4 ms·

Is there any evidence that the virus can survive passage through a normal air filter/AC system and infect humans?

javajosh 6y ago
That's a difficult thing to test directly, so I think most people reason it out. In this case, you think about the virus, its interaction with air particles, and the interaction with a typical AC system with and without (unheated) filtration. I think the issue with ordinary filtration is that the virus is very small and can pass through most filters; by heating it the virus only needs to collide with the hot filter once, or (I think) get knocked around by fast air molecules to become unviable (is "killed" the right term for a virus that may not be "alive"?) Long story short, I think this invention looks great and I for one would use one, especially in cold climates where I already want to heat up the air.
- stubish 6y ago
  > Long story short, I think this invention looks great and I for one would use one, especially in cold climates where I already want to heat up the air. If it also works on influenza, it would be a fantastic way to heat buildings during flu season, and the investment could pay for itself even after the current COVID pandemic.
ipsum2 6y ago
https://wwwnc.cdc.gov/eid/article/26/7/20-0764_article https://wwwnc.cdc.gov/eid/article/26/7/20-0764_article > During January 26–February 10, 2020, an outbreak of 2019 novel coronavirus disease in an air-conditioned restaurant in Guangzhou, China, involved 3 family clusters. The airflow direction was consistent with droplet transmission. To prevent the spread of the virus in restaurants, we recommend increasing the distance between tables and improving ventilation.
- belltaco 6y ago
  The virus didn't come through the ac system in that case. The AC was just blowing air from the infected person to others. This solution would have been useless.
saeranv 6y ago
Another solution I have thought about is simple increasing the amount of fresh air brought into an indoor space. Laboratories, wood-working shops and other spaces that can produce unhealthy air have extremely high Air Change per Hour (ACH)[1] requirements. It's wasteful[2] since you also have to condition that air, but it seems like a simple solution to ensuring we dilute air swarming with potential virus. [1] https://www.engineeringtoolbox.com/air-change-rate-room-d_867.html https://www.engineeringtoolbox.com/air-change-rate-room-d_86... [2] You can limit it a little bit with demand control ventilation, which monitors C02 exhaled by occupants and tunes ventilation accordingly.
- dehrmann 6y ago
  > It's wasteful since you also have to condition Heat exchangers can help, but it's still obviously less efficient.
  - saeranv 6y ago
    Yes, and another big saver would be certain types of heat recovery system[1] that will allow you to recover the heat added to the supply air from the exhaust air without mixing (and thereby polluting) the air streams. [1] https://en.wikipedia.org/wiki/Heat_recovery_ventilation#:~:text=Heat%20recovery%20is%20a%20method,thus%20energy%20costs%20)%20of%20buildings.&text=Heat%20recovery%20systems%20typically%20recover,the%20energy%20efficiency%20of%20buildings%20 https://en.wikipedia.org/wiki/Heat_recovery_ventilation#:~:t....
redis_mlc 6y ago
FYI: Legionnaires' Disease is spread through HVAC systems that use cooling towers: https://en.wikipedia.org/wiki/Legionnaires'_disease https://en.wikipedia.org/wiki/Legionnaires'_disease
- hedora 6y ago
  That’s because the cooling towers incubate the bacteria that causes Legionnaires. COVID is caused by a virus that won’t reproduce outside of mammals.
bradknowles 6y ago
Yes. Why do you think hospitals have HEPA filters in the first place?

That's a difficult thing to test directly, so I think most people reason it out. In this case, you think about the virus, its interaction with air particles, and the interaction with a typical AC system with and without (unheated) filtration. I think the issue with ordinary filtration is that the virus is very small and can pass through most filters; by heating it the virus only needs to collide with the hot filter once, or (I think) get knocked around by fast air molecules to become unviable (is "killed" the right term for a virus that may not be "alive"?) Long story short, I think this invention looks great and I for one would use one, especially in cold climates where I already want to heat up the air.

stubish 6y ago
> Long story short, I think this invention looks great and I for one would use one, especially in cold climates where I already want to heat up the air. If it also works on influenza, it would be a fantastic way to heat buildings during flu season, and the investment could pay for itself even after the current COVID pandemic.

ipsum2 6y ago

https://wwwnc.cdc.gov/eid/article/26/7/20-0764_article https://wwwnc.cdc.gov/eid/article/26/7/20-0764_article > During January 26–February 10, 2020, an outbreak of 2019 novel coronavirus disease in an air-conditioned restaurant in Guangzhou, China, involved 3 family clusters. The airflow direction was consistent with droplet transmission. To prevent the spread of the virus in restaurants, we recommend increasing the distance between tables and improving ventilation.

belltaco 6y ago
The virus didn't come through the ac system in that case. The AC was just blowing air from the infected person to others. This solution would have been useless.

saeranv 6y ago

Another solution I have thought about is simple increasing the amount of fresh air brought into an indoor space. Laboratories, wood-working shops and other spaces that can produce unhealthy air have extremely high Air Change per Hour (ACH)[1] requirements. It's wasteful[2] since you also have to condition that air, but it seems like a simple solution to ensuring we dilute air swarming with potential virus. [1] https://www.engineeringtoolbox.com/air-change-rate-room-d_867.html https://www.engineeringtoolbox.com/air-change-rate-room-d_86... [2] You can limit it a little bit with demand control ventilation, which monitors C02 exhaled by occupants and tunes ventilation accordingly.

dehrmann 6y ago
> It's wasteful since you also have to condition Heat exchangers can help, but it's still obviously less efficient.
- saeranv 6y ago
  Yes, and another big saver would be certain types of heat recovery system[1] that will allow you to recover the heat added to the supply air from the exhaust air without mixing (and thereby polluting) the air streams. [1] https://en.wikipedia.org/wiki/Heat_recovery_ventilation#:~:text=Heat%20recovery%20is%20a%20method,thus%20energy%20costs%20)%20of%20buildings.&text=Heat%20recovery%20systems%20typically%20recover,the%20energy%20efficiency%20of%20buildings%20 https://en.wikipedia.org/wiki/Heat_recovery_ventilation#:~:t....

redis_mlc 6y ago

FYI: Legionnaires' Disease is spread through HVAC systems that use cooling towers: https://en.wikipedia.org/wiki/Legionnaires'_disease https://en.wikipedia.org/wiki/Legionnaires'_disease

hedora 6y ago
That’s because the cooling towers incubate the bacteria that causes Legionnaires. COVID is caused by a virus that won’t reproduce outside of mammals.

bradknowles 6y ago

Yes. Why do you think hospitals have HEPA filters in the first place?