So I have a bunch of home automation projects I’ve been tinkering with weather related. One of which is an air quality sensor that determines when the air quality is bad with the intention of displaying some visual notifications around the house. I’ve been working on the coding for it and currently have it sitting on my desk in my home office. My most recent addition to it was having it graphing the data out to a webpage on my home network so I could see the change over time. The day I finished it and started testing was the day before Thanksgiving, my niece, 14 years old, decided she wanted to spend the night to hang out with her cousin, my son, since her mom and dad were coming over for Thanksgiving the next day anyways.

My home office is also our guest room, so the bed she sleeps in is in there. She went to bed about 10, I went downstairs to play some video games and have a couple of beers. I finally went to bed about 1 am, when I walked passed her room, I could hear her talking on the phone.

Next morning comes and after everyone is up and moving I decided to check on my air quality sensor and see how the data looked on the graph. As soon as I pulled up, something was really suspicious. It was basically a flat line with values between 1 and 5 most of the time, but at 1:05 am and 1:15 am it spiked twice to ~150. I took me a few seconds to put 1 and 1 together… “the only time I’ve ever seen it get that high was when food was cooking and there was smoke coming off the stove”… ohhhhhhhhhh.

I called her into the room and showed her the paper and told her, “The only reason these numbers would show like this is there was some kind of smoke in the room”. She said, “I don’t smoke”. I said, “Or something like a vape pen.” Her face went white, “Are you going to tell my mom?” “No, but you need to give me the vape pen”. So now I have a vape pen.

  • hackcasual@alien.topB
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    1 year ago

    Air quality sensors are scary, especially if you’ve got a good CO2 sensor. I can tell when my partner is home, food is cooked, window open, small group visiting, large group visiting, far-uvc sterilizers running, all from a few numbers from

    • fallguy25@alien.topB
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      1 year ago

      I bought a Kidde Co2 monitor the other day which also monitors TVOC. It’s fun to watch it get mad when there is a whole lot of cooking going on (ie Thanksgiving)

    • -Avacyn@alien.topB
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      1 year ago

      I’ve been looking into room presence detection for a while now but regular motion and mm wave just fall short… honestly, using CO2 monitors might actually be a valid alternative. Something for to look into. Thanks for the inspiration.

      • WilliamAndre@alien.topB
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        1 year ago

        My university did some research on non invasive attendance counting by using CO2 sensors. They were able to tell relatively precisely how many people were in a room by using only those.

    • reddysteady@alien.topB
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      1 year ago

      I’d love to know how you can tell these things and also if you have any automations etc set up to use the results?

    • ThinkSharp@alien.topB
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      1 year ago

      Just got mine. Only set it up Thursday.PM2.5 has been insistently high. Any ideas what causes that? Only asking you because you seem familiar with that sensor and the data signals / corresponding drivers

    • matunos@alien.topB
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      1 year ago

      Honestly though, there are easier ways to know if a small or large group is visiting your house.