Let's Monitor Our Air Quality

Inspired by Armidale council installing https://www.armidaleregional.nsw.gov.au/news/news-2018/live-… relatively inexpensive but reasonably accurate air quay sensors the public can see real time (not 24h average) readings of It quality.

If you think this is a good idea here is what you can do to help:

Comments

  • +1

    relatively inexpensive

    INEXPESIVE??? It starts from $179.00???

    • Reference monitors that the EPA uses cost $20,000.

      PurpleAir has been tested by a third party and shown to be reasonable accurate https://www.wunderground.com/cat6/purple-airs-250-air-pollut…

      • +1

        They are cheaper at eBay ($38.69).

        • +1

          Buy the sensor and make your own: https://www.ebay.com.au/itm/232389616832.

          All these cheap meters use the same sensor.

          They work by counting particles that pass thru a beam of light, and so are all that accurate for all conditions (humidity, particle type) but good enough for "well, it's better than yesterday" stuff. You can calibrate them for what you are trying to measure and for local conditions, but who does that.

          • +1

            @D C: …and that should be …"aren't all that accurate" of course.

            That is don't trust the actual number, but how it changes. Lots of woodworkers use these to check on how much crap is in the air when sanding, painting and so on.

    • Think that's in USD so you'd probably get one with $20,000 AUD

  • Is this an advertisement for PurpleAir?

    • I bought two, I'm not associated with the company or receive anything for posting this. My motivation is to monitor NSW in more depth. I've been worried about air quality and my health since the smoke filled day in Sydney this week.

      • -2

        Nice try

      • +1

        My motivation is to monitor NSW in more depth.

        Monitor the air quality and then what? It’s not like you can do anything to change it.

  • real time (not 24h average)

    From the NSW Air Quality Index site, use the visibility index as a lead indicator of PM2.5 levels, etc. You can also download/view the hourly data from the website for your location.

    • Wouldn't the pm 2.5 column be a better indicator than the visibility column, of pm 2.5 particle levels? Am I missing something? Haha

      For OP, looks like Armidale already has a counter as per ihbh's comment

      https://www.dpie.nsw.gov.au/air-quality/current-air-quality

      The visibility column for Armidale is missing, but just refer to the other two columns. You can see visibility during the day at least lol, so that data isn't that useful.

      • The PM2.5 column is a rolling 24 hour measure (that is, 24 hour moving average). It can show high while visibility is low because it, say, includes poor measures from yesterday. But the hourly one is fine like the visibility. You could end up being stuck in your house for no reason. Likewise, it will take longer to register a high measure, when you should start going in side when the visibility measure deteriorates.

        If you're not sure, download the hourly data for both measures and compare to the PM2.5 measure (rolling 24 hour) and see what I mean.

        • Oh yeah, I forgot about the rolling 24 hours thing. Wish they'd test every hour. But if you check hourly and it's been bad then suddenly jumps down to yellow, you know there's been a pretty drastic change in quality :). Since it's just an hour out of 24 that has brought the average down.

          I didn't rely on the visibility thing because of water (humidity), smog (car pollution etc) and dust particles also factoring into visibility. In Singapore for example there can be days where it's high humidity and low pollution and low pollution and high humidity- both can have exactly the same visibility reading.

          Not sure about Australia where it's dry, how much water would factor into visibility. Might be a better indicator since 24hrs is such a long time.

          • @Bargainbeth:

            But if you check hourly and it's been bad then suddenly jumps down to yellow, you know there's been a pretty drastic change in quality :).

            Unfortunately it doesn't happen that way 1. because only 1/24 of the affect is taken into account which reduces the impact. 2. Even if it did, it's useless and could be counterproductive. You've been stuck in your house for a day and not airing while the conditions are okay outside. And then when you go out, or air the house, the reverse occurs - conditions deteriorate, but the 1/24 impact doesn't show its significance until later.

            • @ihbh: I know what you mean. But mathematically if you keep an eye on it each hour and it's stable for 24hrs then suddenly you see a bit of a hike, you can use maths to work out what the air quality is now.

              For example, where I live, the air quality has been at 100-106 for pm 2.5 pretty much every hour I've checked. (barring sleeping hours). I'll assume its the same as when I woke up it was the same.

              Just this hour it went up to 132. So for it to hike up by ~27 in the past hour means that the air is significantly bad right now.

              I'm going to try and math this, not even sure if it's correct. Feel free to criticise.

              X is current air quality

              So that's 132 = [(~105)(23) + X]/24

              3168 = [(~105)(23) + X]

              3168 = 2415 + X

              X = 753 (assuming air quality was the same when I slept or wasn't checking and updated hourly as a rolling 24hr average).

        • Where do you access hourly data for pm levels?

  • I prefer our council to spend our rates on road maintenance and rubbish removal.

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