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Take Charge of Air Quality

Doubling a room's air changes per hour (ACH) halves accumulation & transmission risk for airborne pathogens.

Well-maintained HVAC top out around 4-6 air changes per hour (ACH). Older buildings may only get 2-3 ACH.  Pre-pandemic, only hospital isolation and operating rooms were designed for 12 ACH.


Adding a Tower of Power to large rooms like classrooms (~900 sq ft) with legacy 2-3 ACH ventilation will double cleaning rates into 5-6 ACH range.  Multiple studies have shown 70-82% reduction in COVID transmission rates for this range.  Two Tower of Power can boost an already good 5-6 ACH classroom to excellent 10-12 ACH.  Smaller CleanAirKits can do the same for medium rooms (~450 sq ft). 

Affordably Safer Spaces

What if we boosted shared spaces like classrooms, restaurants, dining & family rooms to 12-20 ACH, the range of hospital isolation & operating rooms? Infection risk should lower towards outdoors, with 1/20 the rate of indoor transmission.

HEPA purifiers don't clean fast, quiet, or affordably enough to reach this goal in most rooms.  DIY Corsi Rosenthal cubes can, but are often rejected for their noise & bulk.

Clean Air Kits have perfected the C-R strategy pairing powerful fans with high-flow MERV13 filters.  Our banks of silent pressure fans match CR Box capacities at 1/5 noise, 1/5 power, and half the footprint.  We bring you an affordably silent breakthrough in bulk air purification.

WARNING:  Just like outdoor transmission still occurs in crowds and speaking face to face, air cleaning is not a substitute for well-fitted n95 masks in close interactions.  Air cleaning complements masking to speed pathogen removal at a distance and increase safety for people well-separated from a contagious source.  For two layers of protection in indoor gatherings, ask guests for same-day rapid COVID tests or wearing n95 masks in addition to air filtering.

The Economics of Clean Air in Schools

In 2021 congress made billions in grants available to upgrade school HVAC systems toward 6 ACH and provide 1 HEPA purifier per classroom.  Some schools HVAC were upgraded quickly, some are still in progress, and others used the money elsewhere.  Most of the HEPA have been turned down or unplugged because they're disruptively loud (50-60 dB) at full blast and thus not contributing as much clean air as planned.  ANSI standards actually specify (unreasonably?) low noise <= 35 dB for classroom purifiers -- a quietness no HEPA manufacturer can achieve at significant clean air delivery rates.  The 35dB level was chosen to ensure every student can still hear their teacher perfectly.

Corsi-Rosenthal's MERV13 strategy, especially driven by quiet PC fans, can quietly change the economics of classroom clean air.  For instance, two 7-fan SickleFlow Luggables (list price $244 each) can add 5 ACH to a standard classroom, cutting pathogen transmission rates a further 50-80% depending on existing HVAC air changes per hour.  The United States has about 2 million primary & secondary classrooms, so EVERY standard classroom in the United States could be boosted by 5 ACH for less than a billion dollars!  That's probably less money than has been spent lobbying against clean air!  And a pittance compared to the billions lost each year from increased teacher & student absences and health care costs.

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