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25 Percent of Cars Cause 90 Percent of Air Pollution
HughPickens.com writes: Sara Novak reports that according to a recent study, "badly tuned" cars and trucks make up one quarter of the vehicles on the road, but cause 95 percent of black carbon, also known as soot, 93 percent of carbon monoxide, and 76 percent of volatile organic chemicals like benzene, toluene, ethylbenzene, and xylenes. "The most surprising thing we found was how broad the range of emissions was," says Greg Evans. "As we looked at the exhaust coming out of individual vehicles, we saw so many variations. How you drive, hard acceleration, age of the vehicle, how the car is maintained – these are things we can influence that can all have an effect on pollution." Researchers at the University of Toronto looked at 100,000 cars as they drove past air sampling probes on one of Toronto's major roads. An automated identification and integration method was applied to high time resolution air pollutant measurements of in-use vehicle emissions performed under real-world conditions at a near-road monitoring station in Toronto, Canada during four seasons, through month-long campaigns in 2013–2014. Based on carbon dioxide measurements, over 100 000 vehicle-related plumes were automatically identified and fuel-based emission factors for nitrogen oxides; carbon monoxide; particle number, black carbon; benzene, toluene, ethylbenzene, and xylenes (BTEX); and methanol were determined for each plume. Evans and his team found that policy changes need to better target cars that are causing the majority of the air pollution. "The ultrafine particles are particularly troubling," says Evans. "Because they are over 1,000 times smaller than the width of a human hair, they have a greater ability to penetrate deeper within the lung and travel in the body."
Every year or two we undergo emissions inspections - they use a sensor to measure what is in the exhaust gas, and if things are outside of the required limits, you have to fix it. In addition, they use the OBDII port to see if there are any codes being thrown by the engine, and if there are you have to fix those as well.
Older cars were grandfathered in, and only need to pass whatever the standards were at the time they were manufactured.
Probably because the authors of the study were researchers at the University of Toronto and had access to air sampling equipment set up in the area? Sometimes you have to do the research where you can, rather than where you might want to.
(Also, we only share the same atmosphere on average. For, say, an urban area with lots of vehicle traffic, the amount of soot people are inhaling is going to depend very substantially on the vehicles in local use, with much weaker effects from more distant sources.)
US is worse than many developing nations when it comes to public transportation.
There is no way most people can depend on public transportation in US for regular commute. The frequency, and reach of buses/trains are incredibly poor in most of US. The exceptions are the few big cities - NYC, Chicago, Portland etc., that too if you live in an area close to a station.
Not even Bay Area - a high populated urban area - you can depend on public transportation for daily commute unless you have an option for point to point travel on BART / bus. Try going from Hayward to San Mateo - 25 minutes if you drive, more than an hour if you take a bus. You only have to cross a bridge!!!
The same with many East coast neighborhoods - try Phoenixville PA to Philadelphia on a SEPTA bus.
It sucks to be poor. But in 2015, its better to be poor in a country like India compared to US as poor as a voting block is better represented and their needs better taken care of...and that includes public transportation.
To get a better perspective on what it means to be poor in United States this book is a good beginning - http://en.wikipedia.org/wiki/Nickel_and_Dimed
Tat Tvam Asi
It's easy to meet EPA standards on test bench. Out in the real world it becomes a lot harder. Heavy acceleration is bound to dump all kinds of particulates, NOx, and CO, despite pollution controls like catalytic converters. Things like catalytic converters and other pollution controls run best under constant conditions, with the proper amount of fuel to air, temperature, etc. All of which probably works well while cruising at constant speed down the open road. The moment you start doing stop and go, all bets are off. Hit the gas pedal hard and the fuel mixture goes fairly rich as the engine tries to keep up. I'm not a hypermiler freak, but I do tend to accelerate and brake conservatively (I have a CDL and drive big trucks occasionally as well, which influences my habits) which seems to anger people in city driving, unfortunately. I also try to take curves in a manner that makes things as smooth as possible.
Most people on the road seem to not care one bit about fuel consumption and race from light to light, without actually getting ahead of anyone doing that, nor actually getting anywhere faster. I'm sure emissions could be curtailed quite a bit if everyone just slowed down and cars limited their acceleration to something realistic.
I imagine these horribly-bad 25% of cars emitting the most pollution would do a lot better if people would drive them properly.