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Air conditioning

This sounds like a really stupid question - but air conditioning in cars - it is presumably just drawing in the air from outside and cooling it down, so allergens will end up in the car?

I'm driving in a new country, and am struggling, especially when sitting in the front near the air con. Am I going mad, or is that plausable? I'm crossing big distances, going quite quickly through very changing landscapes.

I'm not sure what to do... it's somewhat unavoidable, but I'm living on Ventolin much more than normal.

8 Replies

Most air-con units in cars have a pollen filter. However if you are stuck in traffic it might be woth changing the settings to recycle (car with a arrow going in a circle inside) so that you are not sucking in the fumes from outside. I automatically change the settings as soon as I am stuck in a jam!



I always get set off by the fan in the car...but my boyfriend says his pollen filter looks like it had a whole tree shoved though it - so that would probably explain it!


Also running Air Con in a car for more than half an hour can produce ozone in the car - Ozone is a know trigger for asthma.

I can't run my air con for very long as it affects my asthma. I turn it on & off quite a lot!


BTW Motability refused to sanction a new pollen filter to be fitted to my car at its annual service! Ford sugests that they are changed yearly.


I agree with Kate regarding air conditioning units generating ozone. I'm not allergic but the ozone definitely sets me off if I have the air con on for any length of time. I've decided I'd rather be hot than breathless !


That's interesting. I never really use air con in cars - I dont travel in them much, but I'm currently driving coast to coast across America, and it's hot at the mo in Texas.

I dont think there's much I can do... I'm travelling with others who would get v hot!

I've upped my Seretide to 6 puffs daily (Seretide 250), intead of 4. I dont really know what else to do. We'll be using air con until late November (at which point it will go incredibly cold where we travel!)... I guess just keep on the Ventolin. If I was in the UK, I wouldnt be worried in the slightest, but because I'm in a different country which seems to be making me worse, and I'm here for a while, I'm a bit concerned.


Ozone from air conditioning systems - myth versus reality

Hi guys,

Must stick ma wig in here - LOL

Air conditioning systems (as far as I am aware) do NOT produce ozone.

Ozone is a recognised respiratory sensitiser (substance capable of promoting an allergic response even in persons who do not have a history of asthma or allergy) and is registered under the control of substances hazardous to health (COSHH) regulations.

Logic would suggest that car manufacturers would not be permitted to install aircon systems in cars if they presented a serious risk to human health. Introducing ozone into a confined space (like a car) would present a major risk to health.

Perhaps there is some confusion about the type of refrigerant used in some of the older aircon systems that are were charged with CFC (an ozone depleting chemical)?

Aircon systems work on a basic principle that fresh air is blown over cooling coils (a bit like a car radiator) which are charged with refrigerant gas that indirectly chills the air as it passes over the cooling coils.

If you are having problems with your aircon, perhaps you need to consider getting a wig - they are brill for wafting the air about whilst in the car. When I am in my car and feeling a bit hot, I check round (not forgetting the rear view mirror of course) to make sure no-one is watching, then slip off my wig and use this for creating air movement by wafting the airspace in front me. Just be careful the traffic cops don't see you doing this as you could get pulled over for causing a distraction to other road users - LOL

Take hair,



Thanks Derek and your wigs of wisdom for that.


Thanks, Derek, I was a bit confused about that, as I had heard the ozone story too from a respiratory doctor, but I knew it was a COSHH regulated substance, so was a bit puzzled.

Personally, I don't have a car with air con (I wish!) so maybe the system they use in cars would affect me a bit differently, but I do have a big air con unit in my bedroom. My grandparents very kindly bought it for me last year after the heat wave last summer had me in hospital more than out. It was pretty expensive - around £500, I think - but it's a proper big unit with two large vents that vent the hot air and excess moisture outside. Before we had it we used to suffer from excess condensation in our room due to the double glazing and absence of airbricks (which would have cost quite a lot to put right) and once or twice we had to remove mould from the walls due to the damp - not what you want in your bedroom whether you're asthmatic or not (when I say 'we' had to remove mould, I do of course mean that Alex had to remove mould!). The unit also ionises and has a pollen filter. It's powerful enough so that if we shut all the other doors apart from the bedroom door upstairs, it will cool the dining room and living room downstairs too.

Of course, this summer it hasn't really come into play very much with the weather we've had! - although we do still run it for an hour or so each day to keep the moisture levels down. It's got a timer on it so you can set it to come on for an hour a day. When it was so hot last year, it did make a palpable difference - I would come in really struggling from the heat, and almost immediately feel better going in to my airconed room.

It is a lot of money to spend, though, without knowing whether it will help, or even perhaps make things worse - if you have a friend who has home air con, it might be an idea to invite yourself round and see how it affects you! I have a friend with brittle asthma who has an air con unit in one room of her house and basically lived in it last summer - and it worked to keep her out of hospital! As I said, I think car air con units may well be somewhat different - I don't know if it's the size of the filter or the fact that there is a lot more exposure to carbon particulates when you are driving on a busy road - my house doesn't get stuck in that many traffic jams!

I guess everyone reacts differently to these things - and one persons relief is another persons trigger - so it pays to do your research.

C, I don't think I have any specific useful advice - except to maybe try sitting in the back all the time, if you're worse in the front, but I'm sure you've already thought of that. Do seek medical attention, though, if things are getting out of hand. Other than that, hope you're having a good trip!

Take care all



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