• 08-15-2014
    mtbxplorer
    Bikecommuters Breathing Only 1/5 the Pollutants of Cagers
  • 08-15-2014
    newfangled
    Meh. Measuring the pollutants that a sensor is exposed to is a pretty crappy methodology, if they don't also take into account the breathing rate of a cyclist versus a driver. I don't know that it would be a 5x difference, but without it the results are pretty meaningless.
  • 08-15-2014
    BrianMc
    Sounds like a decent cheap pilot study to raise funding. Now they need artificial sinuses and lungs at the same breathing rates as drivers, cyclists, and pedestrians.

    Aren't those infamous cabin air filters supposed to cut a lot of the particulate pollution, at least? Of course you might not get the window down fast enough in the case of flatulence. The dissipation from cycling has to aid anyone in your wake. :)
  • 08-15-2014
    Harold
    I have used the sorts of testing devices that this study likely used. It's a pump and filter you wear for a certain amount of time. It samples the ambient air. Sure, breathing rates play a major role any time you're talking about inhalants, but that doesn't change the fact that concentrations of pollutants was higher in car cabins than with other modes of transport. Other studies already show that the cabins of cars tend to concentrate pollutants so that's not surprising.

    This was a really shitty article, when it comes down to it. "Fumes" is actually a technical term, and does not mean soot from an internal combustion engine. It is not interchangeable with "vapor", either.

    OSHA defines fumes as:

    Quote:

    Fume. Airborne particulate formed by the evaporation of solid materials, e.g. metal fume emitted during welding. Usually less than one micron in diameter.
    Exhaust is not an evaporated solid. The author of that article just used the wikipedia/Webster's definition, which simply provides popular usage, not technical terminology.

    It's pretty remarkable exactly how nasty a car's cabin can be with regards to airborne pollutants. I did a paper in a master's level class about environmental risk assessment where I discussed my personal risk of inhaling benzene from secondhand smoke. If you are in a car with a smoker (or in a car where someone has smoked in the past), your exposure is WAY higher than it would be in a house or other confined space. But importantly, that exposure also varies hugely based on the car model, and whether the windows are up or down.

    The study mentioned in the above article will be very similar. Car model will make a huge difference, as well as whether the windows are up or down. Down will increase air circulation and reduce pollutant accumulation in the car.
  • 08-16-2014
    BrianMc
    Quote:

    Originally Posted by NateHawk View Post
    It's pretty remarkable exactly how nasty a car's cabin can be with regards to airborne pollutants. ... Car model will make a huge difference, as well as whether the windows are up or down. Down will increase air circulation and reduce pollutant accumulation in the car.

    Unless passing an obvious noxious emission source, of course. Like a chipped Ram truck spewing smoke. With off-gassing of new upholstery, sounds and vibration deadening materials, and plastics, I wonder if that new car smell is something we avoid along with a chunk of depreciation, if we buy a 2-4 year old car? Some have commented that BMW's are an unusual (unpleasant?) smell especially when new.

    I can see me with an air sampler hunting for a replacement car in a few years!