[HN Gopher] Low-cost open source device can measure air pollutio... ___________________________________________________________________ Low-cost open source device can measure air pollution anywhere Author : GavCo Score : 91 points Date : 2023-03-16 18:44 UTC (4 hours ago) (HTM) web link (news.mit.edu) (TXT) w3m dump (news.mit.edu) | l1am0 wrote: | This feels like old news. Built such a thing for a german hacker | initiative like 7years ago. Back then sub 50EUR and still runs. | | Data available at luftdaten.info | | https://sensor.community/de/sensors/airrohr/ | MandieD wrote: | We built those and got them running one evening at a Meetup in | Erlangen - looks like they had to switch to a | temperature/humidity sensor that requires soldering the pins | on, because the ones we used back then came ready to plug in, | not a soldering iron in sight. | uoaei wrote: | Official repo: | | https://github.com/MIT-Senseable-City-Lab/OSCS | mistrial9 wrote: | there is an old man in Berkeley who has made very good money for | more than thirty years, designing and selling these. No, he does | not want to "open source" it (I tried). | grozzle wrote: | It would be useful if headlines said "~$10", "sub $100", "sub | $1000" et cetera, instead of vague terms like "low-cost". | cinntaile wrote: | According to the linked paper in the article it's <2500usd. | | https://doi.org/10.1016/j.atmosenv.2023.119692 | cwkoss wrote: | I wouldn't call that 'low cost' | Karawebnetwork wrote: | Link to project website: https://senseable.mit.edu/flatburn/ | | Link to assembly guide: https://github.com/MIT-Senseable-City- | Lab/OSCS/blob/main/Bui... | | Link to bill of materials: | https://docs.google.com/spreadsheets/d/1-fR-0hTxHKbjaRf8DbH6... | | Naively searching for every lines of the bill of materials gives | me around $300, with a handful of items being around $50 and | everything else under $5. I'm sure a hobbyist could find the | parts for cheaper, especially things like individuals connectors | that I found for around $5. I've seen them go as low as $0.25 | when bulk purchased. | | Disclaimer: it's possible that some SKUs led me to the wrong | products. I am not into electronics. I encourage you do to the | same exercise before drawing conclusions. | clnq wrote: | Not to undermine the DIY aspect which could be fun, but it | looks like you could buy an Atmotube for about half as much (if | you take the research survey) -- https://ukstore.atmotube.com/. | Though it doesn't register noise levels. | | They can also build you an Atmocube which can measure noise and | a few other things for $200-$500 based on what I found online. | theaussiestew wrote: | Impressive, I've been wanting to build a portable version of this | for a while now. It would look like a smart band but integrate | environmental sensors and the users would then be aware of how | their environment is affecting them. They would also have the | option of contributing their data to a collective dataset. | dariosalvi78 wrote: | I had a similar DIY project, also using some Alphasense sensors, | + some cheaper metaloxide ones. It was somewhat promising, but it | needs long-lasting colocation studies and, after I moved to | Sweden, I lost any support from the local authorities and gave | up. https://bochovj.wordpress.com/tag/air-quality/ | Rebelgecko wrote: | How does this compare to something like an Airgradient, which you | can put together for like $50? More detail about what constitutes | the PM2.5 or PMn particles you're measuring? | gnramires wrote: | Can't find the air quality sensor on their bill of materials | shrx wrote: | The Readme file [1] on their GitHub repo contains this bill of | materials: | https://docs.google.com/spreadsheets/d/1-fR-0hTxHKbjaRf8DbH6... | | This lists a "particle module", a temperature sensor and some | other seemingly irrelevant sensors (GPS, accelerometer). | | [1] https://github.com/MIT-Senseable-City- | Lab/OSCS/tree/main/Bui... | | edit: looks like the "particle module" is just a LTE/BT | communication module, so really there don't seem to be any | environmental sensors other than for temperature. | detaro wrote: | You are only looking at the list for the main board, the air | quality sensor carrier is the second sheet of the doc. | adolph wrote: | It only includes a particulate matter sensor and "Analogue | Front End (AFE) Alphasense A4 Air Quality Gas Sensors" but | not the sensors to use. | gnramires wrote: | Thanks! | ivarvong wrote: | There's a mention of the SEN5X here: https://github.com/MIT- | Senseable-City-Lab/OSCS/blob/main/Bui... | antoniuschan99 wrote: | I also see an alphasense afe, and bme280 | e44858 wrote: | The particulate sensor is Sensirion SPS30, mentioned on the AQ | Ext Board tab in the spreadsheet. | gniv wrote: | The key word -- which is missing from the PR title, but is in the | paper title -- is "calibration". The novelty is there. Apparently | this is a big problem due to varying humidity levels. | Havoc wrote: | Not just humidity - CO2 equivalent sensors are also quite fond | of drifting | AceJohnny2 wrote: | Usual disclaimer that MIT's PR dept is really effective (I've | stopped paying attention them because of so much hype), and | there's quite a chasm between a proof of concept and a mass- | market device. | alsodumb wrote: | Yup, they are really good. | | The Open Agriculture fraud is a living example: | https://gizmodo.com/mit-built-a-theranos-for-plants-18379682... | gumby wrote: | That one was supercharged by the Media Lab's PR organ. But | even without that assistance, the regular MIT "news" office | is head and shoulders above its peers in making the trivial | appear transformational and the outstanding appear...boring. | | My favorite was a publicity piece about a new proof for the | behavior of higher-order manifolds with some absurd | justification as to why you should care, something like how | it would revolutionize battery electrodes or something like | that. | | PS: "living example" was a nice touch. | alsodumb wrote: | Hahaha I was worried no one's gonna get my pun. | jl6 wrote: | I don't know if this is the device to do it, but the premise is | solid: create awareness that air pollution is a real thing | affecting specific areas in which _you_ are breathing right now, | not just an abstract bad thing that may or may not be happening | somewhere to someone. | cactusplant7374 wrote: | I'm debating buying one for myself so I can judge whether air | pollution is effecting my asthma. You can find AQI for a lot of | cities but it appears the calculation often isn't done with | local devices. Satellite imaging? | photochemsyn wrote: | This sounds highly implausible for anything other than very crude | and not-very-useful measurements. Quantifying air pollution is a | fairly hard problem, chemically speaking. The composition of | particulate matter is highly diverse as it may arise from a wide | variety of sources, i.e. agricultural, industrial, wildfires, | diesel engines, etc. Just looking at the particulate PM2.5/PM10, | broadly speaking there's the organic carbon fraction and the | inorganic metal fraction. The former is highly complex, e.g.: | | > "The considerably increased chromatographic resolution in GCxGC | [gas chromatography] allows separation of many UCM [organic | carbon] compounds while the TOFMS [mass spectrometer] supplies | mass spectral data of all separated compounds. However, the data | sets are getting enormously complex. In a typical PM2.5 sample | from Augsburg _more than 15,000 peaks can be detected_... " | | https://www.sciencedirect.com/science/article/abs/pii/S00219... | | Some particulate matter may have a heavy metal fraction, some may | not and that's also not easy to determine (but was a major factor | in leaded gasoline pollution). Here's a sample of the kind of | work that has to be done to get reliable measurements: | | > "...using quadrupole inductively coupled plasma - mass | spectrometry (q-ICP-MS). We report improved measurements of key | aerosol elements including Al, V, Cr, Fe, Ni, Cu, and Zn in | airborne coarse particulate matter (PM10)... This technique was | used to determine the elemental composition of over 150 PM10 | samples collected from an industrialized region in Houston, TX." | | https://www.sciencedirect.com/science/article/abs/pii/S00032... | | On top of that there's nitrogen oxides and PAN, ozone, etc. The | only relatively inexpensive recent innovations seem to be the use | of drones to collect samples for lab analysis (would have been | useful in East Palestine). | | Getting accurate measurements of all the species involved in air | pollution requires a modern analytical lab packed with equipment | that costs hundreds of thousands of dollars and highly trained | technicians to operate. The press release and snippets from the | paper don't address such important details at all. | Severian wrote: | Not only that, but they are deployed on top of automobiles, | where the air quality in the surrounding air is going to be | worse to begin with. I understand the benefits of using GPS, | but I don't see where they mention this being an issue. | ddulaney wrote: | Most definitely it's hard to dig into the actual composition of | air pollution. But "how much PM2.5 is in the air", while | definitely crude, is still extremely useful. That said, decent | sensors for PM concentration are already pretty cheap (<$100 | for a module; ~$100 for a full package), so unless the price is | going way down it's unclear how useful this particular | innovation is. | ckocagil wrote: | A lot of these cheap, portable sensors "cheat" in one way or | another. E.g CO2 sensors that assume they'll be subject to open | air once every few days, using that minimal CO2 value as a | baseline. So while they give numbers which can be useful if the | user is aware of its limitations, they're far from being | analytical tools. | | In contrast PM is pretty easy to get right. Shine laser, count | particles. ___________________________________________________________________ (page generated 2023-03-16 23:00 UTC)