[androdev]

I don't know about my lungs but I do care about keeping the car interiors dust free Happy to know it has good side effects for health as well.

[Kosfactor]

Long time ago my Wife is driving us down to the restaurant one evening with the windows down in our old car, it was a very peaceful and clean part of the city. Some maniac in a motorbike while trying to overtake another vehicle from the opposite side knocked off the driver side mirror at really high speed.

There were tiny shards of glass stuck on her face, her eyes were protected by the sunglasses.

Now the windows are rolled down briefly every morning to make sure the motor works and then rolled up.

[earthian]

Originally Posted by ashis89

When I saw my face in the mirror in his washroom, the area around my eyes were white (protected by the sunglasses) and most of my face was black.

Reminds me of the steam engine trains of some decades back. I used to travel to Chennai annually with my parents during the 60's and naturally i would sit near the window and press my face against the bars in the 1st class compartment ( No AC compartments those days) trying to see ahead or the scenery. After being thus plastered for some time, when i removed my face, it used to have horizontal lines (where the coal +smoke did not permeate due to the bars) across my otherwise totally black face.

[dark.knight]

Again, we live in an era where each and every activity on earth is introspected, and articles are written for the sake of it, preying on the number one fear of the people - sickness.

It's my personal opinion that we steer clear of such deep introspection for our own sake. Yes there is an increased level of ash particles, concrete, fine sand, carbon monoxide, trace amounts of methane etc, largely due to human activity, and that air is the same whether one is walking, riding or driving in an open car, the only difference with exposure during higher speeds is that more volume of the varied VOC particles will enter the system like a forced induction system, specially through the mouth where direct entry to lungs is a given.

I'll say that we should continue to do what we always did in our country, luckily we're blessed with a tropical climate which at no point forces us to always use heating or cooling inside a closed environment. As far as cars go, it's better if I put it across in points :

Risks/disadvantages of open-windows :

- Bad air and VOC will enter the cabin IF the atmosphere is polluted.
- Dust accumulation inside the cabin, seats, carpet etc, a nightmare for asthmatics.
- Higher drag force, since air enters the cabin and gives resistance to motion, resulting in reduced FE and more engine stress.

Risks/disadvantages of closed-windows :

- Always keeping the aircon on, will result in higher carbon monoxide (a deadly gas) concentration levels, it'll result in fatigue, yawning, mood-swings and hallucinations to begin with, worst case scenario, the passengers will meet the creator.

- Legionnaires disease, caused by a bacterial strain called Legionella pneumophila, is a possibility.. it is a pneumonia that is far more deadly than the coronavirus family caused issues. Though this spreads mainly through soil and land, the trace samples were found from every aircon piping in older cars.

- Fungal infestations can also happen in a fully closed loop car ventilation system.

How do we balance?

1) Ensure the car interiors get enough unhindered sunlight (with glasses down) once a week, an hour or so. UV is nature's finest antiviral/antibacterial agent.

2) Clean interiors with proper chemical free, but reasonable cleansing agents, at least once a month, steering wheel, shift lever and touch points more frequently.

3) I ensure that every day, all 4 windows are down for the first 5-7 minutes of travel time, rest the aircon can take over.

4) Windows can be gladly downed away in thinly populated, low traffic areas.

5) Vacuum the interiors (compulsory) every week, i.e seat crevices, floor mats, roof fabric etc. Invest in a small vacuum rather than pay exorbitant prices to detailers, 6-8k range.

There you go, you should have a happy time inside the car with these methods, though I wont dream of exterior treatments, wraps, body polishing etc, the interiors are important to me and should be spotless. Cleaner the car, the more you can use the aircon, if you're using the aircon in a completely closed loop ventilation system with no periodic cleaning, its much more deadly than outside air.

[nitishk]

What the article doesnt mention that it is a safety risk in most of these countries especially India. I had my mobile phone stolen at a traffic signal because I had not rolled up. Its been 15 years and I assure you that I dont drive with windows rolled down. The only time the car gets "fresh air" is when I am cleaning it.

[airbus]

I use to drive with windows rolled up due to multiple factors:

1. Less exposure to pollution (both air and sound)
2. Avoid dusts coming inside the car
3. Safety

In 2009 while driving to Pondicherry, I drove half of the distance by rolling down windows, because of that right had was exposed to sun and had sunburn.

[ruzbehxyz]

I always drive with the AC on in Auto mode at 24 deg.C and windows rolled up no matter what the weather is. Its become a habbit now for me.
On rare occasions, I drive with windows rolled down while off roading, photography etc.

[Amukherjea]

One question do you ever come off the recirc mode? Most European cars the aircon will switch to fresh air mode by default. I don't know about the new Mercs but 2003 2008 models even you put on the recirc it would go back to fresh air after some time.
Same happened in Yeti which I used to drive.
Also if you read the manuals most recommend keeping the fresh air inlet open.

I for one on the highways drive with recirc off. In town in stop and go traffic the recirc is kept on.
Will like some opinions please.

[HTC]

I was a strictly non AC person before. Even in summer used to keep windows open as rolling up all windows used to make me feel clastrophobic. It all changed when me and my buddy did a impulsive drive from Mysore to Goa on a new year eve. It was a night drive and i did the complete driving. With windows rolled down for full journey, once we reached, my throat gave up due to inhaling cold and dusty highway wind. For next 2 days in Goa i was confined to hotel and my friend had to go alone and enjoy the discs and pubs .

After that incident, its always AC ON in city and highways. In forest and clean environments i let fresh air in the car.

[Thermodynamics]

Thanks for the topic. Ever increasing traffic, open incineration of thrash, pulverized sand particles emanating from wet/dry grinding between tyres and tarmac have made driving on our roads quite taxing. Most vulnerable are motorcyclists, auto drivers, traffic police, road side vendors, non-AC buses/TT such as school bus and pedestrians. Many people get eye allergies, dryness, pterygia growth.

Cars are a boon in that sense, they provide a safe filtered chamber, minimizing our exposure to external hazards. Though O2 levels need to be replenished once in a while especially when the car is fully seated.

Many posts have already covered the pros and cons. If I have to add to the list, I would add

Pros
- NVH levels
- Music audio quality/clarity
- Minimizes driving fatigue
- Windshield defogging, especially during the rains

Cons
- Dry air. have a moisturizing lotion handy, or install a cabin moisturizer
- Too cold during the rains. keep a pullover, may be Team-BHP sweat shirt , a light warm shawl for passengers.
- Fuel efficiency. There was a period when AC used to guzzle gas. But today, most modern cars are very efficient that the toll on FE is barely noticeable. However, the scenario might make a comeback with EVs.

[v1p3r]

Originally Posted by GTO

I guess bikers & those who drive open cars (like my Jeep) are even worse off?

What'll really get your goat is seeing how small changes in PM level - a 10 count increase etc. - make a massive difference to life expectancy and disease risk. I haven't rolled my windows down in years in an urban environment.

And then there's this from Harvard, saying that PM increases Covid fatalities.

[GrammarNazi]

Absolutely agree.

I've been wondering if I would again want to travel in city traffic without a face mask, not just Post-COVID, but even in the distant future.

Having experienced low pollution levels during lockdown, city commute without a proper mask just doesn't seem like a sensible thing to do.

I'm sure someone would soon come along with stats showing pollution within confined areas of homes and offices is more than in the open air, but what those numbers really won't say is that they've been measured in large open areas with "ideal" traffic compared to the often realistic scenario wherein there's crazy heavy traffic.

None of that would matter. IMO Masks are here to stay.

[vharihar]

I also prefer recirculation mode with AC on with windows closed, for reasons outlined by forumers here.

Question:
In recirculation mode, is it *literally* as the name implies, ie. The same air is recirculated all the time? Or is the AC system smart enough to take in some fresh oxygen *every once in a while* so as not to get saturated with CO2 in the cabin?

What kind of filters are there and what do they do? And when do they kick in, in fresh mode or in recirculation mode?

[Hayek]

Seems pretty obvious to me. Our cities are crazily polluted - very often, you can smell the pollution outside even with the AC on, so it is a no brainier that driving with windows down (or using a two wheeler) is a recipe for disaster. Apart from pollution from other vehicles, our roads are also very dusty - as I have observed while cycling early in the morning. I have always driven only with windows up and the AC on, ever since we fitted an AC in our Maruti 800 back in the early 1990s (we originally had a non AC car). Guess it was not just because of pollution - Bombay weather barring a few days a year requires air conditioning.

Of course at home, I do keep windows open to get fresh air - but we live on a mid teens floor, and at least once when the Dyson guy had come to demonstrate an air purifier, the PM2.5 count in my house was fairly low.

[Reinhard]

Pollution is one. But another very important factor due to which I insist on driving with AC and with all windows closed is flying objects of any kind and size on our roads. Items thrown by ignorant other travelers, stones/pebbles being catapulted from under the running wheels of other vehicles, accidentally thrown out parts from anywhere on the roads - are a direct life risk at speed. Such flying objects can cause life changing injuries or even death given the relative speed of the object and car in motion. The glass can offer at least a small line of defense.

As a rule - I insist on keeping windows rolled up and AC on. I don't compromise on it in fact. No exceptions for anyone who doesn't like AC etc.