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Most of us are underestimating the importance of the Hepa Air Filtration System

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Good discussion. The significant pollution (highest levels) comes out of the tailpipe of the car in front of you. Best to avoid "smokers" and diesel trucks. Stay well back of ICE cars at stops or pull into an empty lane if available. Distance from exhaust gas (dilution) is your friend. Better yet, if you can, pull in behind a BEV at stops (don't we wish). Doc Toxics.
 
I was trying to accomplish two things in my OP.
1. To call peoples attention to the potential heath benefits of the MX Hepa Air Filtration System.

2. If you think that $4,500 is too much to pay, explain this to your DS. I hope that Tesla will decide to make their Hepa Air Filtration System standard equipment on all of their cars. It is more than a comfort feature. IMO it is a safety system like air bags and seat belts. The system has three components, the ducts, one or more fans, and the filter elements. The ducts in the MX are probably standard. It's possible that this system uses a more powerful fan, or an auxiliary fan. The fans and filter elements probably cost Tesla under $200. I believe that if Elon understood the potential health implications he will want to include this in the base price of the car, possibly adding $200-$300 to cover their costs.

In any case I hope we can afford a CPO MS, and if Tesla doesn't provide a retrofit kit I will try to build our own.
 
Thank you for the input of Daily Mail Online, this is an interesting report but in this piece of news there are many critical details missing to fully assess. For example, only 5 persons over a week is statistically insignificant. Also it is not mentioned whether the windows are closed all the time. I would need to see the original study before making any conclusions, as media more often than not exaggerates, sometimes even twists, the findings of scientists.

And for the other pdf, HEPA can't help with the benzene, VOCs, CO, NOx, etc. at all. These are gas molecules that no filters on earth can help you with. As HEPA stands for "high efficiency particulate air", it can only prevent people being exposed to particulates. Looking into the pdf file in the link, the studies it cited showed no significant difference between the cabin and ambient air while the other pollutants are higher in the car. My guess is that those cars made in the 90s or earlier have filters that can get rid a lot of the particulate matters.

And finally, even if the air in the car is worse than outside the car, for non professional drivers, the time spent inside the car is still far less than time spent elsewhere. Exposure is not just the concentration of a certain pollutant, it is also the duration. That's why NIOSH and other organizations usually have a short term limit of chemical concentrations and a long term limit, the short term is usually several times higher than the long term.

According to the authors of these studies you are incorrect. Air quality inside cars is much worse, and the authors believe it is a serious problem.:
Why you could suffer from more pollution while driving a car than walking on the streetÂ* | Daily Mail Online

Immediate effects.

Some images below from this pdf:
http://www.pureti.com/content/documents/ICTA-In-Car-Air-Pollution-Report.pdf
View attachment 104583
Since I can't put it in bold I'll call everyone's attention to the last paragraph above.
View attachment 104584
And the section starting with "Similarly"..."elevated levels of auto exhaust" above.
View attachment 104585
 
Good discussion. The significant pollution (highest levels) comes out of the tailpipe of the car in front of you. Best to avoid "smokers" and diesel trucks. Stay well back of ICE cars at stops or pull into an empty lane if available. Distance from exhaust gas (dilution) is your friend. Better yet, if you can, pull in behind a BEV at stops (don't we wish). Doc Toxics.

And TDIs...
 
HEPA can't help with the benzene, VOCs, CO, NOx, etc. at all. These are gas molecules that no filters on earth can help you with.

Doesn't mesh with what Elon said in the introduction.

paraphrased it was three layers of activated carbon that specialize in removing hydrocarbons, acidic gases (like sulfur) and alkaline gases (like ammonia).

are you saying NOx and friends aren't hydrocarbons, aren't acidic, and aren't basic?
 
Sorry I wasn't aware of the activated carbon. Thought it's just HEPA filter. Yes activated carbon is effective for these gas molecules. Not sure how often you need to change them, as they tend to lose effectiveness quite fast though, depending on the environment they are exposed to.

And just for the record, activated carbon is not effective against CO.

Doesn't mesh with what Elon said in the introduction.

paraphrased it was three layers of activated carbon that specialize in removing hydrocarbons, acidic gases (like sulfur) and alkaline gases (like ammonia).

are you saying NOx and friends aren't hydrocarbons, aren't acidic, and aren't basic?
 
Sorry I wasn't aware of the activated carbon. Thought it's just HEPA filter. Yes activated carbon is effective for these gas molecules. Not sure how often you need to change them, as they tend to lose effectiveness quite fast though, depending on the environment they are exposed to.

And just for the record, activated carbon is not effective against CO.

The IQ Air GC AM filter (example filters ammonia) requires four big cartridges about twice a year**, if the fan speed is medium, at $375 per set (other kinds of gas filtration can be as low as $275). There is no way that the Tesla would have this level of filtering unless the change interval is weekly.

** The site says 12-30 months. That would only be the case if you ran the system for a couple of hours every day.
 
The IQ Air GC AM filter (example filters ammonia) requires four big cartridges about twice a year**, if the fan speed is medium, at $375 per set (other kinds of gas filtration can be as low as $275). There is no way that the Tesla would have this level of filtering unless the change interval is weekly.

** The site says 12-30 months. That would only be the case if you ran the system for a couple of hours every day.

So, oversized HEPA filter for full time use and smaller activated carbon filter for bioweapon defense mode only?
 
So, oversized HEPA filter for full time use and smaller activated carbon filter for bioweapon defense mode only?

I guess, but I think you'd need a lot of carbon to do any significant amount of gas absorption. The four IQ filters have about 5.5 kg of carbon and don't last all that long (they do work well while they last). I can't imagine that Tesla's filter has anywhere near that amount.
 
According to the presentation, biodefense mode is creating a positive air pressure in the cabin relative to the outside, therefore preventing stuff from the outside getting in through airflow. Doubt this can affect whether the activated carbon can be used or not. And as soon as activated carbon is exposed to air, it is being used, it's more of a passive method to eliminate unwanted substances. I'm not confident the Model X can make the activated carbon switch between air-tight sealed and exposed to air by user's command.

So, oversized HEPA filter for full time use and smaller activated carbon filter for bioweapon defense mode only?
 
According to the presentation, biodefense mode is creating a positive air pressure in the cabin relative to the outside, therefore preventing stuff from the outside getting in through airflow.

I've heard this a couple of times. Just curious how this occurs without either bringing in outside air or using compressed air. If the former, it seems all of the outside air that's being forced into the cabin to create the pressure must be preprocessed through the carbon and HEPA filters.
 
Not sure how it works in details either. You gotta have outside air coming inside otherwise the passengers will suffocate eventually.

I've heard this a couple of times. Just curious how this occurs without either bringing in outside air or using compressed air. If the former, it seems all of the outside air that's being forced into the cabin to create the pressure must be preprocessed through the carbon and HEPA filters.
 
Not sure how it works in details either. You gotta have outside air coming inside otherwise the passengers will suffocate eventually.

Positive pressure just means more are is coming in than going out. You do that by increasing the intake fans for the HVAC system to a point that the air can't escape the car as fast as you are pulling it in.

It's not rocket science. Just seal the doors/windows as best you can and pump air into the car as fast as it takes to create positive pressure.

In bioweapon defense mode all the incoming air will come through the filters and exit everywhere it can (you can't stop it from exiting, there will be leaks).

It is possible that the pressure differential will keep air from entering somewhere else (an entrance becomes an exit while that mode is on) either by design or by chance. The whole point of the mode is to have the pressure higher inside the car so that any unexpected/unplanned/undetected leaks/gaps/holes are used as exits and not entrances.

The only question I have about bioweapon defense mode is how noisy will the fans be in that mode and how much will the pressure raise in a best sealed case?

I don't really care about the positive pressure mode for my use, I just want better all the time cabin air filtering and I want it on every car I own.
 
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Positive pressure just means more are is coming in than going out. You do that by increasing the intake fans for the HVAC system to a point that the air can't escape the car as fast as you are pulling it in.

It's not rocket science. Just seal the doors/windows as best you can and pump air into the car as fast as it takes to create positive pressure.

In bioweapon defense mode all the incoming air will come through the filters and exit everywhere it can (you can't stop it from exiting, there will be leaks).

It is possible that the pressure differential will keep air from entering somewhere else (an entrance becomes an exit while that mode is on) either by design or by chance. The whole point of the mode is to have the pressure higher inside the car so that any unexpected/unplanned/undetected leaks/gaps/holes are used as exits and not entrances.

The only question I have about bioweapon defense mode is how noisy will the fans be in that mode and how much will the pressure raise in a best sealed case?

I don't really care about the positive pressure mode for my use, I just want better all the time cabin air filtering and I want it on every car I own.
Another question would be, How much energy does it use?
 
Another question would be, How much energy does it use?

Less than running the heat or AC. Fans are insanely efficient, it's just another DC motor on a smaller scale but similar to what drives the car down the road. In fact because it only has to work 99% of the time at a narrow RPM range it will be more efficient than the big motors that have to work at variable RPMs.
 
Less than running the heat or AC. Fans are insanely efficient, it's just another DC motor on a smaller scale but similar to what drives the car down the road. In fact because it only has to work 99% of the time at a narrow RPM range it will be more efficient than the big motors that have to work at variable RPMs.
Thanks. I guess I was thinking about the high energy consumption for heating the cabin and mistakenly thought it was the fans consuming all that energy. Now I recall it's more the heating element since there's no ICE to borrow heat from.