More pollution inhaled in a car than on a bike.
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Drago
Legendary Member
- Location
- Suburban Poshshire
Unfortunately, visual conspicuity does nothing to address the problems of other road users either not looking or driving inappropriately. They are only of benefit around drivers who are already paying attention and driving with a suitable level of care, and these drivers present little risk in the first place. This is why no firm evidence of reduced accident rates among vis vis wearers can be found - the results are equivocal, and that's being generous.
See, science again! Science looks at evidence, and where there is none it reports back as such.
See, science again! Science looks at evidence, and where there is none it reports back as such.
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kingrollo
Guru
Pop onto the recumbent section. They will tell you that they aren't less visible the regular bike riders.
I haven't got the clout of information to dispute the extensive research that people \ organisations have put into research of these things. So I wouldn't claim they are all wrong.
But I act on my judgements. I nearly always ride with a flashing light, wear a pollution mask for commuting and don't do the black ninja thingy.
Randy Butternubs
Über Member
I don't know why some see it as 'common sense' that cyclists breathe in more pollution than drivers.
There are clearly points in cycling's favour:
1) You are generally further from the source of pollution (how many filter through traffic on the drops?)
2) You spent less time sitting in heavy traffic.
And points against:
3) You are breathing more.
4) Many cars have filters which remove some* of the pollution.
So whether cyclists inhale more pollutants than drivers doesn't seem obvious to me one way or the other. Surely scientific studies are the only way to know?
*I feel like some people are ignoring the fact that car filters, even if effective, only remove particulates. I'm pretty sure they do nothing for CO or NOx emissions. Also the finer particulates are both more deadly and harder to filter out so filters which remove most of the particles are not necessarily all that useful.
There are clearly points in cycling's favour:
1) You are generally further from the source of pollution (how many filter through traffic on the drops?)
2) You spent less time sitting in heavy traffic.
And points against:
3) You are breathing more.
4) Many cars have filters which remove some* of the pollution.
So whether cyclists inhale more pollutants than drivers doesn't seem obvious to me one way or the other. Surely scientific studies are the only way to know?
*I feel like some people are ignoring the fact that car filters, even if effective, only remove particulates. I'm pretty sure they do nothing for CO or NOx emissions. Also the finer particulates are both more deadly and harder to filter out so filters which remove most of the particles are not necessarily all that useful.
mjr
Comfy armchair to one person & a plank to the next
- Location
- mostly Norfolk, sometimes Somerset
[QUOTE 5000430, member: 9609"]Vehicles intake outside air just below the windscreen - on many SUVs this height could well be as high if not higher than a roadie on the drops.[/QUOTE]
So where is the air just below a car windscreen coming from?
Thanks to the bodywork shape, the stuff flowing over the air intakes is coming from a little way above road height (basically from a little above the bottom of your front spoiler/skirt), pretty much right where the car in front's exhaust is venting. Not long ago, a fair chunk of that dirtiest air would be used to cool the engine, but current cars don't take in anywhere near as much air for cooling as they used to.
Now, where does the air that a roadie on the drops is breathing come from? (source)
Much higher up. The exhaust-height air near the ground is left near the ground and at worst flutters around their legs. I suspect more upright town/trade bike users will have their air intakes even further from the crap, but it's not easy to find aero plots of them for some reason
I think it's pretty easy to see how car occupants suck tail pipes more than cyclists. Even if car occupants switch to e-bikes and they're not getting much exercise, the reduced pollution intake will probably do public health more good than if they switched to electric cars - that's one reason why it's so awful that government is subsidising e-cars but not e-bikes.
So where is the air just below a car windscreen coming from?
Thanks to the bodywork shape, the stuff flowing over the air intakes is coming from a little way above road height (basically from a little above the bottom of your front spoiler/skirt), pretty much right where the car in front's exhaust is venting. Not long ago, a fair chunk of that dirtiest air would be used to cool the engine, but current cars don't take in anywhere near as much air for cooling as they used to.
Now, where does the air that a roadie on the drops is breathing come from? (source)
Much higher up. The exhaust-height air near the ground is left near the ground and at worst flutters around their legs. I suspect more upright town/trade bike users will have their air intakes even further from the crap, but it's not easy to find aero plots of them for some reason
I think it's pretty easy to see how car occupants suck tail pipes more than cyclists. Even if car occupants switch to e-bikes and they're not getting much exercise, the reduced pollution intake will probably do public health more good than if they switched to electric cars - that's one reason why it's so awful that government is subsidising e-cars but not e-bikes.
mjr
Comfy armchair to one person & a plank to the next
- Location
- mostly Norfolk, sometimes Somerset
[QUOTE 5000818, member: 9609"]those air flow diagrams look good for the open road where I doub't vehicle pollution is significant. And in stop start city traffic where pollution is a major issue the air flow characteristics will be nothing like that.[/QUOTE]
Yes, it's a bit different when stopped, but even then, the car's "mouth" is still closer to the shoot than most riders' - try sitting on your bike leant right over and getting your head down to car cabin air intake level.
But when you're moving, the exhaust is swept up onto the bonnet from fairly low speeds in a way that doesn't happen for cyclists at all. I suspect you might get almost as much exhaust on your face if you rode along slipstreaming an estate car but that would be a bad idea for many other reasons!
Yes, it's a bit different when stopped, but even then, the car's "mouth" is still closer to the shoot than most riders' - try sitting on your bike leant right over and getting your head down to car cabin air intake level.
But when you're moving, the exhaust is swept up onto the bonnet from fairly low speeds in a way that doesn't happen for cyclists at all. I suspect you might get almost as much exhaust on your face if you rode along slipstreaming an estate car but that would be a bad idea for many other reasons!
classic33
Leg End Member
And the science behind a flat earth?
classic33
Leg End Member
[QUOTE 5000464, member: 9609"]I'm glad someone else is willing to stick their neck above the parapet and question some of this in depth research that too often just defies all logic and common sense and puts cycling onto some pedestal.
Recumbent riders are as visible as tradition cyclists.
Ninja's are just as visible as those in hi-viz
Helmets don't help in a fall
You're less exposed to pollution being on a bike on congested city roads.
Breathing fast and deeply lowers your exposure to pollutants.
I too struggle to get my head round some of this stuff.[/QUOTE]
So should a recumbent be more concerned about the exhaust fumes than a diamond frame rider?
Recumbent riders are as visible as tradition cyclists.
Ninja's are just as visible as those in hi-viz
Helmets don't help in a fall
You're less exposed to pollution being on a bike on congested city roads.
Breathing fast and deeply lowers your exposure to pollutants.
I too struggle to get my head round some of this stuff.[/QUOTE]
So should a recumbent be more concerned about the exhaust fumes than a diamond frame rider?
All of it. Otherwise you'd suffocate and die.
mjr
Comfy armchair to one person & a plank to the next
- Location
- mostly Norfolk, sometimes Somerset
Don't the windows open on your car, then?
Slick
Guru
Like most people, I have an opinion and it's far from scientific but does come through experience and I hate getting stuck behind a line of cars especially if I see the TD warning on the back. I reckon you can taste it, I also reckon in certain weather conditions there's a stretch of my commute where there feels like your cycling in an invisible blanket of the stuff. I come over a bridge enjoying my ride with no sign of any traffic movements, and as I descend, I can feel myself getting immersed in it. I don't drive to work the same route so I'm not entirely sure if you get the same smell in a car.
Tin Pot
Guru
[QUOTE 4991603, member: 45"]But read the research.[/QUOTE]
Pah. I have all the facts I need:
[QUOTE 5000464, member: 9609"]
I too struggle to get my head round some of this stuff.[/QUOTE]
You lose, User!
Pah. I have all the facts I need:
[QUOTE 5000464, member: 9609"]
I too struggle to get my head round some of this stuff.[/QUOTE]
You lose, User!
