able to cycle the air in a normal room often enough that it should be quite clean in a short time.

aye, like as long as you're not leaving the kids window open all night, or multiple other windows open nearby, it oughta fix itself soon enough
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