CO2 indoor

[HornetMaX]

Hi all,

I usually train (RowErg and SkiErg) in my garage (5x5.5m, with height 3.5m).

In summer I partially open the front door (tilt-up) and open the two small windows (opposite wall) to ensure some fresh air can come in, usually complemented by a wahoo kickr fan pointing at me.
But in winter, the garage (who is not well isolated, roof is simple tiles with some styrofoam boards right under the tiles) can get cold and I've trained occasionally with door and windows closed (fan off, or on but not pointing at me).

Wondering if working indoor with closed door and windows could lead to CO2 build-up I decided to invest in a CO2 monitor.
The Aranet 4 seems to be the golden standard (for consumer market) but it's a bit pricey, so I went for a Qingping thing (for a fraction of the price) that also has a temperature and humidity sensor (and time). According to reviews, it has as-good CO2 measure accuracy (they use the same NDIR sensor) and main features (app, battery life etc etc).

After calibrating it (manual calibration, 5min outdoor), I did 4 experiments (4 different days):

1. 10' SkiErg + 4x(15'+4R)' RowErg, garage door closed, windows closed, no fan.
   CO2 ppm started at 400 (usual outdoor level), climbed to 500 by mere presence in the garage. At the end of the session it was at 1500 (and it took 1h to drop back to 500).
2. 10' SkiErg + 3x(20'+2R)' RowErg, garage door closed, windows closed, fan ON.
   Started at 420, peak at 2182 after session end. Drop to 500 in 3h.
3. 30' SkiErg + 30' SkiErg + 30' RowErg, garage door half open, windows open, fan ON.
   Started at 420, didn't exceed 535 during the whole session.
4. 10' SkiErg + 2x(10'+4R)' RowErg, garage door half open, windows open, no fan.
   Started at 440, didn't exceed 700 during the whole session.

Now, apparently CO2 ppm is considered to be good if below 1000 (EU standard for fitness centres even says 750). Above 1000 is bad-ish. 2000 is bad, especially for longer periods.

I'm not very concerned by the impact of CO2 levels on my performance (I'm a recreational rower ), but ... yeah, I guess I'll keep door and windows open. Always.

[hikeplusrow]

This is really interesting, and something I'd never considered. I have my RowErg set up in the garage and it's currently very, very cold - no fan on, and small window closed. It's pretty draughty which helps with the CO2, I suppose. During the summer, I have a fan on full blast and the widow open. I don't open the side door or the up and over, as I can cope with both interval training and wasps!

[hikeplusrow]

This is really interesting, and something I'd never considered. I have my RowErg set up in the garage and it's currently very, very cold - no fan on, and small window closed. It's pretty draughty which helps with the CO2, I suppose. During the summer, I have a fan on full blast and the widow open. I don't open the side door or the up and over, as I can cope with both interval training and wasps!

window

[JaapvanE]

so I went for a Qingping thing (for a fraction of the price) that also has a temperature and humidity sensor (and time). According to reviews, it has as-good CO2 measure accuracy (they use the same NDIR sensor) and main features (app, battery life etc etc).

Bought the same sensor about 6 months ago.

Now, apparently CO2 ppm is considered to be good if below 1000 (EU standard for fitness centres even says 750). Above 1000 is bad-ish. 2000 is bad, especially for longer periods.

I'm not very concerned by the impact of CO2 levels on my performance (I'm a recreational rower ), but ... yeah, I guess I'll keep door and windows open. Always.

I have a Wahoo Headwind and a small Honeywell fan pointed at me, and a large (Velux) window directly next to me. Even now, mid-winter with snow outside and freezing temperatures, I use both fans and open the window to the max for both cooling and new O2. When I don't open the window, O2 level spikes above 1500. When I open the window and use the fans, it stays around 850ppm.

So for me, it is fans and window open as far as rain/snow permits.

[JaapvanE]

I don't open the side door or the up and over, as I can cope with both interval training and wasps!

In summer, I open the windows on the other side of the attick as well, creating maximum air displacement, and I use both fans set to the maximum (with the headwind, that is a lot of air being moved). And I train early in the morning or late at night, to avoid the heat and wasps.

[aussie nick]

Hi all,

I usually train (RowErg and SkiErg) in my garage (5x5.5m, with height 3.5m).

In summer I partially open the front door (tilt-up) and open the two small windows (opposite wall) to ensure some fresh air can come in, usually complemented by a wahoo kickr fan pointing at me.
But in winter, the garage (who is not well isolated, roof is simple tiles with some styrofoam boards right under the tiles) can get cold and I've trained occasionally with door and windows closed (fan off, or on but not pointing at me).

Wondering if working indoor with closed door and windows could lead to CO2 build-up I decided to invest in a CO2 monitor.
The Aranet 4 seems to be the golden standard (for consumer market) but it's a bit pricey, so I went for a Qingping thing (for a fraction of the price) that also has a temperature and humidity sensor (and time). According to reviews, it has as-good CO2 measure accuracy (they use the same NDIR sensor) and main features (app, battery life etc etc).

After calibrating it (manual calibration, 5min outdoor), I did 4 experiments (4 different days):

1. 10' SkiErg + 4x(15'+4R)' RowErg, garage door closed, windows closed, no fan.
   CO2 ppm started at 400 (usual outdoor level), climbed to 500 by mere presence in the garage. At the end of the session it was at 1500 (and it took 1h to drop back to 500).
2. 10' SkiErg + 3x(20'+2R)' RowErg, garage door closed, windows closed, fan ON.
   Started at 420, peak at 2182 after session end. Drop to 500 in 3h.
3. 30' SkiErg + 30' SkiErg + 30' RowErg, garage door half open, windows open, fan ON.
   Started at 420, didn't exceed 535 during the whole session.
4. 10' SkiErg + 2x(10'+4R)' RowErg, garage door half open, windows open, no fan.
   Started at 440, didn't exceed 700 during the whole session.

Now, apparently CO2 ppm is considered to be good if below 1000 (EU standard for fitness centres even says 750). Above 1000 is bad-ish. 2000 is bad, especially for longer periods.

I'm not very concerned by the impact of CO2 levels on my performance (I'm a recreational rower ), but ... yeah, I guess I'll keep door and windows open. Always.

I've never considered this at all. When you say 'bad', what does that entail for health and performance?

[p_b82]

Wow - useful to know some numbers there - my room where my erg is located is smaller - and I def would say that things get tougher in winter when I don't open the windows in the room on the longer sessions; never really considered the Co2 amounts as being one of the main factors.... guess I'll be getting the house colder and opening the windows while I'm rowing!

[HornetMaX]

I've never considered this at all. When you say 'bad', what does that entail for health and performance?

There seems to be consensus on the impact of co2 levels on cognitive performance (e.g. school, office work), mild (but noticeable) past 1000 ppm and big past 2000ppm (where other symptoms appear too like drowsiness, mild headache, ...).

On physical performance there seems to be less info: some of it just says "It doesn't matter, totally marginal", some says "use a fan and open the window, always".

I've seen nothing on long term health impact.

Regulations exist and are pretty tight but that may also be due to the fact that proper ventilation also has other effects than co2 concentration: dilution of other pollutants or, more important, increased chances of airborne infections like covid and flu.

Body smell a factor too in a gym

[hikeplusrow]

I'll be looking for a new house soon, and my thoughts on this were already dominated by 'Where will I put the erg'. They'll now be dominated by 'Where will I put the erg for minimal C02 impact'

[JaapvanE]

On physical performance there seems to be less info: some of it just says "It doesn't matter, totally marginal", some says "use a fan and open the window, always".

As I see it, a large part of rowing performance is dominated by the capability of O2 uptake. If O2 uptake is reduced, the anearobic energy system tends to take over, fatigue sets in, etc.. So, an increased CO2 level tends to imply a reduced O2 level, which might hinder O2 uptake.

And to be honest, the open windiw helps get rid of excess heat as well. I hate the first ten seconds in a rowing session due to the cold, love every minute after as I can really get rid of the heat....

[Rowan McSheen]

Never mind any impact on cognitive performance ... your houseplants will be happy.

[Yankeerunner]

I've never considered this, but have noted that most years I go into a slump around mid-January and now wonder if it could be the buildup of CO2 in a tightly buttoned-up house. I've also noted that sometimes after I've had to go outside for a while to shovel snow I have a more lively erg session and always wondered why.

I've ordered a monitor on eBay.

[jcross485]

Very similarly to others here, I've never really thought about this but it makes a lot of sense. I row in my garage almost exclusively (every once in a while I will move it to the backyard and row outside) and the majority of the time I row with the garage door open so I'm getting plenty of air flow. I have noticed quite a bit of difference in running though when it comes to running on a treadmill in a very small hotel gym vs. a large gym vs. running outside; I always chalked it up to differences in treadmills but CO2 can certainly be a contributing factor.

[HornetMaX]

On physical performance there seems to be less info: some of it just says "It doesn't matter, totally marginal", some says "use a fan and open the window, always".

As I see it, a large part of rowing performance is dominated by the capability of O2 uptake. If O2 uptake is reduced, the anearobic energy system tends to take over, fatigue sets in, etc.. So, an increased CO2 level tends to imply a reduced O2 level, which might hinder O2 uptake.

That seems not to be a factor: CO2 ppm is tiny compared to O2 ppm in air, so CO2 doubling or more has a very marginal effect on O2 ppm.

But yeah, there are some concerns emerging: as said, cognitive performance seems impacted (to the point NASA did studies concerning the impact on the ISS crew, where CO2 is on the high side).
A Guardian article mentions a growing body of researcher concerned by potential long term effect of med/long term exposure to med/high CO2 concentrations.

I've ordered a monitor on eBay.

Advice (maybe too late): really cheap ones are sort of useless as they have cheap sensors and they do automatic calibration (only, meaning no manual calibration possible). You want one with an NDIR sensor (a good NDIR sensor, if possible to know) and manual calibration. Everything else is secondary (e.g. battery life, app, data logging etc) but may still be important depending on your usage.

[JaapvanE]

On physical performance there seems to be less info: some of it just says "It doesn't matter, totally marginal", some says "use a fan and open the window, always".

As I see it, a large part of rowing performance is dominated by the capability of O2 uptake. If O2 uptake is reduced, the anearobic energy system tends to take over, fatigue sets in, etc.. So, an increased CO2 level tends to imply a reduced O2 level, which might hinder O2 uptake.

That seems not to be a factor: CO2 ppm is tiny compared to O2 ppm in air, so CO2 doubling or more has a very marginal effect on O2 ppm.

That actually is a very valid and good point.