[coda_]

That's impressive... What are you using for purifiers?

[nerdbaggy]

I use the Alen Air 75i and have no issues getting my PM2.5 to 0

https://alen.com/products/alen-breathesmart-75i-air-purifier...

[bradknowles]

The best air filters I have found are the IQAir HyperHEPA filters, which are rated to filter ≥ 99% at 0.003 microns, which is smaller than a virus particle. That's why these are commonly used in hospitals. See: https://www.iqair.com/us/air-purifiers

[virtuallynathan]

That one seems a bit pricey, I think the best I’ve seen for CADR per dollar is the Conway 400(S) or Medify MA-112.

[ahaucnx]

The positive pressure system is from a local supplier in Thailand and only available in Thailand and China. PM me if you need more information.

[atombeef]

I'm curious about what supplier and system you're using? I'm currently using a bunch of smartair purifier, that gets indoor pm2.5 to close to zero even when it gets really bad outside every year (also in Thailand). But considering installing a positive pressure (ducted) system with HEPA filter due to high co2 levels (tightly sealed house and no ventilation)

[bmitc]

I am using Vornado air purifiers, but I don't have air quality monitoring yet and don't care about WiFi features. The higher end Vornados have monitoring built-in, but it is rudimentary and just a light bar. Without air monitors to check them, it's hard to tell, but they seem to work quite well. Vornado excels at producing room-sized torrents that direct air through its filters. We blew out a candle once and the smoke visibly made a beeline towards the Vornado.