7 ms·

Rethinking indoor air chemistry

musha68k 4y ago
Somewhat illogical that after more than two years into the pandemic HEPA filters are still a rare sight to be seen indoors. So chemical compounds in general yes, but especially aerosols-as-viral-vector still pose a threat: https://elpais.com/especiales/coronavirus-covid-19/a-room-a-bar-and-a-class-how-the-coronavirus-is-spread-through-the-air/ https://elpais.com/especiales/coronavirus-covid-19/a-room-a-...
- ceejayoz 4y ago
  > Somewhat illogical that after more than two years into the pandemic HEPA filters are still a rare sight to be seen indoors. I think we'll look back at this particular thing as one of the greatest public health failures in quite some time.
  - colineartheta 4y ago
    Can you name a greater one?
    - ceejayoz 4y ago
      Not banning smoking probably is up there.
- crazygringo 4y ago
  Really? I feel like they've popped up everywhere, never seen so many air filters in my life. I feel like every doctor's reception area, daycare, dance studio, meeting room... every little public room that doesn't have HVAC has a little air filter in the corner or on a side table. Often one the Levoit air purifiers that got so crazy popular on Amazon. As to whether they replace the filters regularly enough, I have no idea... I also figure they have little-to-no effect when 20 people are in the room and its fan is on its weakest (quietest) setting.
  - musha68k 4y ago
    That sounds great, I guess it depends on local context then. Agree on maintenance and adjusted usage.
ballenf 4y ago
Could the shift away from full spectrum incandescent bulbs have any affect on the "air cleaning" process indoors?
Cupertino95014 4y ago
Granted that not everyone lives in a friendly climate: * What's the effect of occasionally opening a window? I'm not talking about all day when it's 20F or 105F outside, but for half an hour at least.
- ladberg 4y ago
  Not exactly what you're asking but here's an anecdote: I recently got an air quality monitor because I was worried about CO2 levels in my apartment having the windows closed and AC running all day every day. It turns out the levels were higher than I'd like (nearly 2000 PPM) and just cracking a few windows open very slightly, less than an inch, is enough to reduce the concentration to between 400 (outside air) and 900 depending on how many people are home. The window AC unit was still able to handle cooling the apartment with a relatively small change in usage. I also run an air filter constantly so my PM2.5 and PM10 levels were already near-zero, but I'd imagine cracking a window helps with that.
  - Cupertino95014 4y ago
    I'm just waiting for a "green building" code to specify "all windows shall open." Imagine the panic that would cause in the construction industry.
    - danans 4y ago
      Building codes already require operable windows, and some local codes now require active ventilation systems.
      - Cupertino95014 4y ago
        The stock of office buildings probably turns over fairly slowly. I've actually never worked in an office where the windows opened.
    - abstract_put 4y ago
      I think generally "green building" (at least the mainstream stuff) focuses on insulation + air tightness, and then mechanical ventilation. In that context, operable windows would be mostly be a "just in case of overheating" or similar, and the expectation would be CO2 et al would be managed by the ventilation.
solidist 4y ago
I wouldn't overthink it. Opening windows frequently is a good thing. Doing it during winter is even better. Oh and use crbon/hepa air filtering in bedrooms while sleeping.
elina123 4y ago
danans 4y ago
> Ozone was added to the chamber air inflow in a quantity that was not harmful for humans but representative of higher indoor levels Just in case anyone reads this and is thinking about buying one of the ozone emitting "air cleaners": https://www.epa.gov/indoor-air-quality-iaq/ozone-generators-are-sold-air-cleaners https://www.epa.gov/indoor-air-quality-iaq/ozone-generators-... "The same chemical properties that allow high concentrations of ozone to react with organic material outside the body give it the ability to react with similar organic material that makes up the body, and potentially cause harmful health consequences. When inhaled, ozone can damage the lungs"
- Chris2048 4y ago
  Maybe they can be used while rooms are not occupied? That said, would there be any wear/damage on items within the room?
  - danans 4y ago
    > Maybe they can be used while rooms are not occupied? Yes, but a simple exhaust fan in a window could also be used without any risk to the occupant. If there's no window, then one should definitely not introduce ozone. > That said, would there be any wear/damage on items within the room? "Ozone can cause substantial damage to a variety of materials such as rubber, plastics, fabrics, paint and metals. Exposure to ozone progressively damages both the functional and aesthetic qualities of materials and products, and shortens their life spans." https://ww2.arb.ca.gov/resources/fact-sheets/ozone-effects#:~:text=Ozone%20can%20cause%20substantial%20damage,%2C%20fabrics%2C%20paint%20and%20metals https://ww2.arb.ca.gov/resources/fact-sheets/ozone-effects#:....
    - cma 4y ago
      It does much more than airing out. It will completely clear up cigarette smell from an apartment that had indoor smoking. It neutralizes. All the gunk that built up from it, similar to how it degrades rubber.
      - 4y ago
giantg2 4y ago
I think my potent chemicals are coming from sources other than my skin and breath.

Somewhat illogical that after more than two years into the pandemic HEPA filters are still a rare sight to be seen indoors. So chemical compounds in general yes, but especially aerosols-as-viral-vector still pose a threat: https://elpais.com/especiales/coronavirus-covid-19/a-room-a-bar-and-a-class-how-the-coronavirus-is-spread-through-the-air/ https://elpais.com/especiales/coronavirus-covid-19/a-room-a-...

ceejayoz 4y ago
> Somewhat illogical that after more than two years into the pandemic HEPA filters are still a rare sight to be seen indoors. I think we'll look back at this particular thing as one of the greatest public health failures in quite some time.
- colineartheta 4y ago
  Can you name a greater one?
  - ceejayoz 4y ago
    Not banning smoking probably is up there.
crazygringo 4y ago
Really? I feel like they've popped up everywhere, never seen so many air filters in my life. I feel like every doctor's reception area, daycare, dance studio, meeting room... every little public room that doesn't have HVAC has a little air filter in the corner or on a side table. Often one the Levoit air purifiers that got so crazy popular on Amazon. As to whether they replace the filters regularly enough, I have no idea... I also figure they have little-to-no effect when 20 people are in the room and its fan is on its weakest (quietest) setting.
- musha68k 4y ago
  That sounds great, I guess it depends on local context then. Agree on maintenance and adjusted usage.

ballenf 4y ago

Could the shift away from full spectrum incandescent bulbs have any affect on the "air cleaning" process indoors?

Cupertino95014 4y ago

Granted that not everyone lives in a friendly climate: * What's the effect of occasionally opening a window? I'm not talking about all day when it's 20F or 105F outside, but for half an hour at least.

ladberg 4y ago
Not exactly what you're asking but here's an anecdote: I recently got an air quality monitor because I was worried about CO2 levels in my apartment having the windows closed and AC running all day every day. It turns out the levels were higher than I'd like (nearly 2000 PPM) and just cracking a few windows open very slightly, less than an inch, is enough to reduce the concentration to between 400 (outside air) and 900 depending on how many people are home. The window AC unit was still able to handle cooling the apartment with a relatively small change in usage. I also run an air filter constantly so my PM2.5 and PM10 levels were already near-zero, but I'd imagine cracking a window helps with that.
- Cupertino95014 4y ago
  I'm just waiting for a "green building" code to specify "all windows shall open." Imagine the panic that would cause in the construction industry.
  - danans 4y ago
    Building codes already require operable windows, and some local codes now require active ventilation systems.
    - Cupertino95014 4y ago
      The stock of office buildings probably turns over fairly slowly. I've actually never worked in an office where the windows opened.
  - abstract_put 4y ago
    I think generally "green building" (at least the mainstream stuff) focuses on insulation + air tightness, and then mechanical ventilation. In that context, operable windows would be mostly be a "just in case of overheating" or similar, and the expectation would be CO2 et al would be managed by the ventilation.

solidist 4y ago

I wouldn't overthink it. Opening windows frequently is a good thing. Doing it during winter is even better. Oh and use crbon/hepa air filtering in bedrooms while sleeping.

elina123 4y ago

danans 4y ago

> Ozone was added to the chamber air inflow in a quantity that was not harmful for humans but representative of higher indoor levels Just in case anyone reads this and is thinking about buying one of the ozone emitting "air cleaners": https://www.epa.gov/indoor-air-quality-iaq/ozone-generators-are-sold-air-cleaners https://www.epa.gov/indoor-air-quality-iaq/ozone-generators-... "The same chemical properties that allow high concentrations of ozone to react with organic material outside the body give it the ability to react with similar organic material that makes up the body, and potentially cause harmful health consequences. When inhaled, ozone can damage the lungs"

Chris2048 4y ago
Maybe they can be used while rooms are not occupied? That said, would there be any wear/damage on items within the room?
- danans 4y ago
  > Maybe they can be used while rooms are not occupied? Yes, but a simple exhaust fan in a window could also be used without any risk to the occupant. If there's no window, then one should definitely not introduce ozone. > That said, would there be any wear/damage on items within the room? "Ozone can cause substantial damage to a variety of materials such as rubber, plastics, fabrics, paint and metals. Exposure to ozone progressively damages both the functional and aesthetic qualities of materials and products, and shortens their life spans." https://ww2.arb.ca.gov/resources/fact-sheets/ozone-effects#:~:text=Ozone%20can%20cause%20substantial%20damage,%2C%20fabrics%2C%20paint%20and%20metals https://ww2.arb.ca.gov/resources/fact-sheets/ozone-effects#:....
  - cma 4y ago
    It does much more than airing out. It will completely clear up cigarette smell from an apartment that had indoor smoking. It neutralizes. All the gunk that built up from it, similar to how it degrades rubber.
    - 4y ago

giantg2 4y ago

I think my potent chemicals are coming from sources other than my skin and breath.