There are many white labelled brands of these devices and so a variety of sources of replacement filters tend to appear.

This is an outdated list of sources simp.ly/publish/0P5fBm

Several small air purifiers may be a better solution than one large one. You might think that this would improve the homogeneity of filtration in a room. But we've also built large purifiers to carry out a few tests, like this model with a capacity of 450 m3/h.

It’s has a GB/T tested CADR at turbo speed of 600m3/hr at a reported 51.5dBA. The issue is that there is no mention on CADR and noise levels at the other 4 speeds which is what’s needed for it to be useful in the tool (unless noise isn’t an issue at 50dBA)

If you find any send it through and it will be added to the tool

From a single data point (e.g. high CO2), you can’t know the ventilation rate. The rate that the CO2 changes over time is required. That said, it can tell you something. For example, if the room is crowded and the CO2 is low, you can assume that the ventilation must be pretty good.

Pricing and availability of devices is a year or two out of date. There are some newer DIY options missing too. Anyone can message this account with new devices and specs to be added

Many manufacturers will inflate room sizes and CADR figures.

Before you buy an air purifier, always check the actual CADR figures and the recommended room size.

Visit the ENERGYSTAR database www.energystar.gov/productfinde...

Or check the @cleanairstars.com tool filters.cleanairstars.com

The total views on the channel is approaching 10k, which is pretty wild for a channel dedicated to explaining how aerosol affects human health.

You could also argue that a larger space/higher ceilings is somewhat protective as aerosols have more room to dilute into, but as mentioned they won’t necessarily dissipate as quickly as CO2.

But importantly, it takes longer for CO2 to reach its steady state in a large space. Someone could be in a poorly ventilated space for a while before CO2 reveals poor ventilation.

In a large space where someone is in close proximity to an emitter and there’s little active or passive mixing. CO2 will generally diffuse more evenly throughout a space than aerosols.