Air purifiers with HEPA filters
The first HEPA filter has been created during the 1940s and used for the "Manhattan Project" to avoid contaminant leaks. For many decades, these filters have never stopped to evolve to satisfy the air quality increasing request for many technological industries. These technologies can be used today for offices and houses. HEPA filter’s efficiency is at least 99.97 % on the particles higher than 0.3 microns, what makes it one of the most efficient technologies. Other filters have also an activated carbon layer to filters chemical substances (formaldehyde, VOC ...), gas and odours. You are guaranteed to breathe an air as pure as in full nature.