update Dec 31 in first post Ventilation, indoor air quality and CO2

[wathe]

As some of you know, I've recently acquired a portable CO2 monitor.  I thought it might be useful for me to post my results.  I will update in OP whenever I get new or interesting data.  

Quality of ventilation in public spaces isn't something that's generally public knowledge or easy to judge just by looking, and it seems to be very important with respect to risk of covid transmission.    I think air quality in public spaces will be one of next our big public health challenges to manage.

The ppm of CO2 in an indoor space can be used to assess the quality of ventilation in the space.  We all breathe out CO2, and it will accumulate in poorly ventilated spaces that have people in them.  The higher the CO2 level, the higher the fraction of other people's breath is in the ambient air (and that we are breathing in), and this can be used as a proxy for how much other respiratory aerosols are floating around - such as covid-bearing aerosols.

There are limits: 1) It does not tell you anything about filtration - HEPA filters remove particles including virus laden aerosols, but do not scrub out CO2.  So recirculated well-filtered, clean air might have a not-so-great CO2 reading (ie on an airplane) 2) Combustion will also add CO2 to the air, so not useful for this purpose  in places where that's an issue (certain industrial spaces).

Swiss study that linked CO2 of >2000ppm in classrooms to a six times higher covid rate than classrooms with CO2< 2000ppm

For reference:

Outdoor air 420 ppm

Hospital/healthcare facility standard in my province <600 ppm

As per device manufacturer:

Good ventilation less than 1000 ppm CO2

Average ventilation 1000-1400 ppm

Bad ventilation  >1400 ppm

(I haven't yet read up on the science that supports these values - no time! - but I am most interested in relative values from venue to venue.  So take them for what they are worth)

Local hospital, the vaccine clinic, and the local covid clinic have excellent ventilation:  400's with occasional rises into the 500's.  I am so pleased to know as a fact.

The local Canadian Tire (big-box sized store, modern construction) also has excellent ventilation, 450-570 ppm

The heritage church basement room where some of our scouting sections meet has terrible ventilation. 10 people in a good sized room that did not feel crowded.  Electric heater thingy's on the wall, no ductwork.  Levels started at 700, climbed steadily over an hour to almost 1400 with no change in slope and no signs of levelling off, at which point we cracked a window and cracked a door (less than one inch) and left them cracked for exactly 5 minutes.  Level fell to 800's.  Lesson learned: cracking a couple of windows makes a big difference.

The ventilation in my house is less good than I thought it would be, since we run a heat recovery ventilator constantly in the winter.  600's baseline, climbs to 1100's and stays there when we are all in the kitchen all day doing school.  Less of a big deal with my immediate family bubble, but definitely incentive for me to crack windows and run the Corsi-Rosenthal box when we have guests visiting over Christmas.

Update 12/19:

Interesting:  The house CO2 falls to low 900's in the kitchen with us all in it (from low 1100's) if I run the Corsi-Rosenthal box.  It doesn't scrub CO2, but it sure does move air, diluting the CO2 by admixing with air from all around the house, I think.

Compact car with single occupant for 20 min, with venting set as usual for time of year (fresh air, defrost, low fan speed) 550-650 ppm range.

Local pizza place (old strip mall) 900 ppm.  DH was in there for less than a minute, so level might actually be higher if device didn't have time to get a true reading - I think that this is likely.

Update 12/21:

Local Coscto surprisingly poor for such a huge space at 960-970 ppm.  Very new construction (within the last 5 years).  Store was busy but not at all crowded - no line-up to cash out.  I was in there for 45 minutes.  Levels were consistent throughout the store.

Local small pharmacy good at 600's

Local car dealership showroom poor at 900's, back office good at 600's

Lesson learned: You can't tell about ventilation quality just by looking.  Big, airy spaces might be poor (Costco) and small dingy-looking spaces might be quite good (back offices of car-dealership, small pharmacy)

Update March 4, 2022

I've had my monitor with me to lots of places now.  Results are interesting (to me, anyway)

Most grocery stores and big box stores sit 600-1000 ppm.  It's impossible to predict just by looking which stores do well a which don't.  Also, individual stores tend to be consistent from trip to trip.  My local Costco seems to always sit 900-1000, and my local Canadian Tire in the 500 range.

The hospital is reliably at less than 550 ppm, even in smallish rooms with the door closed, or at crowded nursing stations.

Various homes we've visited sit at 800-1100 ppm while guests are present (this is during Canadian winter, relying on mechanical and passive ventilation.  Windows are generally closed).

I've had it in several church basements, and they have all been bad.  As high as 1500pm within an hour or two of a group occupying the space.  None are new construction; the newest is, I think, built in the 1960's.  So not super-modern ventilation systems.

The biggest surprise was a very large gym during a volleyball tournament.  We still have public health restrictions in place with capacity limits, so not crowded - teams were limited to players, coaches, and one parent per player.  The gym was huge: 3 volleyball courts, plus basket ball court and indoor soccer, all in the same space separated by netting. High ceilings.  By the end of the day, the CO2 was 1773 ppm -  the worst I've recorded in any public space thus far.  DH used the real-time data to pull DS out of the gym for lunch instead of eating in the gym with the team.  DS  plays masked, but obv would have to unmask to eat.  We had decided beforehand that the threshold for eating inside would be 800 ppm.  So, the monitor gave us real-time data that influence decision making. A win, for sure.

We also had our first family long car trip of the pandemic recently.  4 people, 7 hours in a car.  CO2 in the 800's in the car for the trip.  Except for a stop at a grocery store upon arrival:  The teens stayed in the car,  and the CO2 shot up to 1536 ppm during the 20 min they were in there without the ventilation running (car turned off, windows closed, outdoor temp -7C). It took 45 min for it to fall back to 800 (driving with the ventilation running, windows closed, 4 occupants).  Lesson learned!

I haven't been brave enough to go to a restaurant yet.

Update March 12, 2022

More evidence that you can't assess ventilation just by looking:

Volleyball tournament at a large convention centre.  The courts were in the main exhibit hall, which is a huge space: 82,000 square feet, with 60 feet of open air between the floor and roof (30 feet of clear ceiling height, then 30 more feet of open rafters and exposed duct etc).  The space was busy, but not crowded and absolutely  well below capacity.  CO2 peaked at 1348 by early afternoon, with a steady slope.  I expect it continued to rise over the course of the evening while the second wave of teams played - (our wave was done by 3pm, and we were followed by a second wave that runs until 10pm).  The much smaller ballroom was used for team hangout space.  Lower ceilings, more crowded - definitely more people per square foot.  It sat at 700's.   So did the lobby - which was relatively crowded with teams and families hanging out all day.  Totally the opposite of what you would guess just by looking.  The big, airy-looking space had relatively worse ventilation than the smaller, crowded-looking space.

Update March 27, 2022

Record so far for worst ventilated space I've been to:  Private sportsplex - a very large 80 000 square foot converted warehouse, housing several indoor soccer fields, basketball courts, and volleyball courts in one giant space, each field/court separated by netting.  No evidence of any mechanical ventilation system (there were ceiling fans and ceiling mounted space-heaters only.  No ducts or vents that I could see.  The ceiling was open rafters - if there were vents or ducts, I should have been able to see them).  CO2 peaked at a whopping 2988ppm.  Never fell below 2000pmm in the 4 hours that we were there.  Mask mandates were lifted here on Monday.  Waste water has been trending steeply up.  This place was covid soup.  DS played in an N95 respirator - this will be his real-life fit-test, I think.

 

ETA:  I've also been monitoring my hospitals levels at intervals, as I expect that ventilation may change with the seasons.  It has been consistently excellent, with levels never above 550ppm, even in small room with closed doors.

Update April 22, 2022

New personal record for worst CO2 in an indoor public space:

Ontario Volleyball Association championship tournament at the RIM Centre in Waterloo.  This is a giant, modern athletic facility with 4 ice rinks, multiple gyms and an enormous field house.  All of these areas were set up for volleyball.  Busy with people, but did not appear to be at capacity - plenty of empty bleacher space.  Obvious mechanical ventilation (visible ducts and vents), which seemed to be turned on (could near humming/ventilation noises first thing in the am when the place was quiet).  CO2 peaked in the field house at 3006ppm.  And I was seated right next to an emergency exit door that had an obvious draft - so probably actually worse than that.  Ice pads peaked at 2018ppm.  Also, we were in the morning wave.  CO2 likely climbed further during the afternoon and evening sessions; the slope of the CO2 rise appeared constant, with no sign of levelling off.  Masks optional.  More unmasked than masked spectators, and very few masked athletes.  My poor kid played for 3 days in an n95 - he is a very good sport about it.

Lesson learned:  even very modern, large spaces that appear well ventilated can actually have inadequate ventilation.

 

Update August 2022:

I took the thing camping (because of course I did)

Air quality in our tent was surprisingly bad!  As high as 1400 ppm.  This is for 4 people a 6 person car-camping chateau of a tent, that, as tents go, has great ventilation (or so I thought).  Big screen windows that we kept at least 1/3 open all the time.  Windy nights had better numbers (800's) and still, calm nights worse numbers.  CO2 would rise noticeably even just from slipping into the tent for a few minutes during the day to change clothes.

CO2 numbers sitting around the campfire were much better than I thought they would be.  I thought that sitting close to a combustion source would raise local CO2, but it didn't much.  Readings were still under 500 sitting around a pretty intense campfire - the kind you have to move back from because it's too intensely hot to sit too close.  Good ventilation in the open air seems obvious, of course, but I was still surprised.

Data for Ontario Provincial park users:  The showers were great, ppm in the 500s at peak. The comfort stations (flush toilet facilities) were bad, ppm 900-1000; pit privies fantastic, ppm peaking at 500s

Update August 31, 2022:

More camping data:  Backpacking tent, full fly, roof-vents open, vestibule closed, single occupancy.  On a still night, peak 2455 ppm CO2 while getting changed and into sleeping bag, the fell to about 1800 ppm and held steady there for most of the night, then dropping to about 1600 ppm in the early morning, spiking back up to 2000 while getting ready for the day and packing up sleeping gear.  On a windy night (windy enough that I could feel a draft inside the tent) with the same tent "settings", similar peaks during bedtime and morning getting ready/packing, but falling to 800's while asleep.

Lessons:  1)Physical activity, even very modest, low level activity (I was sitting packing/unpacking and physically getting in and out of a sleeping bag, not doing a workout), in a confined space can really shoot up the CO2.  2) passive ventilation is very variable, depending on wind I think.

Update Sept 8, 2022

One of our kids is transitioning from homeschool to public highschool this year.  This is the first week of school.  The monitor went with the kid in his backpack (of course).  The school was built in the 70's.  I don't think that the windows open.  I know that some of the classrooms don't have any windows at all.

School bus: 1583 ppm morning run, 1221 ppm afternoon run.  The bus is not crowded.  Windows closed.  I think I will have him ask if windows are allowed to be opened.

Classroom: Low 900's morning periods, high 900's afternoon periods.  Corridors between classes peak 1025ppm

 

Update November 9, 2008

Car, single occupant, 20km trip to work that is mostly rural highway with a cruising speed of 90kph, fan speed 4/7, ventilation set to recirculate: peak CO2 1743ppm.  Steep slope throughout - the CO2 would have kept on rising if the trip had been longer.

Return trip: Car, single occupant, 20km trip to work that is mostly rural highway with a cruising speed of 90kph, fan speed 4/7, ventilation set to fresh air: peak CO2 563ppm.  Peaked at the beginning of the trip (probably reflects the minute or two it takes me to get situated in the car and turn it on,during which no ventilation)

Ventilation settings matter!  Especially relevant when ride-sharing or taking a taxi, I should think.

 

.  

Kid's school:  Classrooms regularly sit at 1100ppm.  I am not pleased.

Adding:

Two nights in a single tent, full fly, vents open.  CO2 exceeded 3000ppm at peak.  CO2 peaks at the beginning and the end of the night, when I'm busy/moving around getting changed and getting things set up or packed.  Falls to a more respectable 1500 or so while sleeping.  

 

 

***UPDATE December 31, 2022***

The  Aranet gave me a very low battery warning today.  These are the original AA's from way back in Dec 21.  So, battery life is more than a year.  That's with constant use; I have never turned it off.  Pretty good.

Some personal bad air records:  1) A high school gym during a day-long volleyball tournament.  Peak CO2 3871ppm!  The slope rose steadily throughout the day.  There was visible ducting for mechanical ventilation, but no way to know if it was actually turned on.  There were 4 HEPA units in the 3 three gyms, but none were plugged in (I took care of that for them....). 2) DH and the kids waiting in the car for 20 min, with the engine off and the windows closed, CO2 4327 ppm!

 

Edited January 1, 2023 by wathe

[happi duck]

Thanks for posting this!  Interesting stuff!

I don't think people think about the air enough.  I just remarked today that I thought by now public places would post what sort of ventilation they have or there'd be scores or such posted.

Tracking air quality seems like something my brother and I could get into.  *approaches rabbit hole*

[Ausmumof3]

Thank you! I really appreciate you taking the time to type out and share this.

[Arcadia]

14 minutes ago, happi duck said:

 

I don't think people think about the air enough.  I just remarked today that I thought by now public places would post what sort of ventilation they have or there'd be scores or such posted.

It is very costly to retrofit HVAC systems. My condo neighbors spent quite a substantial amount for a two bedroom unit (about 1200sqft). Schools spent huge sums on retrofitting HVACs that are not up to spec anymore.

My respiratory system is unfortunately very sensitive to air quality especially indoors. I have ran a mild fever just from bad air quality at stores. Its related to sick building syndrome https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2796751/

[wathe]

The monitor is the Aranet4.  I meant to put that in my post.

[bookbard]

Yes, I bought a portable CO2 meter and had it on at work. It is about 8x4 metre squared I think, with an entry and exit door at either end. As soon as both doors were closed the levels went through the roof and the alarm went off! With both doors open, it was 440 or whatever - same as outdoors.

Technically, we're supposed to keep both doors closed for security reasons. I usually keep them open, but I also bought a good air filter and I keep that running. That plus masks is the best I can do - anyone can walk in off the street to talk to us, and now they don't legally need to wear masks. I did do a tally the other day though and 3/4 were still wearing them. 

[Laura Corin]

We have CO2 monitors in classrooms at work but not offices. One classroom - as I predicted  - immediately breached limits. It's just possible to use it with the window full open, but on a day of high winds - the building stands on a cliff - that's not practical.  

The main administrative office is staffed by people who don't think to wear a sweater to work. It's hot and stuffy, with the cracks around drafty old windows stuffed. I go in there if I have to but don't remove my heavy-duty mask for any purpose. 

I keep my own office window open, facing onto the sea, gale or no gale.

Luckily, the Scottish government is now asking us to work from home if we can.

[wathe]

Update in OP

[wathe]

Update 12/21 in OP

[KSera]

6 minutes ago, wathe said:

Update 12/21 in OP

Thanks for sharing these; I find it really interesting. I left my unoccupied dining room window open an inch for several hours, and only dropped to 607. I had hoped for better than that, but maybe that’s not reasonable of me. My dining room tends to get high readings, which is why I was seeing if an open window helped enough. I don’t think hosting any family members in the dining room is going to be a good idea. 

[Pam in CT]

Thank you *so much* for doing this.  Heartened to hear that cracking a couple windows/doors makes that much difference.

[mommyoffive]

Very interesting!! thank you so much for sharing.

[wathe]

Bump - update in first post.

[KSera]

Thanks for the update! I have also found it not always predictable where will have good readings. I wish there was a way to tell how much hepa filtration was improving that. 

[chocolate-chip chooky]

@wathe Thank you. I really appreciate that you share your results. So helpful. Thank you 🌻

[Ausmumof3]

On 12/19/2021 at 1:55 PM, wathe said:

As some of you know, I've recently acquired a portable CO2 monitor.  I thought it might be useful for me to post my results.  I will update in OP whenever I get new or interesting data.  

Quality of ventilation in public spaces isn't something that's generally public knowledge or easy to judge just by looking, and it seems to be very important with respect to risk of covid transmission.    I think air quality in public spaces will be one of next our big public health challenges to manage.

The ppm of CO2 in an indoor space can be used to assess the quality of ventilation in the space.  We all breathe out CO2, and it will accumulate in poorly ventilated spaces that have people in them.  The higher the CO2 level, the higher the fraction of other people's breath is in the ambient air (and that we are breathing in), and this can be used as a proxy for how much other respiratory aerosols are floating around - such as covid-bearing aerosols.

There are limits: 1) It does not tell you anything about filtration - HEPA filters remove particles including virus laden aerosols, but do not scrub out CO2.  So recirculated well-filtered, clean air might have a not-so-great CO2 reading (ie on an airplane) 2) Combustion will also add CO2 to the air, so not useful for this purpose  in places where that's an issue (certain industrial spaces).

Swiss study that linked CO2 of >2000ppm in classrooms to a six times higher covid rate than classrooms with CO2< 2000ppm

For reference:

Outdoor air 420 ppm

Hospital/healthcare facility standard in my province <600 ppm

As per device manufacturer:

Good ventilation less than 1000 ppm CO2

Average ventilation 1000-1400 ppm

Bad ventilation  >1400 ppm

(I haven't yet read up on the science that supports these values - no time! - but I am most interested in relative values from venue to venue.  So take them for what they are worth)

Local hospital, the vaccine clinic, and the local covid clinic have excellent ventilation:  400's with occasional rises into the 500's.  I am so pleased to know as a fact.

The local Canadian Tire (big-box sized store, modern construction) also has excellent ventilation, 450-570 ppm

The heritage church basement room where some of our scouting sections meet has terrible ventilation. 10 people in a good sized room that did not feel crowded.  Electric heater thingy's on the wall, no ductwork.  Levels started at 700, climbed steadily over an hour to almost 1400 with no change in slope and no signs of levelling off, at which point we cracked a window and cracked a door (less than one inch) and left them cracked for exactly 5 minutes.  Level fell to 800's.  Lesson learned: cracking a couple of windows makes a big difference.

The ventilation in my house is less good than I thought it would be, since we run a heat recovery ventilator constantly in the winter.  600's baseline, climbs to 1100's and stays there when we are all in the kitchen all day doing school.  Less of a big deal with my immediate family bubble, but definitely incentive for me to crack windows and run the Corsi-Rosenthal box when we have guests visiting over Christmas.

Update 12/19:

Interesting:  The house CO2 falls to low 900's in the kitchen with us all in it (from low 1100's) if I run the Corsi-Rosenthal box.  It doesn't scrub CO2, but it sure does move air, diluting the CO2 by admixing with air from all around the house, I think.

Compact car with single occupant for 20 min, with venting set as usual for time of year (fresh air, defrost, low fan speed) 550-650 ppm range.

Local pizza place (old strip mall) 900 ppm.  DH was in there for less than a minute, so level might actually be higher if device didn't have time to get a true reading - I think that this is likely.

Update 12/21:

Local Coscto surprisingly poor for such a huge space at 960-970 ppm.  Very new construction (within the last 5 years).  Store was busy but not at all crowded - no line-up to cash out.  I was in there for 45 minutes.  Levels were consistent throughout the store.

Local small pharmacy good at 600's

Local car dealership showroom poor at 900's, back office good at 600's

Lesson learned: You can't tell about ventilation quality just by looking.  Big, airy spaces might be poor (Costco) and small dingy-looking spaces might be quite good (back offices of car-dealership, small pharmacy)

Update March 4, 2022

I've had my monitor with me to lots of places now.  Results are interesting (to me, anyway)

Most grocery stores and big box stores sit 600-1000 ppm.  It's impossible to predict just by looking which stores do well a which don't.  Also, individual stores tend to be consistent from trip to trip.  My local Costco seems to always sit 900-1000, and my local Canadian Tire in the 500 range.

The hospital is reliably at less than 550 ppm, even in smallish rooms with the door closed, or at crowded nursing stations.

Various homes we've visited sit at 800-1100 ppm while guests are present (this is during Canadian winter, relying on mechanical and passive ventilation.  Windows are generally closed).

I've had it in several church basements, and they have all been bad.  As high as 1500pm within an hour or two of a group occupying the space.  None are new construction; the newest is, I think, built in the 1960's.  So not super-modern ventilation systems.

The biggest surprise was a very large gym during a volleyball tournament.  We still have public health restrictions in place with capacity limits, so not crowded - teams were limited to players, coaches, and one parent per player.  The gym was huge: 3 volleyball courts, plus basket ball court and indoor soccer, all in the same space separated by netting. High ceilings.  By the end of the day, the CO2 was 1773 ppm -  the worst I've recorded in any public space thus far.  DH used the real-time data to pull DS out of the gym for lunch instead of eating in the gym with the team.  DS  plays masked, but obv would have to unmask to eat.  We had decided beforehand that the threshold for eating inside would be 800 ppm.  So, the monitor gave us real-time data that influence decision making. A win, for sure.

We also had our first family long car trip of the pandemic recently.  4 people, 7 hours in a car.  CO2 in the 800's in the car for the trip.  Except for a stop at a grocery store upon arrival:  The teens stayed in the car,  and the CO2 shot up to 1536 ppm during the 20 min they were in there without the ventilation running (car turned off, windows closed, outdoor temp -7C). It took 45 min for it to fall back to 800 (driving with the ventilation running, windows closed, 4 occupants).  Lesson learned!

I haven't been brave enough to go to a restaurant yet.

 

 

 

 

 

Very interesting. There was recordings here showing that it shot up dramatically in a school gym during PE - so I think it might be less about the space and more about the exercising happening? I’ll have to see if I can find it.

[Melissa in Australia]

Thanks

 I found it interesting

[Arcadia]

On 12/18/2021 at 7:25 PM, wathe said:

 

The biggest surprise was a very large gym during a volleyball tournament.  We still have public health restrictions in place with capacity limits, so not crowded - teams were limited to players, coaches, and one parent per player.  The gym was huge: 3 volleyball courts, plus basket ball court and indoor soccer, all in the same space separated by netting. High ceilings.  By the end of the day, the CO2 was 1773 ppm -  the worst I've recorded in any public space thus far.  DH used the real-time data to pull DS out of the gym for lunch instead of eating in the gym with the team.  DS  plays masked, but obv would have to unmask to eat.  We had decided beforehand that the threshold for eating inside would be 800 ppm.  So, the monitor gave us real-time data that influence decision making. A win, for sure.

 

1 hour ago, Ausmumof3 said:

Very interesting. There was recordings here showing that it shot up dramatically in a school gym during PE - so I think it might be less about the space and more about the exercising happening? I’ll have to see if I can find it.

We find high ceilings are good for keeping the room cooler during hot weather. However for air circulation, having ventilation windows near the roof and having ceiling fans help.

[Ali in OR]

Thanks for posting--I missed this the first time. I wish the monitor wasn't so expensive--I would love to have one in my classroom. Only two windows open, and the bottom just pushes out max 6". I have them open everyday, have one small air filter going, but have 3 classes a day of 20-30 students. Masks come off March 12 (not my N95! just unmasked students).

[wathe]

10 hours ago, Ausmumof3 said:

Very interesting. There was recordings here showing that it shot up dramatically in a school gym during PE - so I think it might be less about the space and more about the exercising happening? I’ll have to see if I can find it.

 

For sure, CO2 is a function of number of people, physical activity, time, and ventilation.  Clearly in this case, the ventilation was inadequate for the space, which was being used for its intended purpose.

I should  have added that the other gyms we've been to with the team for practices and games sit at about 700-800, with the same amount of physical activity and similar numbers of people per unit area of space as in the badly ventilated gym.  To be fair, the longest we've been in another gym since I started monitoring has been 4 hours, not all day - but the slope on the curve wasn't rising in the other gyms, suggesting that the ventilation was keeping up.  

The CO2 does  reliably shoot up at the end of the session at all the gyms we've been to while the team is crowded together in the lobby awaiting parent pick-up though.   So, we've advised DS that the lobby at pick up time is not a good time to slip your mask off to take a drink.

[Catwoman]

Thank you for taking the time to post these updates — I really appreciate it!!!

[wathe]

11 hours ago, KSera said:

Thanks for the update! I have also found it not always predictable where will have good readings. I wish there was a way to tell how much hepa filtration was improving that. 

I do too.  There must be a way to measure to this - I know that the Boston School system is measuring airborne particulate (but don't seem to be displaying that data)

What I really want to see is real-time, publicly displayed CO2 in all publicly accessible spaces.

Even better would be capacity limits that are tied to air quality (similarly to how they are now currently tied to fire safety criteria)

[wathe]

We also need to work on public air quality "literacy" - some sort of media blitz/public health campaign.

Of note, Canada recently announced a ventilation upgrade tax credit for small business of up to $10 000 per location, max $50 000 per business.  It's probably not nearly enough.

[happi duck]

@wathe

I totally agree with you!

I'm so shocked we don't already have ventilation scores, inspections etc.

[wathe]

We've been in 3 more Canadian homes in the past 3 days.  All range 900 - 1200 ppm.  Age of construction varies from 1960's to very new (less than 5 years old).  

Shout out to Play Value in Ottawa.  Their ventilation is superb at low 500's.  We were in there a long time...

[Teaching3bears]

Thanks for sharing.  I was shocked to hear that a big place with high ceilings like Costco had a much higher score than many smaller places.  I also expected the outdoor air to be much much better than indoor air.  

[Arcadia]

On 3/4/2022 at 10:28 AM, wathe said:

We also need to work on public air quality "literacy" - some sort of media blitz/public health campaign.

Of note, Canada recently announced a ventilation upgrade tax credit for small business of up to $10 000 per location, max $50 000 per business.  It's probably not nearly enough.

How about schools? Here if parents kick a loud enough fuss about air quality in portable classrooms, the HVAC gets evaluated.

https://www.epa.gov/iaq-schools/maintain-portable-classrooms-part-indoor-air-quality-design-tools-schools

“The most common problems with portable classrooms include:

• Poorly functioning HVAC systems that provide minimal ventilation with outside air
• Poor acoustics from loud ventilation systems
• Chemical off-gassing from pressed wood and other high-emission materials, which may be of greater concern because of rapid occupancy after construction
• Water entry and mold growth
• Site pollution from nearby parking lots or loading areas

The effects of poor indoor air quality in portable classrooms are no different than those in permanent classrooms. All school buildings use similar construction and furnishing materials, so the types of chemicals present in indoor air are not likely to be different for portable versus permanent classrooms. However, pressed-wood products which may contain higher concentrations of formaldehyde are used more in the factory-built portable units than in buildings constructed on-site. As result, levels of airborne chemicals may be higher in new portable classrooms, especially if ventilation is reduced.

Although portables are often the lowest cost option for housing students, they range in quality. Care should be taken during specification and selection to ensure that the students' health is not compromised for inexpensive, low quality designs. When districts specify a portable design, they typically create a term contract that other districts can use to purchase the same (or slightly different) design. This practice (often called "piggy-backing") can save a district valuable time and money on specifications and approvals, but it can also compound poor decisions made in the original procurement.”

[wathe]

15 hours ago, Arcadia said:

How about schools? Here if parents kick a loud enough fuss about air quality in portable classrooms, the HVAC gets evaluated.

 

Yes, absolutely yes, ventilation in schools needs to be addressed.  And it's happening here.  I think that fixing ventilation in schools will be relatively easy compared to fixing ventilation in the private sector.  Schools here are decently well funded, and I  think that there is political and public will to make it happen. Private sector, not so much.  I think that ventilation fixes in publicly accessible spaces that are private sector will have to be tied to sustainable business models and make financial sense for business owners.  Right now, there is no financial incentive to be transparent about ventilation or spend $ to improve it.  Tying ventilation to capacity and mandating  public display of indoor air quality data  (the stick), and providing funding/tax credits for upgrades (the carrot) will be necessary, I think.

[wathe]

bump for update in first post

 

 

Edited March 13, 2022 by wathe

[wathe]

bump for update in first post

 

Edited March 27, 2022 by wathe

[prairiewindmomma]

Wowzers. That’s crazy high!! Best wishes you all come away from that safe and well.

[KSera]

18 minutes ago, wathe said:

bump for update in first post

 

Wow. That’s really high. Were the ceilings as high as typical gym ceilings? Or were they lower than that? We tend to think that high ceiling places are going to have good air, but that might not be true. That’s great to hear about your work. I had to take a kid to the doctor last week, and I just kept hoping that that little room had decent ventilation.

[wathe]

19 minutes ago, KSera said:

Wow. That’s really high. Were the ceilings as high as typical gym ceilings? Or were they lower than that? We tend to think that high ceiling places are going to have good air, but that might not be true. That’s great to hear about your work. I had to take a kid to the doctor last week, and I just kept hoping that that little room had decent ventilation.

The ceilings were plenty high - higher than most high school gyms I've been to.

ETA that my biggest personal lesson is that large space =/= well-ventilated space

 

Edited March 27, 2022 by wathe

[wathe]

bump for update

[KSera]

On 12/18/2021 at 7:25 PM, wathe said:

This is a giant, modern athletic facility with 4 ice rinks, multiple gyms and an enormous field house.  All of these areas were set up for volleyball.  Busy with people, but did not appear to be at capacity - plenty of empty bleacher space.  Obvious mechanical ventilation (visible ducts and vents), which seemed to be turned on (could near humming/ventilation noises first thing in the am when the place was quiet).  CO2 peaked in the field house at 3006ppm.  And I was seated right next to an emergency exit door that had an obvious draft - so probably actually worse than that.

Yikes! This just drives home to me that it should be required for facilities to display air quality readings prominently. How else are people to know and make decisions? Monitoring devices are too expensive for everybody to have one to carry around. And if they have to display their readings, they will be motivated to improve ventilation. Unfortunately, I don’t feel like there’s the will to do anything like that right now 😞. 

[mommyoffive]

Wow, your updates are so awesome!!  Thank you.  I love the idea of places showing their air quality.  Man just thinking about it you feel safe in the big ice rinks or sports centers.  They are huge.  So much air in there, you have to be safe.  Now I am rethinking joining those lessons that take place in those kinds of places.  Ack.   My kids dance in a place like that.  Parents are not allowed in, so I can't measure anything.  Ugh.

You or your son haven't gotten sick at all?  

I wonder if personal air purifiers would be useful?

Like this

Amazon.com: Pure Enrichment PureZone Mini Portable Air Purifier - True HEPA Filter Cleans Air, Helps Alleviate Allergies, Eliminates Smoke & More — Ideal for Traveling, Home, and Office Use (Blue): Home & Kitchen

 

https://www.amazon.com/Portable-Purifier-Purifiers-Electricity-Rechargeable/dp/B093PRTWWR/ref=sr_1_5?crid=F2RL7FIUFFLS&keywords=personal+air+purifier&qid=1650652145&sprefix=personal+air%2Caps%2C190&sr=8-5

[wathe]

10 minutes ago, mommyoffive said:

 

You or your son haven't gotten sick at all?  

 

Not yet. We all wear n95 and are maximally vaccinated. Though with current high community transmission, and mask mandates having been dropped a month ago, it's only a matter of time.  

I have been known to sneak my monitor into my kid's gym bag for no-parents-allowed events.

[Catwoman]

I would like to get one of those monitors.

Are they something I can order on Amazon? Does anyone know what brands are supposed to be the best?

[Arcadia]

2 minutes ago, Catwoman said:

I would like to get one of those monitors.

Are they something I can order on Amazon? Does anyone know what brands are supposed to be the best?

The model in OP’s photo, $249 at Amazon.

https://www.amazon.com/Aranet4-Home-Temperature-Ink-Configuration/dp/B07YY7BH2W/

[wathe]

8 hours ago, Catwoman said:

I would like to get one of those monitors.

Are they something I can order on Amazon? Does anyone know what brands are supposed to be the best?

Mine is the Aranet4 Home. (It looks like the price from the manufacturer's website is the same as Amazon). I really like it.  It's synchronized with my phone, which allows me to graph data in real time.  I can also push data from my phone to my laptop into an Excel spreadsheet.  

It's not waterproof or shock proof, so I made a little case for it out of a small plastic snack storage container and some high density foam.  Drilled a few holes in the case at the location of the sensors.   It gets tossed into bags etc in its case, and has been dropped several times without issue.

[wathe]

Bump for camping update first post.

 

[KSera]

I appreciate the pit privy numbers especially; I've been preferencing outhouse scenarios over indoor flush toilets if I have to use a bathroom  while traveling as it has seemed like there would be more ventilation and no aersolizing with the flush. Good to see some actual numbers though.

[Ausmumof3]

Wow, who would have thought a tent would get that bad? That said, they are designed to retain warmth so I guess they also keep in warmed air 

[wathe]

10 hours ago, Ausmumof3 said:

Wow, who would have thought a tent would get that bad? That said, they are designed to retain warmth so I guess they also keep in warmed air 

I know, right?  I was so, so surprised.  The tent has giant windows and the roof of the tent body is 3/4 mesh. As tents go, it's super well-ventilated.  I can only imagine how bad a small backpacking tent with full fly would get!

[wathe]

bump for update

 

[KSera]

I had to go to the dentist last week, and had some very unreassuring readings--it hovered 1200-1400ppm. Mask usage by staff was very loose as well. I kept hoping maybe they have good HEPA filters in the ducts, and it really was just CO2 that was high. They are no longer running air cleaners in each treatment cubicle like they used to.

I had great readings when I had some specialty care at a hopsital last week though--545ppm in a small enclosed room with one other person. That makes me feel much better about getting caught up on all my medical care there.

[wathe]

30 minutes ago, KSera said:

I had to go to the dentist last week, and had some very unreassuring readings--it hovered 1200-1400ppm. Mask usage by staff was very loose as well. I kept hoping maybe they have good HEPA filters in the ducts, and it really was just CO2 that was high. They are no longer running air cleaners in each treatment cubicle like they used to.

I had great readings when I had some specialty care at a hopsital last week though--545ppm in a small enclosed room with one other person. That makes me feel much better about getting caught up on all my medical care there.

The air at the hospital I work at is fabulous.  Never gets above 550 ppm.  This seems to be true for most hospitals around here (lots have citizen CO2 data posted on Raven Clean Air Map). Dentist offices, not so much.   I think the facility standards for hospitals are quite strict.

[fraidycat]

I love reading your updates and observations. Thank you for continuing to share.

[Janeway]

That is very cool! Now I kind of want one of those too.

[happi duck]

I start back teaching at my church so I'm buying one to keep my classroom well ventilated 🤞 I plan to have windows open and am requiring masks.  If the readings are high despite windows we'll find another spot to meet.

I plan to take readings for places I have choices for like shopping at the store with the best ventilation.

I don't want to leave my dentist but I think she'd be open to doing something if I got high readings there.

Thanks again for this thread!