How Dirty Is Your Air? | Hacker News Reader

How Dirty Is Your Air?

technologyreview.com

66 pointschewymouse53 comments

> The World Health Organization estimates that 80 percent of people living in urban environments are being exposed to unhealthy levels of air pollution from particulates and it says they cause four million deaths annually around the world.

The level of particulates middle-class people face indoors in the worst urban environments is tiny compared to the level of particulates people face (esp. in rural areas) wherever cooking is done indoors over a wood fire. We’re talking about a level of wood smoke filling the room which causes eyes to redden and start watering, and makes it physically difficult to breathe. (Source: my parents are anthropologists and my godparents are indigenous rural Mexican peasant farmers, and I spent lots of time growing up sitting next to wood-burning hearth fires.) On average, by historical standards, humans’ current exposure to particulates is very low and continues to drop every year.

I don’t know if it makes sense for people to freak out about cooking eggs in their houses, though having effective indoor ventilation is obviously worthwhile, all else equal.

Edit: I looked up the actual WHO source (not linked in the OP): http://www.who.int/mediacentre/news/releases/2014/air-pollut...

> After analysing the risk factors and taking into account revisions in methodology, WHO estimates indoor air pollution was linked to 4.3 million deaths in 2012 in households cooking over coal, wood and biomass stoves.

This is not talking about people using a gas range with an underpowered ventilation hood to cook eggs, and the 4 million deaths number is not restricted to urban areas. The people dying here don’t need a little electronic air quality detector, they need electrification and rising incomes so they can afford better heaters and stoves.

To cut outdoor air pollution, we should get people to stop burning piles of trash, stop using fire to clear large areas for agriculture, switch away from coal power plants as soon as possible, and try to get the worst polluting old vehicles off the roads.

Agree with all of that.

Still no reason not to be optimizing our environments a bit more than the usual person might. There are less obvious threats to respiratory health in the developed world but the ones that are left are probably more insidious e.g. radon gas, VOCs from paints.

Having cooking fires sucks for the women tending them in the Third World but most family members probably aren't in the house/hut for most of the day. They're probably engaged in plenty of physical activity outdoors. We on the other hand are sitting in places with artificial florescent lights and are in the same spots on a consistent basis.

We should:

- have natural sunlight (using my magical heliostats)

- run about more

- be surrounded by plants (perhaps visits from cool animals)

I should start a minor religion.

I live in China and have a Laser Egg (1) in my home. It's extremely accurate, often matching the AQI reading found by online services. What I'm interested in is learning how to purify the air inside. I knew cooking was a major culprit in raising PM2.5 levels. But even when running two air purifiers sometimes the AQI just can't be lowered too much. I think it's leaky seals in the apartment. We're on the 18th floor and on a windy day can feel a huge draft from the front door and hear the wind escaping the balcony windows.

1. http://www.originstech.com/products/laseregg/

I bought a top rated air purifier a couple months ago off of the recommendation from Wirecutter. I live in SF, not China, but it's dramatically improved quality of life in my apartment. It cleans out smokey air from cooking very quickly, and cuts down dust/particulates especially in the spring months when pollen is everywhere. Highly recommend.

Just curious, which purifier?

Probably Coway AP-1512HH Mighty.

http://thewirecutter.com/?s=air+purifier redirects to http://thesweethome.com/reviews/best-air-purifier/

Yes, the Coway. I've had it for a few months now and just leave it on all the time on auto/eco mode.

If you haven't seen it, this TED talk on using plants for air purification is pretty cool: https://www.ted.com/talks/kamal_meattle_on_how_to_grow_your_...

One thing I've never figured out about air purification is how to keep air both particle-free, and oxygenated. I don't want to seal all my doors and windows to run an air purifier—I immediately feel suffocated by the CO2 buildup from my own breathing. Is there a best of both worlds?

More plants in your house. It makes a surprising difference.

Fresh air systems are what you are looking for. They purify and bring in outside air (be warned, they lower HVAC efficiency), a lot of them with a high enough CFM to pressurize your house to, exhausting all of the air inside outward so that the leaky seals aren't an issue.

The problem is that these don't fit into most Chinese apartment rentals. Landlords could make some big bank by installing an HVAC, but they are missing even in new buildings where 90sqm apartments are going for more than a million bucks.

Yep. My little apartment (400m²) in a low-rise in Canada, built just five years ago, has no in-unit ventilation whatsoever. If I want a cross-breeze (and I always want a cross-breeze), I have to open the outside windows and the door to the hallway, and let a ton of dust and pollen flow into the unit from outside. I have no idea who thought building an apartment building today like this made sense, but it seems to be a common perspective.

400 sqm is a "little" apartment? Sheesh, first-world problems :)

I open the windows for 20 mins, twice per day. The rest of the time, the windows are closed and air purifiers are on.

Modern insulated houses (think Passive houses) have automatic heat recovering ventilation because everything is sealed. Many heat recovering ventilation systems that have an air purifier integrated. Many also vary ventilation automatically depending on the inside air quality.

That's why HRV systems exist.

Keep your environment's air clean while retaining the heat plus circulating fresh oxygen.

I intend to get a decentralized HRV like Lunos for my passive Tiny House. Any problem regular houses have with air quality, will be multiplied in a Tiny House without proper precaution.

You need good Windows. We switched our apartments in Beijing, and it made a world of difference in indoor air quality with our big blue air running. The problem that "purified air" becomes stagnant enough to be uncomfortable, even if clean, so we open the windows whenever the AQI is below 170 as long as a dust storm isn't going on.

I have purifier with large HEPA filter, purifier with water filter, ultrasound humidifier, but the best result so far is by vacuum cleaner with water filter (Thomas with Auquafilter). Water works extremely well against tiny particles, much better than HEPA.

I'm curious about the composition of the particles emitted when frying the eggs, and on the specific toxicity of cooking oil droplets and specs of albumin...

I'd expect both to be readily processed by macrophages, without harm, unlike the soot particles produced by burning either wood, coal or petrol derivatives...

Makes me wonder how much it would cost to turn an oven range hood into a full-on chemical fume-hood, with the hanging plastic isolation flaps.

Funnily enough I'm just embarking on a little project to monitor the the air around me and have ordered a particle counter off ebay (http://www.ebay.co.uk/itm/New-Hot-Selling-USB-Port-Laser-Dus...)

£29, hooks up to usb somehow. I've yet to get it and try to figure drivers.

I'm now trying to find a cheap NO2 sensor. Those seem to be the main categories that do people in in London. The Guardian figured 3,537 deaths for pm2.5, 5,879 deaths from NO2 in 2010 approx.

https://www.cooking-hacks.com/no2-gas-sensor-5339

Update - bought and cancelled that one as it's specs didn't seem sensitive enough - not quite sure - says to 0.05ppm which is still quite high. Now checking out http://www.alphasense.com/index.php/products/nitrogen-dioxid...

Is this an ad?

It certainly reads like one.

Yes, and these cheap devices sadly don't have accuracy description. I would be OK to pay for it if some accuracy would be guaranteed, but writing that it's calibrated and not specifying the maximal error looks always fishy.

I would also be wary of how the accuracy declines over time. E.g. how does the device keep properly sized dust from staying or small scratches from developing on the surfaces that are involved in the measurement (e.g. lenses and mirrors for optical devices)?

Especially when there are very similar [1] devices selling in China for about 1/3 the price (where bad air quality is more than what you cooked for breakfast).

1: http://www.originstech.com/

During undergrad, me and some peers (all chemists) talked about having such a network of air sensors. Having good resolution on air quality measurements could drastically improve the quality of life of people living in big cities. We never knew how to monetize this, however. One way we thought about was to install a private network of sensors (inside and outside houses) and then sell the datasets to research agencies. Doesn't see too profitable though.

Ideally what you need is a machine that can take different measurements: wind speed and direction, temperature, humidity, VOC levels, ozone, nitrogen compounds and general particulate matter.

A static network of sensors is a great start, but your measurements basically define a surface. What you'd want is a fleet of drones which could "stand still" in formation, let's say a 50 x 50 x 50 drone cube each 1m apart, and take volumetric + time measurements. That would be _awesome_ :)

There's a fair network in London https://www.londonair.org.uk/london/asp/PublicEpisodes.asp

The pollution seems fairly spread out so I'm not sure how much having higher resolution would help. I think those are government/council owned.

I was toying with a commercial service where householders could pay a bit for measurements on their homes and could try to counter bad stuff with filters and the like. Not quite sure about the economics - the cost of sensors seems to be dropping rapidly. The government monitoring stations I think are like $25k but there's cheaper stuff out there.

I think I've seen projects that put sensors on delivery vehicles... not a nice group formation, but at least it linearly covers a lot of areas at different times of day.

Reasonable lower priced option from china:

https://www.amazon.com/UNI-T-UT938C-Detector-Thermometer-Tem...

or slightly lower priced slightly older version on eBay

http://www.ebay.com/itm/UNI-T-UT-338C-Indoor-VOC-PM2-5-Air-Q...

Some indoor air purifiers have particle count sensors that activate the purifier fan.

BTW - anyone have recommendations for an air purifier with a true HEPA filter?

I've heard good things about this: http://smartairfilters.com/en which is really just a fan with a HEPA filter attached to it.

Was looking them earlier - really like what they're doing (back to basics - airflow + HEPA Filter) but prohibitive shipping costs to UK/Europe from China

I was looking at this a few days ago http://www.philips.co.uk/c-p/AC3256_30/3000-series-air-clean...

It has good reviews on Amazon, but it's not cheap.

You can make your own:

<https://www.youtube.com/watch?v=kH5APw_SLUU>

I have both the HEPA air purifier and energy recovery ventilator from these guys: http://purifresh.com They work pretty well (keep my wife's allergies in check) and are simple but well-constructed units.

Edit: but they are US based so shipping may be equally expensive to the UK.

Unfortunately all the ones I've seen give wildly inaccurate readings.

Living in China I've measured particle count way too many times with different sensors. :)

Canary - https://canary.is/ - the home security camera comes equipped with sensors that are capable of measuring air quality. I reckon this will be a big deal for a lot of people, although right now most don't even know that such measurements are possible or why they're important.

Surprisingly, I haven't heard of AirViz before. Their CEO is Allah Nourbakhsh, CMU Robotics Institute professor, previously(?) involved with GigaPan.

not a very good name for international expansion as "Speck" means "bacon" in German.

https://de.m.wikipedia.org/wiki/Speck

Are there anywhere near enough German speakers to make that a problem?

roughly 100 million, which is not that much in the cosmic scale of things. But if it becomes a globally successful product, they'd have to live with sarcastic comments from us, or come up with a different name in DE.

Sounds like a great name, who wouldn't want to buy the Bacon 2.0 machine? :-)

I dunno, if you are fretting over particulates from cooking breakfast, a bacon meter sounds like a fine way to keep track of it.

This is a clickbait ad, "See what one family learned!" I come to HN to avoid this.

  MIT Technology Review Magazine

Better than your average clickbait, but yeah cliffhanger-as-headline is a cheesey tactic.

I still enjoy this site, as a serious indicator of regional, population-center-oriented indicator of air quality: https://plumelabs.com

I wish that I could just come to the full-throated defense of MIT's publications, but I think we all know how press offices can be, and that doesn't reflect on the researchers or academics IMO.

If you've ever worked as a cleaner you'll appreciate what tobacco smoke, foods cooked in Indian style, people not venting their rooms (hello mold) can do to the furnishings, walls and ceilings. Maybe if your environment is turning a deep ocher, it isn't healthy to live in it. I am completely unsurprised if the people who live in them die younger.

People with wealth probably imagine themselves immune to the problem as they have a cleaning staff but that is not true either. They need to watch out with new cars and new houses. These should be ideally left alone for up to six months so the off gassing of paints, lacquers, chaulking can happen and also the dust level from construction can die down.

Yes it's an advert but the problem itself is a real one.

Dirty air will grind your respiratory system down. Your lungs. You need those to breathe.

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