HEPA filters and COVID-19. HEPA (high efficiency particulate air) filters claim to filter particles down to 0.3 microns (0.3 micrometres, or 300 nanometres). Most viruses vary in diameter from a mere 20 nanometres (that's 0.02 microns, or 0.00002mm) up to 400nm (0.4 microns) – some are bigger still. BEST OVERALL: Express Water Heavy Metal Whole-House Water Filter. BEST BANG FOR THE BUCK: GE GXWH04F Water System. BEST FILTER/SOFTENER COMBO: Aquasana EQ-1000-AST-UV Whole-House Filter. BEST 1 To answer this question, we need to first answer if HEPA filters can capture particles as small as viruses, such as the coronavirus. The COVID-19 coronavirus measures 0.06 – 0.14 microns in diameter. HEPA filters – the workhorse of any purifier – must remove 99.97% of particles “greater than or equal to” 0.3 microns. Cellulose/polymer matrix-based polymer composites for air purification. Dual-size TEMPO oxidised CNFs/PVP nanofibers composites of submicron and nano size were spun onto HEPA filter via one-step electrospining technique to obtain a multilayer air filter ( Balgis et al., 2017) ( Table 9 ). Four-zone climate control with nano-particle filters will soon be optionally available for the BMW 5 Series and M5. The system also includes an air flush mode, which cleanses most of the cabin air in a matter of minutes. Cabin air can be exchanged manually, or as part of pre-drive conditioning in the BMW ConnectedDrive app. —Alex Tock. On the other hand, replacing a carbon-activated filter costs you about $50 and you need to do it every 3 months. The maintenance costs can vary depending on the specific brand, model, and usage patterns of both devices. But as a whole, an ionic air purifier is going to be about 2 times cheaper. Winner: Ionizer is easy for the purse. When looking at the “cost-per-unit-air-cleaned,” the study said that “the DIY air filter is approximately one-tenth the initial cost of a commercially available HEPA-based air cleaners Sorted by: 2. A HEPA filter is defined as one which removes 99.97 of all particulates larger than 3 micrometers it does so by creating a pressure differential between it's input and output between which is placed a fine filter with as large a surface area to trap particulates as to fit its specification. Depends on your setup, Air extracted .

nano filter vs hepa filter