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

[wathe]

1 minute ago, happi duck said:

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!

It is actually very empowering!  Particularly for spaces where you have some control over what you do with the data - either open windows/fix ventilation, or simply choose to leave the space.  

Maybe consider posting your readings on Raven Clean Air Map, so that others can use your data to guide their own decision-making.

[happi duck]

Just now, wathe said:

It is actually very empowering!  Particularly for spaces where you have some control over what you do with the data - either open windows/fix ventilation, or simply choose to leave the space.  

Maybe consider posting your readings on Raven Clean Air Map, so that others can use your data to guide their own decision-making.

Thanks for the reminder!  I do want to contribute my readings!

I will never cease to be stunned that ventilation is not something we have all learned about.  As a society we have had to learn about and adjust to all sorts of new things

[kbutton]

Some of the types of spaces in which you've seen poor air quality are the types of places I've felt lousy in over the years. I have suspected for a number of years now that I am super sensitive to "used up" air (sports places are bad!). I would love to see what our local Lowe's reads at and pretty much any Kohl's I've ever been in. I remember a few longer than normal church activities where sanctuary doors were closed for long periods, and the sanctuary was crowded--I felt like I was going to pass out, and I had extreme air hunger. It was awful. 

 

[KSera]

5 minutes ago, happi duck said:

Thanks for the reminder!  I do want to contribute my readings!

I will never cease to be stunned that ventilation is not something we have all learned about.  As a society we have had to learn about and adjust to all sorts of new things

My dentist office had windows all along the side of the treatment rooms that could’ve been slid open, but they were all closed. I wondered if there might be good reasons in a dental office to keep them closed. And I also didn’t feel in a good position to say anything that might come across as negative about the office right before having sensitive work done 😬. 

[wathe]

1 minute ago, KSera said:

My dentist office had windows all along the side of the treatment rooms that could’ve been slid open, but they were all closed. I wondered if there might be good reasons in a dental office to keep them closed. And I also didn’t feel in a good position to say anything that might come across as negative about the office right before having sensitive work done 😬. 

Right.  It's actually tricky to give this kind of feedback to a place like a dentist office (or any other private business where you are a customer) - "by the way, your air quality is really bad, I've checked!"  Odds are that the staff will have no idea what you are talking about, and also won't really care.

A quick google shows me that ASHRAE has a detailed technical webpage on COVID and air-quality in dental facilities.  Interesting reading.

[Harriet Vane]

Thanks for your updates. 😊

[wathe]

 

For those looking for monitors:

I've seen Vitalight monitors for sale for as little as $60 on amazon.  DonateMask.ca carries them too, with free shipping to Canada, US and Europe.  Rechargeable with 8h battery life, and I don't think that they can record data or sync with phone, but the price sure is good.

Canadian peeps:  Canadian Tire is carrying Aranet4 CO2 monitors.  My local store had some in stock.  Much more expensive than Vitalight, but syncs with phone to graph data, stores up to 2 weeks of data, can push out data files into Excel, battery life is very long (still using the very same AAAs since Christmas).  I bought mine from ES-Canada (way back when they were the only business that I could find in the country that sold them).

 

[wathe]

Bump for update in first post

[mommyoffive]

Wow, that is so not what I would think.  The school compared to the tent.  Is the school masking at all? 

[happi duck]

I just set up my aranet4!

Does it have an on/off switch or does it just stay on?

Am I understanding: green is great and yellow is average?  Passable? 

I'll be at my church Saturday helping with a concert and then on Sunday teaching a class.  I think it will help a lot to know the ventilation status!

[wathe]

1 hour ago, mommyoffive said:

Wow, that is so not what I would think.  The school compared to the tent.  Is the school masking at all? 

Masking is not required.  Maybe 5% masking.

[wathe]

14 minutes ago, happi duck said:

I just set up my aranet4!

Does it have an on/off switch or does it just stay on?

Am I understanding: green is great and yellow is average?  Passable? 

I'll be at my church Saturday helping with a concert and then on Sunday teaching a class.  I think it will help a lot to know the ventilation status!

It stays on all the time.  The batteries last a long time. Mine has been on continuously since Dec 2021, and the original batteries are still going strong; they're at about 60% life remaining (judging by the little battery icon). I usually have it set to take a reading every 2 minutes.

Green is < 800, which is good by most standards.  Yellow is 800-999, passable but not great.  Red is 1000 or greater, not good.  "Standards" vary from place to place

It is not shock-proof, so don't drop it.  I made mine a little case out of a plastic snack container (with holes drilled near the sampling ports), foam, and bubble wrap.

[wathe]

@happi duck

Edited September 8, 2022 by wathe

[happi duck]

Welp.  During errands a couple stores were green, yay!  A store I thought would be great was yellow.

With windows open my house was green, yay!

With the air conditioning on and windows closed my house is red!  Yipes!!

On one hand I'm glad to know but on the other hand I'm really overwhelmed to figure out how to fix this!

I hope my classroom on Sunday isn't terrible 

[Harriet Vane]

Thanks for your continued updates, Wathe.

[wathe]

13 hours ago, happi duck said:

Welp.  During errands a couple stores were green, yay!  A store I thought would be great was yellow.

With windows open my house was green, yay!

With the air conditioning on and windows closed my house is red!  Yipes!!

On one hand I'm glad to know but on the other hand I'm really overwhelmed to figure out how to fix this!

I hope my classroom on Sunday isn't terrible 

 

How high is you reading at home?  The problem with "red" is that 1000 1500 is very different, risk-wise, than, say, 5000 - but both are red.

Most Canadian homes that I've visited with my monitor in winter hover around 1000ppm when occupied with people all in the same room.  My home is the same.  That's pretty normal for private, domestic indoor air, I think.

Of course, with respect to covid transmission,  ventilation matters most in places where you are sharing air with lots of people.  My CO2 value of >2000 in my solo tent was meaningless for covid risk in that specific instance, because I can't catch covid from myself.  But would be meaningful if I were sharing a tent with people outside my family bubble, and  very meaningful in an airplane during boarding with no air circulating though the HEPA, or other very crowded venue.

The colour system cut-offs are somewhat arbitrary, as well.  Some jurisdictions use a cut-off off 1500 instead of 1000. 1400

The industrial standard for C02 itself (regarding CO2 toxicity) here is, IIRC, 5000ppm for sustained exposure and 30 000ppm for short exposure.  So how far into the red you are matters.

I'm not worried about CO2 of hovering around 1000ppm at home.  I mean, obviously lower is better, but I'm not going to gut or replace my entire ventilation system over it.  Instead, we crack windows intermittently when it's just us at home, and we crack windows continuously and run the CR box whenever we have people in the house who don't live here.

We have a heat-recovery ventilator, which we run all year. They're common here (standard with new construction, I think), and primarily meant to help manage humidity in winter in houses that are well-insulated/tight.   It helps tremendously.  But it's not nearly as effective as open windows.  We still get readings in hovering around 1000 with it running.

The easiest thing to do to reduce airborne infectious disease risk might be to run filtration (HEPA or CR box) and crack windows intermittently.  Way cheaper than fixing ventilation.

ETA  - I realize that I've conflated the Aranet red cut-off of 1400 with the Raven Clean air app cut-off of 1000.  (A real-world example of arbitrariness....)

Edited September 9, 2022 by wathe

[happi duck]

@wathe Thanks for the information!

I didn't know that a gas stove and oven can raise levels.  We were using both while the windows were closed and it went up past 2000.  Even with opening windows it took time to come down.

We actually need a new stove so might go electric!

[wathe]

bump for update in first post

 

[fraidycat]

59 minutes ago, wathe said:

bump for update in first post

 

I really appreciate your updates, thank you for sharing.

[Arcadia]

We actually wind down the windows on freeways if traffic is not heavy. I feel nauseous when the air inside the car feels stuffy. Also we have to change the cabin air filter often, which is rather easy to do.  

[wathe]

Bump for update in first post.

Also, we bought a Vitalight for DS to take to school.  (He uses it to evaluate where to each lunch indoors in bad weather).  We've had it about two months.

It's pretty good.  Within +/- 50ppm of my Aranet if we keep it calibrated.  We've discovered that it needs calibrating about once a week or so, or it gets wildly inaccurate.  Calibrating is technically simple:  a few button pushes then a couple of minutes in outdoor air.   (Less practical in the winter, because it doesn't like temps below 0 Celcius, so I have to choose my weather window, and put it in my coat pocket to keep it from freezing).  

It's advertised battery life (rechargeable) is 8h, but it actually runs much longer on a single charge, more like 24+h before it poops out.  That was a pleasant surprise.

Well worth $60.

[mommyoffive]

6 minutes ago, wathe said:

Bump for update in first post.

Also, we bought a Vitalight for DS to take to school.  (He uses it to evaluate where to each lunch indoors in bad weather).  We've had it about two months.

It's pretty good.  Within +/- 50ppm of my Aranet if we keep it calibrated.  We've discovered that it needs calibrating about once a week or so, or it gets wildly inaccurate.  Calibrating is technically simple:  a few button pushes then a couple of minutes in outdoor air.   (Less practical in the winter, because it doesn't like temps below 0 Celcius, so I have to choose my weather window, and put it in my coat pocket to keep it from freezing).  

It's advertised battery life (rechargeable) is 8h, but it actually runs much longer on a single charge, more like 24+h before it poops out.  That was a pleasant surprise.

Well worth $60.

Is this the same thing?

 

Amazon.com: Vitalight Mini CO2 Detector, Air Quality Monitor, Stylish and Lightweight CO2 Monitor You Can Use Anywhere. White : Industrial & Scientific

[wathe]

Just now, mommyoffive said:

Is this the same thing?

 

Amazon.com: Vitalight Mini CO2 Detector, Air Quality Monitor, Stylish and Lightweight CO2 Monitor You Can Use Anywhere. White : Industrial & Scientific

Yes, that's the one.

[wathe]

My parents also bought a vitalight.

My dad has breakfast with a few buddies at a not-crowded restaurant occasionally.

He showed it to the restaurant staff (who overheard him talking to buddies about it, I think - he wasn't purposely trying to complain or anything) .  Shortly afterward, the numbers at the table improved by quite a lot.  He's pretty sure that him showing  numbers to the staff caused them to turn on or turn up the ventilation system.  If you know better, you can do better etc.

[wathe]

Adding that the vitalight has an annoying alarm when CO2 exceeds 1000ppm.  

It can be turned off.  But it defaults to alarm-on when turning on the unit, so you have to remember to disable the alarm every time you turn the thing on.    It's little bit annoying.  (though, we leave ours on all the time.  The only time I have to turn it on is if I've let the battery run down completey and had to recharge from nothing.  so not terrible either)