A few years ago I used an RTL-SDR to determine if I had a water leak since my meter is one that broadcasts over 900mhz (iirc). I wrote a small program to parse RTL-AMR output into Prometheus metrics (real life gauges are just like Prometheus gauges, who would've thought) and tracked it over a week while I was away on vacation. No leak luckily.
We do this regularly in production. We do biweekly container rebuilds, many running alpine and installing version unpinned packages. So far very few (if any) actual issues with that. We do of course do smoketests prior to promoting to production.
I've seen these studies before and done some testing of my own and found this to be true to some degree. I've used PMSA003I and BME688 sensors to check for particulate and VOC's. I didn't notice any significant increase in PM1 or PM2.5 (which is probably to be expected since the particles emitted are probably <1um and lower than I can detect). I did see some increase in VOC's but nothing alarmingly high from baseline. Roughly equivalent to lighting a candle.
It's important to note that particulate matter and VOCs are not equal in danger and bodily effect. For some reason people act like they are all the same. It's like saying you got liquid in your eyes: the type of liquid matters an awful lot.
In a lot of cases, the VOCs emitted when you melt plastics have "unknown" long term effects because nobody has been exposed to it in great levels for extended periods. We know some are potentially carcinogenic, but that's about it. This isn't true of candles, though. We have a pretty good idea of what candles can do to you.
Another more concerning part of 3D printing though is UFPs, which generally can't be filtered out easily by consumer grade air filters, and due to their tiny size can enter deeper nodules in the lungs. Reminds me of asbestos.
I'm no expert in any of this, but you should be worried about 3D printing fumes. The 3D printing community is going to become a long term study of the effects of microplastics imho.
There does seem to have been a slight shift in mentality over the last couple of years in the 3d printing community, with groups of users obsessing over statistics from air quality and particle sensors.
One thing that is a bit concerning is people building their own air filters and releasing them to the public as a 'solution' to 3d printer filtration, with the creator having no real experience or knowledge in the area other than looking at their cheap air quality sensor and seeing a difference.
As comfortable as 3M half-face respirators are, having people in the room wear a mask until vapors subside is a hassle - especially if the room is in the basement or a northern climate where opening a window isn't possible or desirable.
> This isn't true of candles, though. We have a pretty good idea of what candles can do to you.
For beeswax and simple paraffin. I'm not so sure this is what candles are made from these days. I've ordered some raw paraffin from Amazon, and it smelled like a chemical plant*. I've had a few candles from big box stores that smelled similar. I stopped using candles, because it appears their ingredients have strayed.
* Reviews can be found for "beeswax" saying the same.
> I've used PMSA003I and BME688 sensors to check for particulate and VOC's.
Keep in mind that the VOC sensors you're talking about aren't designed to pick up all types of VOCs. They're designed to detect specific types of VOCs (eg. ethanol or acetone) associated with human occupation and/or urban pollution[1], because that's the use case that they're designed for. If you use them to measure something entirely different (eg. plastic fumes), it shouldn't be surprising at all that they don't pick up anything.
That gives you an estimate of the quantity of VOCs, but tells you nothing of their toxicity. You can have a VOC that's extremely toxic at low concentrations, and a VOC sensor would read barely above baseline.
Iirc grafana ~v8 had the ability to send pictures of graphs with alerts natively which was pretty nice, seems like v9 doesn't have that built in anymore.
Yes correct, also Grafana v9 has it, but this is a different situation, I don't want an alert with the graph, I want a daily report with the full dashboard, even if no alert is triggered.
Anyway I wrote also a post about my Grafana alerts, that are delivered to my as Pushover push notifications: https://giuliomagnifico.blog/tips/2022/12/12/Grafana-Pushove... (without the images, but with the panel ID/URL, so you have only to tap if you want to see the full graph)
I mean that could satisfy the interviewer, but for me if I asked that question, I'd want an answer that protected against overflow and unfortunately the naive solution is prone to overflow.
I've had great success using home assistant's built in energy monitor dashboard and a ESP32 based power monitor from CircuitSetup. Home assistant supports exporting metrics via Prometheus which I then graph using grafana for fancier dashboarding.
As someone who did IT at a public transit agency for a medium sized city briefly, this is all pretty accurate and similar at most public transit agencies. Even brand new busses are still using old hardware under the hood that requires special deutsch to serial cables that require windows 7 machines to interface.
Likewise all the software that runs transit agencies is extremely dated and heavy.
RTL-AMR: https://github.com/bemasher/rtlamr