CO2 sensor recommendation

WARNING: you might wanna stay away from senseair products!

I was referred to one of their videos/promos  as evidence of CO2 toxicity.

It makes a bunch of absurd misleading devious and false claims. For example, it claims that CO2 levels over 0.5% (5000ppm) are deadly to humans at

https://youtu.be/HutR7V0SVn8 &t=2:36

while displaying stock video showing someone suffocating to death.  Not so truthy.

The concentration needs to be about four times as high to cause any detectable affect in humans. (Source, plus Lots more peer-reviewed toxicity info at https://toxnet.nlm.nih.gov/cgi-bin/sis/search/a?dbs+hsdb:@term+@DOCNO+516  )

Hi Matthew,

The example you give doesn't seem to be a reason to 'stay away' from senseair products. If anything, I appreciate that they made this information available to the layman.

mrlvy  wrote:

 

WARNING: you might wanna stay away from senseair products!

I don't get the reason why you're suggesting such a dramatic warning, when we're all used to recognising the difference between infomercials/marketing content and real test reports. Otherwise we couldn't watch TV!

It's not a medical lecture explaining precisely how to measure that value (is the mentioned 0.5% value an average for instance?). That part of the video which I viewed seems to be an attempt at explaining to a non-expert audience the effects of CO2 at certain levels.

The video just mentions that there is a physical response, and that 'about that' people experience suffocation and other effects, eventually leading to faintness and death.

Given it's not a medical video and their audience could well be engineers who want a value to plug into their CO2 alarms, if I was a customer I'd sleep better knowing the alarm was coded to alert at values well below 0.5%, than anywhere near 2%!

Government information may well use such recommendations too - again, because the website audience won't be people looking for raw medical data based on certain human size and so on.

This website gives the same 0.5% value as a 'time weighted average' as a guideline to work to:

https://www.ccohs.ca/oshanswers/chemicals/chem_profiles/carbon_dioxide.html

If a medic used that website for research it would be silly, but for an engineer to use that as a beginning point toward working out thresholds in their CO2 alarm system, doesn't seem unreasonable on the face of it..

Here are the levels an equipment manufacturer suggests.. (source kane.co.uk). It suggests that some physical effects are noticeable at that value (5000ppm) and below, whereas you're suggesting the level needs to be 20,000ppm for any detectable effect:

Hi Matthew,

The example you give doesn't seem to be a reason to 'stay away' from senseair products. If anything, I appreciate that they made this information available to the layman.

mrlvy  wrote:

 

WARNING: you might wanna stay away from senseair products!

I don't get the reason why you're suggesting such a dramatic warning, when we're all used to recognising the difference between infomercials/marketing content and real test reports. Otherwise we couldn't watch TV!

It's not a medical lecture explaining precisely how to measure that value (is the mentioned 0.5% value an average for instance?). That part of the video which I viewed seems to be an attempt at explaining to a non-expert audience the effects of CO2 at certain levels.

The video just mentions that there is a physical response, and that 'about that' people experience suffocation and other effects, eventually leading to faintness and death.

Given it's not a medical video and their audience could well be engineers who want a value to plug into their CO2 alarms, if I was a customer I'd sleep better knowing the alarm was coded to alert at values well below 0.5%, than anywhere near 2%!

Government information may well use such recommendations too - again, because the website audience won't be people looking for raw medical data based on certain human size and so on.

This website gives the same 0.5% value as a 'time weighted average' as a guideline to work to:

https://www.ccohs.ca/oshanswers/chemicals/chem_profiles/carbon_dioxide.html

If a medic used that website for research it would be silly, but for an engineer to use that as a beginning point toward working out thresholds in their CO2 alarm system, doesn't seem unreasonable on the face of it..

Here are the levels an equipment manufacturer suggests.. (source kane.co.uk). It suggests that some physical effects are noticeable at that value (5000ppm) and below, whereas you're suggesting the level needs to be 20,000ppm for any detectable effect:

Hi Shabaz,

Your table is a bit old - the current atmospheric base level is 406ppm:

https://www.co2.earth/daily-co2

The other numbers are broadly correct.

I did find the video totally weird (doom background music, end of the world tone of narration, people captive in jars, etc etc)- so much so that I wondered if it had anything to do with the CO2 sensor company - but it does seem to be from them.

I don't think it will help them sell sensors !

MK

I stand by my statement :

it claims that CO2 levels over 0.5% (5000ppm) are deadly to humans at

https://youtu.be/HutR7V0SVn8 &t=2:36

while displaying stock video showing someone suffocating to death.

You claim that’s not true. But it is true. and anybody can quickly skip to 2:36 to verify that. so your argument fails.  and your credibility takes a nosedive.

I also stand by my other claim-the claim sourced to NIH, though there is less of an overwhelming consensus behind that claim, and I did use the caveat ‘about’. .. because subtle changes are just that. Reasonable people can disagree over whether a subject is clinically depressed but it’s all a lot harder and rarer to find a situation where they disagree over whether the test subject is alive or dead.

You seem to forget: Correlation does not imply causation. Don't conflate the two.

And MK is right; there’s lots more that’s, questionable in the video.

mrlvy  wrote:

 

it claims that CO2 levels over 0.5% (5000ppm) are deadly to humans at

https://youtu.be/HutR7V0SVn8 &t=2:36

 

Well, that's technically true I'm afraid. Levels beyond about 5000 ppm can be deadly.. depends what the narrator meant when he used the word about, and how you measure it surely, and on whom - I sure wouldn't want to test a sustained 5000 ppm on a baby, or where it peaked way beyond that, but the average was 5000 ppm.

You're reading way too much into a marketing video.

The products might or might not be bad, I don't know - but certainly your conclusion "WARNING: you might wanna stay away from senseair products!" makes no sense - no engineer that I know of would use a single marketing video to support that. Have you tested the products to back up your "warning"?