CO2 levels in the car

[Linctex]

"Badtlc" is 100% correct.

I've been working in the aerospace industry for decades, and a lot of the spaces people work in are extremely confined.

We use MultiRAE gas monitoring systems. They continuously check for TONS of different things in the air you are breathing. CO2 isn't really a concern - OXYGEN LEVEL IS. CO2 displacing nitrogen isn't as big a concern as displacing oxygen... that's critical.

 

[oil_film_movies]

Reading this article makes me think I need more houseplants inside my house! Right?

What we could have is a Control System. Read O2 or CO2 levels inside the car, then squirt in fresh air when it gets low.

Also, we need a balance, as in the sealed aquariums out there (plants+shrimp).

 

[SHOZ]

Originally Posted By: ARCOgraphite
Originally Posted By: SHOZ
I have an open flame ventless heater I use and that is why I have the CO2 meter.

The drive was over an hour.The CO2 levels went up to the 1300 range within 10 minutes.



I think you are confused, you should be worrying about Carbon MONoxide or CO not carbon dioxide. Safe CO2 threshold level ~ 10,000 PPM is 1 percent which is no effect.

Get a Carbon Monoxide meter if you have a non vented open flame heater! That sounds extremely dangerous.

You don't have a teenage girl texting you telling you to get back in the car, do you?

Be careful out there

- Ken
I am not confused. You should look a the link to the closed thread. Once which I posted..... The original thread https://bobistheoilguy.com/forums/ubbthreads.php/topics/4477940/1



And a vent less open gas flame produces near 0ppm of CO. Look at all the gas stoves and ovens in use. I went through this discussion 4 years ago when I put in the heater. Most said I would be dead by now.

I do have a CO monitor and it has never even peeped in three years.

 

[Tdog02]

You guys should look at indoor air quality tests that were done by NASA. Very interesting and eye opening about the air you breathe. I got several recommended plants that require little to no maintenance to clean the air at home.

As far as the car issue... crack a window and/or pop into fresh air mode every half hour or so. By the way, 20+ years in law enforcement and the problems I have seen with most (almost all) police vehicles have been caused by aftermarket installation of equipment. That may or may not be the case with the explorers but it would be the first place I looked.

 

[brave sir robin]

Its low levels of carbon monoxide that causes problems NOT CO2

ffs just google news search "carbon monoxide" and it brings up the police story yall are talking about

My family moved into a different house right around the time I graduated high school. For a few months everyone in the house was sleeping in an extra hour or two occasionally waking up with headaches. My mom contacted the real estate people and they referred her to some type of inspector and it turmed out the old school stand up gas wall heater was leaking exhaust directly in the house. The carbon monoxide levels were very high. I do not remember the exact amounts but my mom said it was borderline dangerous.

 

[PeterPolyol]

Originally Posted By: SHOZ
Originally Posted By: badtlc
Originally Posted By: SHOZ
As I stated in the other thread 1000ppm is considered OK but at 3000ppm I start to feel discomfort. 4000ppm and I get a headache and breathing discomfort. I have an open flame ventless heater I use and that is why I have the CO2 meter.

The drive was over an hour.The CO2 levels went up to the 1300 range within 10 minutes.

I would assume with two people or more the level would be much higher. Cracking the window with it in recirc mode lowered the CO2 quite a bit, 800ppm range. Switching to fresh air it quickly dropped below 1000ppm.

Please leave politics out of this, though I don't see where politics got brought up in the other thread.



This is about science not politics. Do some basic research. Toxicity levels of CO2 happen around 40,000 ppm. The issues relate to concentrations/pressures in blood vs air. This planet has seen CO2 levels well above 1000ppm before. It is well within human tolerance.

also, in a closed off environment, increases of CO2 means reduction of oxygen. You should be monitoring the oxygen content as that is the driver of your feelings, not CO2 at these levels.
The other thread was closed because of politics. It wasn't me and I don't see any political post. So maybe they were deleted?


Sorry about that fellas/mods. I think it was my post in that thread that prompted the close. I apologize.

 

[oil_film_movies]

Originally Posted By: brave sir robin
Its low levels of carbon monoxide that causes problems NOT CO2

CO exposure is another subject. We're talking about CO2 here, and it is a problem.

 

[Nyogtha]

Check the math on your chart

1% = 10,000 ppm (green on your chart)

As previously mentioned, this is 10 times the 1,000 ppm (0.10%) range under discussion in the linked article

3% = 30,000 ppm (blue on your chart) = 30 times 1,000 ppm

5% = 50,000 ppm (purple on your chart) = 50 times 1,000 ppm

8% = 80,000 ppm (red on your chart) = 80 times 1,000 ppm

 

[oil_film_movies]

Originally Posted By: Nyogtha
Check the math on your chart ... 1% = 10,000 ppm (green on your chart)...As previously mentioned, this is 10 times the 1,000 ppm (0.10%) range under discussion in the linked article

That chart (above) is correct. The 0.10% level (1,000 ppm) you mention is the "comfort level", or when it just starts to get slightly uncomfortable, as the article said.
Normal CO2 levels are 0.04% (400 ppm), so the "comfort" transition occurs at twice that normal level.
Notice 1% CO2 levels (10,000 ppm or about 20 times normal CO2 levels) is when drowsiness is a real problem, bad for driving of course. Could be slightly drowsy at the 7,000 ppm CO2 levels the original article has on its chart.

More medical paper references:

"Its (CO2) main mode of action is as an asphyxiant, although it also exerts toxic effects at cellular level. At low concentrations, gaseous carbon dioxide appears to have little toxicological effect. At higher concentrations it leads to an increased respiratory rate, tachycardia, cardiac arrhythmias and impaired consciousness. Concentrations >10% may cause convulsions, coma and death." -- https://www.ncbi.nlm.nih.gov/pubmed/16499405

"EPA’s short term exposure limit (15 min) of 3% CO2 and a maximum exposure of 4%" -- http://articles.sae.org/15377/

 

[Shannow]

Originally Posted By: SHOZ
Seeing s the other thread has been locked for politics...

Last night went out with my CO2 meter and tested the content in the car while driving with the AC in recirculate.

Base CO2 was 303ppm at the start, peek was around 1500ppm. It was around 1350 for the most part.

This is with one person and a small dog. Car interior volume is 98 cu ft. Add another 10 cubic feet for the trunk. With the CC on fresh air, low fan speed and windows up, the CO was around 550.


Thankyou for going to the effort of doing your testing.

Interesting, and representative of the SAE study.

To the naysayers, it's not about knocking you out senseless, it's about the modern trend for Recirc to virtually totally seal the cabin for economy gains, and the affect on the operators driving long distances to safely and effectively manage throwing a two tonne machine at 70MPH past oncoming traffic.

http://www.hobodataloggers.com.au/Attachment/DownloadFile?downloadId=1903

Quote:
In a groundbreaking controlled study [9], according to the Lawrence Berkeley National Laboratory, “On nine scales of decision-making performance, test subjects showed significant reductions on six of the scales at CO2 levels of 1,000parts per million (ppm) and large reductions on seven of the scales at 2,500 ppm. The most dramatic declines in performance, in which subjects were rated as ‘dysfunctional,’ were for taking initiative and thinking strategically” [10]

 

[ffhdriver]

Remember no car does 100% recirculated air. Fed regulation from years ago unless it's been changed.

 

[Nyogtha]

This is all directionally opposite decades of studies conducted through US and vatious eorld navies, NOAA, NASA, & numerous scuba diving agencies.

Grade E compressed air requires 1000 ppm CO2 maximum and 10 ppm CO maximum.

5 stmospheres absolute is a generally recognized limit for using air as a breathing gas, due to hitting 4 atmospheres absolute partial pressure nitrogen and nitrogen narcosis effects on perception and decision making in an atmosphere that is immediately dangerous to life & health unless one possesses gills (100% aqueous water).

So at 132 feet sea water (50 m fsw), Grade E scuba breating air is equivalent to breathing air with 5,000 ppm CO2 and 50 ppm CO at one atmosphere absolute pressure (surface sea level). CO2 buildup in the bloodstream via hypercapnia from shallow or deliberate skip breathing always can be an issue, and the hypercapnic reflex to breathe is triggered by blood CO2 levels, not blood O2 levels.

Greater depths (partial pressures) are strongly advised to reduce nitrogen content with another diluent gas. Adding helium to dilute nitrogen content and actually reducing oxygen content is a typical next step in reducing partial pressure effects as oxygen toxicity greatly increases above 1.6 atmospheres absolute oxygen partial pressure. Many breathing gas agencies drop the maximum CO2 concentration to 500 ppm and maximum CO concentration to 2 ppm for mixed-gas diving applications for depths greater than 5 atmospheres absolute total pressure (and any depths gases blended by partial pressure method are used at).

USN requirements were 500 ppm max CO2 until 1989, when additional data was available and it was raised to 1000 ppm CO2.

Color me skeptical at best based on many hours behind the wheel in hot climates as well as many hours underwater at elevated pressures (certified to dive to 6 atmospheres absolute pressure / 165 fsw / 60 m fsw and been there), including being tested on time required to add random 6 digit numbers together both at the surface and at depth, that 1000 ppm CO2 at 1 atmosphere absolute pressure is the real culprit in an article which totally neglects corresponding CO concentrations in the vehicle cabin or building. One has to wonder why CO concentration data was not included in these publications the links posted take one to.

 

[Shannow]

Originally Posted By: ffhdriver
Remember no car does 100% recirculated air. Fed regulation from years ago unless it's been changed.


Read the SAE paper linked...
http://articles.sae.org/15377/

Apparently they ARE going to reducing fresh air to zero, in a drive to get another 0.0000000000000000001MPG...

 

[Shannow]

Originally Posted By: Nyogtha
One has to wonder why CO concentration data was not included in these publications the links posted take one to.


One has to wonder why this paragraph in the SAE paper is ignored too...
Quote:
Although he had no specific data, Mathur said that research also needs to consider possible contributions from carbon monoxide (CO). He observed that in recirculation there is no positive pressure in the cabin, so with exhaust and underbody seams leakage, CO can penetrate. The level would be subject to great variability based on the exhaust system and car. If it reaches a level of 30 ppm, it is likely to cause passenger headaches.

 

[Tegger]

Originally Posted By: SHOZ
try and stay on the subject matter of CO2 levels in a car with the reticulation mode on.

OK. Then I will say that the OP sees high levels of CO2 inside his car with the recirc on because of his own breathing.

Ambient air is about 0.04% CO2.
OP's breath will be about 4.0% CO2, or 100 times higher than ambient.

Is that science-y enough?

 

[CR94]

Originally Posted By: Shannow
... Apparently they ARE going to reducing fresh air to zero, in a drive to get another 0.0000000000000000001MPG...
Specifically what manufacturer is going to be that foolish?

 

[Nyogtha]

It was not ignored, poor assumption there mate. CO measurement was clearly neglected, if it was in fact not measured.

One really has to wonder why it was not measured concurrently with CO2, or not reported, therefore coming to the conclusions in the graphs that CO2 is the culprit.

If agencies like OSHA find 1000 ppm CO2 acceptable for Grade D breathing air used by folks in IDLH atmospheres at 1 ATA, especially including emergency responders in stress situations, how is 1000 ppm CO2 such a culprit for other decision making folks not in anywhere near that level of physical activity and stress?

Similarly, up to 0.50 ATA CO2 partial pressure is allowable for scuba divers in an indisputedly IDLH atmosphere with factors including nitrogen narcosis concurrent supporting the decision making.

What have all these other agencies missed over many decades?

And I still see no mention on concurrent CO levels measured or otherwise dismissed in the linked article on indoor air quality (notably not linked by you).

 

[SHOZ]

One thing the recirc is good for in the country is blocking off the smell of a hog farm as you get in the downwind air from it. On both my cars you will not smell anything. I'd say they are near 100% now.

Even in fresh air and no fan there is little air moving through until you turn on the fan.

 

[Shannow]

Originally Posted By: SHOZ
One thing the recirc is good for in the country is blocking off the smell of a hog farm as you get in the downwind air from it. On both my cars you will not smell anything. I'd say they are near 100% now.

Even in fresh air and no fan there is little air moving through until you turn on the fan.


As we came out of elephant butte in 2014, I saw something black and white dead in the middle of the road...put the AC on full open (vent) as we neared it...sure enough, it was a dead skunk...and I was the only occupant expecting it.

gotta get your giggles when you can.

 

[Shannow]

The studies on mental performance are being done sans CO, as the exploration is how people perform in regular environments, like work and school, with modern ventilation systems...NASA and the military have a different agenda, in that they are trying to work out the minimum acceptable (read cost effective) environment for people in extreme and abnormal conditions (spacecraft and submarines).

It would seem a little silly to include CO in a study of how your office workers perform, and how school children learn, wouldn't it ?

Your average worker/student, in the average workday, in the average workplace isn't pushing the extremes of an astronaut or submariner, so subtler effects need to be measured.

The linked SAE paper is building on that to what happens in a "normal" environment that "normal" people work and drive in, yes it is absent CO, but it's still relevent in the stated sphere...ADD Co, and it's obviously worse, eh ???

Here's the study (for normal people, at normal workplaces, at atmospheric pressure).

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3548274/