Novita 101 is effective against PM2.5, it has a HEPA 11 filter.
Airvax too low airflow to be of any use. Too ex.
PS.
>>The next-generation filter from AIRVAX differs from existing filters
A HEPA filter and electric negative ion filter are used in existing air purifiers,
but the HEPA filter is not effective in collecting dust under 0.3 microns and the electric negative ion filter produces ozone, which causes vomiting, dizziness, atopy and respiratory organ disease.
The above statement in bold is wrong. HEPA has a 0.3 microns MPPS or Maximum Penetrating Particle Size. Below this 0.3 microns size, efficiency usually rises.
On taobao sites selling HEPA and ULPA/Ultra Low Particulate Air filters that are of Cleanroom grade (ie you can run a DOP/PAO leak test on it and mechanically they do hold up well during transportation due to aluminium frames etc), they do state efficiencies at 0.1 microns etc.
0.1 microns and those ultrafine particle sizes are captured by the HEPA fibres with a process called DIFFUSION.
3. Diffusion – particles that are very small (less than 0.1 microns), are delayed and impeded in their path through the filter and will not follow the air’s streamlined path because they will collide with the gas molecules. This behavior is the same to Brownian motion. The delayed path raises the possibility of the particle to be captured by either interception or inertial impaction. Diffusion mechanism, at lower air flow speed, is dominant.