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Comment by akor | Hacker News Reader

I've wondered if air quality was an issue where I live but wanted to also be able to do something about it so I bought and air purifier with an air quality sensor (Winix D480). It mostly kicks up in the morning but I have no idea what is causing it to think the air quality is bad. For those who've gotten a real sensor how do you track what's actually causing the air quality issues so you can do something about it? I live close (1400ft / 444m) to a major highway so I've wondered if that could be a "source" but no idea how to tell.

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Do you happen to eat toast in the morning?

>“The scariest thing in this house is probably the toaster,” Erin Katz, another student volunteer, said. “I just had no idea that toasters emitted so many particles.”[1]

[1] https://www.newyorker.com/magazine/2019/04/08/the-hidden-air...

Yes, quite frequently. I haven't read it yet but had heard cooking can trip PM2.5 sensors up but I guess I assumed that air quality issues that come from something you eat would be less detrimental to health (as a general rule). It could certainly explain the propensity to kick up in the morning. Thank you.

I’ve got both - air purifier with a 2.5pm readout. Plus a separate sensor that does 2.5 and 10pm.

Things that trigger it - mainly cooking. Even normal cooking can shoot levels to 4x WHO recommended.

After that I’ve found that moisture can be picked up too. Ie shower. And finally on cold nights opening windows. Cause wood and gas heating by others

Do you happen to live in an apartment building? In my case, pollution from the downstairs neighbors would affect my apartment. Especially cigarette smoke, which my neighbor only smokes indoor in the morning.

Cooking breakfast is also a huge source of pollutants.

I live in a single family dwelling so it's probably breakfast then.

For my apartment, highest polluters include: dishwasher heating cycle, cooking, neighbor cigarette smoke, and air leaking in from main door. Adding weather stripping on the main door has substantially reduced the ambient pollution levels of my unit.

Adding stripping to my patio door that opens towards the main street helped me a lot. I am also surprised at how much noise isolation this added.

This makes my dwelling more air tight, so it's not good for carbon dioxide but I simply open windows outside traffic hours.

> It mostly kicks up in the morning but I have no idea what is causing it to think the air quality is bad.

If it's a standard PM sensor, those usually have a high temperature correlation that needs to be compensated for, and turning on the heat in the morning would likely produce a false positive with only naive signal processing.

I have laser PM sensors indoors and outdoors. Every morning my indoor one goes nuts. I have found that it's due to my SO spraying hair products.

Does it say what type of pollutant? PM2.5 is very different from SO2 which is different from O3, etc.

SO2 and O3 sensors are very expensive, so almost all sensors made for homes measure PM.

In that case it's almost certainly the highway. Tires are a massive source of PM2.5.

That's my main concern although maybe air pollution from toast / allergens is just as bad.

No it's just an LED that's either blue, orange, red. I knew it wouldn't give me exact figures (or pollutants) but from what I'd read the "fix" was to get an air purifier or move.

shower

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