![](https://cleanair.camfil.us/wp-content/uploads/2014/07/Air-Filters-Update-Particle-Pollution-The-Invisible-Danger2.jpg)
Impossible to see, harmful indoor particles can trigger illness, even death — but effective air filtration can beat back the threat
Impossible to see, harmful indoor particles can trigger illness, even death — but effective air filtration can beat back the threat