How can they possibly do an emissions test on a car as it simply drives down the road?
I got a notice in the mail that my car passed its RAPIDPASS emissions test (required every two years in Northern Virginia to be able to register your car). If I pay the $28 fee, then they will send my record to DMV for registration. I did not do anything to initiate this; apparently they tested my car and photographed my plate as I drove by. Normally I just go to an inspection station and pay the same $28 fee. The inspection stations are private facilities (generally repair shops) licensed by the state to perform the inspection.
With RAPIDPASS, you just drive through some vaguely delineated area and somehow they perform a test that way. How can they possibly do an emissions test on a car without sampling the emissions from the tailpipe? I have no idea how they sample the emissions from a distance and without the driver even knowing about it.
You drive though a “trap” that has an infrared laser on one side, and a detector on the other. The system can measure your emissions by infrared absorption spectroscopy.
It’s better than most smog checks.
These days, most emissions testing is done by confirming that the OBDII system reports all parameters in acceptable range. Which really doesn’t measure emissions - it infers them.
This system actually measures tailpipe emissions when the car is traveling, so somewhat more realistic.
You get a letter from some company you’ve never hear of, saying that they did a ‘test’ on your vehicle that you never consented to, or even noticed when it happened, and that if you will send them money they will then send in to the government to certify that your vehicle has passed this ‘test’, so that months later you can get your vehicle registered.
How about an even better deal?
Send a wire-order money transfer direct to my Swiss bank account for only $20 (nearly 30% discount) and I absolutely pinkie-promise that I will send the info to your state DMV.
This seems like a system just custom-designed to inspire fraudulent scams, with hardly any chance of an average person being able to identify them as scams!
Colorado has had a similar system for a number of years. In our case, the letter comes from your local county with your vehicle registration bill. Just like in Virginia, it seems, the price of roadside emissions and standard emissions are the same, but in the case of roadside you don’t have to do anything extra.
The scanners are generally setup along entrance ramps, and other places where cars tend to accelerate, to get a reading while the engine is under load.
Right, I’m in Colorado and there was one of these that I used to pass, a lot. I was always hoping that I would get a letter saying my car was okay, but nope. I always had to go in and do the test. And my car always passed, quite easily–so I don’t know why it didn’t pass the roadside thingy.
So for that reason I guess I always figured you’d only get a letter if your car flunked. I know that people could report your car if they saw visible emissions under certain circumstances.
I almost hate to admit it, but the State of Washington has done the right thing. As of New Years Day, the State is discontinuing all emissions testing. All the testing stations will be dismantled, and all the employees laid off. Their reasoning is that the cars now are so lacking in dangerous emissions, and there are so few old cars on the road any more, that the tests are no longer needed.
Emissions testing is another prime example of an unnecessary tax on being poor. The working poor are the people who drive these older, out of compliance cars. They are not going to be able to fix whatever is causing the failed tests because they cannot afford to.
So they either drive without fixing them, resulting in further fines that cannot be paid, or dump the vehicle for another piece of shit car.
It is a self correcting problem without a need for government intervention. These cars are not going to be repaired because there is no money. So they will soon be taken off the road anyway. People driving newer cars likely do not even need the tests because their cars comply with emission rules so the testing for them is just another fee or tax.
Tell it to Volkswagen, though – if you are not even going to be tested or your only test wil be a sampling at the factory, people may be motivated to cut corners; and in general when health/safety rules are loosened, I wonder how much potential profit or savings it represents for the industry vs. any “tax on the poor” (who anyway benefit from a cleaner environment) effect. It is true that newer vehicles are lower-emission by design, not requiring regular preventive tuning up to keep them compliant for a long time, but at some point it becomes needed, and if it’s never detected that the vehicle is failing to comply, it will stay on the road a lot longer while noncompliant.
Minnesota did that quite a few years ago.
The emissions testers were reporting that more than 95% of vehicles were passing the test, so it was hardly worth the cost of maintaining a string of test centers, and the cost of DMV workers to deal with the extra paperwork. Even the first year it was required, over 80% of vehicles passed.
It was especially pointless since, by Minnesota law, vehicles older than 12 years were exempt from the testing. And you could get 1-year waiver if repairs would cost over $200. And it only applied in the metro area, so if you drove out into the rural area and licensed your vehicle there, you didn’t have to have it tested.
The state of Washington finally did something right. Starting this Wednesday, no more emission testing in the state. The failure rate is so low now someone figured it was a waste of time and taxpayers money.
After decades of mandatory emissions testing for older cars, the province of Ontario abandoned its stupid emissions-testing program, too. I am an environmental advocate, but stupid is stupid. Most mechanics hated it as a useless tax grab, and my own mechanic hated it to so much he refused to have anything to do with it and it was generally wise not to even bring up the subject with him. Newer cars were exempt anyway, old historic cars were exempt, and the only cars that had to pass the OBD II tests every two years were those that almost invariably passed anyway, increasingly so as the average car on the road became newer with more modern technology. And if they didn’t pass, and the repair was exorbitantly expensive, then the polluting piece of junk would get a “conditional pass” anyway. The whole system – along with some of the insanely strict rules about safety checks when reselling a car – seemed intended to simply put a lot more new cars on the road, which is hardly environmentally friendly when you consider the carbon footprint of manufacturing a whole new car.
To avoid criticism of a tax grab, a few years ago the Ontario government made the inspections free – that is, the government paid for them. Which didn’t make the mechanics happy, either, presumably because they were getting lower rates. One guy had a big sign up: “Nothing is free – it’s all paid for with YOUR tax dollars!” Now, thankfully, we’ve seen the end of it, because we don’t need it any more. The only exceptions are heavy big trucks.
The typical location is a highway on-ramp where you are accelerating, i.e. you’re making a significant amount of power (and therefore a useful amount of exhaust). The measurement is optical: the system is sending a light beam across the roadway, roughly through the region where your car will be spewing exhaust, and a receiver on the far side of the road measures the attenuation of specific wavelengths of the beam by the components of your exhaust. The higher the concentration of criteria pollutants in your exhaust, the more certain wavelengths of the beam are attenuated.
Formal compliance testing of a vehicle or engine in an EPA or manufacturer test cell is done under exacting conditions to assure repeatability. The vehicle is “soaked” at a specified temperature for a specified time before the test, the test cell is kept at a specific temperature, the vehicle/engine is driven through specific sequences of speed/distance, the the exhaust is handled in a very specific manner (e.g. it’s passed through a “dilution tunnel” to simulate atmospheric mixing/chemistry before measurement), and so on. (if you want to know ALL the requirements for how to conduct a vehicle test, well, here ya go.) By comparison, as you might expect, a drive-by emissions test isn’t terribly precise because it doesn’t control for many of these factors. OTOH, it doesn’t need to be that precise, because when cars go bad WRT emissions, they tend to go really bad. The drive-by test isn’t looking for cars that are 5-10% over the limit, it’s looking for cars that are 5-10 times over the limit, and that kind of discrepancy is relatively easy to spot with a drive-by test.
The primary value of the drive-by test is that it reduces the inconvenience to most drivers by eliminating the need to go somewhere just for a smog check - unless the drive-by test specifically shows that your vehicle probably has an issue. If it does, then you are required to go to a mechanic shop for a more accurate emissions check. The drive-by test can also show model-by-model trends that can indicate a broader model-related problem that might justify an investigation/recall. For example, after the Volkwagen emissions scandal several years ago, a check of Colorado’s aggregated drive-by-emissions data clearly showed that certain VW models emitted a lot more on the road than they did in a test cell.
The limited extent of the testing (esp. the limitation to the Twin Cities metro area) was likely related to a failure of the region to meet one or more National Ambient Air Quality Standards (NAAQS). When this happens, the state is required to submit a State Implementation Plan (SIP) describing actions the state will take in order to bring local air quality into compliance. Vehicle emissions testing, restricted to just the metro area, was likely one aspect of their SIP. If they’ve eliminated this test program, it likely means that they’ve achieved NAAQS compliance and had reason to believe the program was no longer necessary.
“Environmentally friendly” depends on what aspect of the environment is being considered.
There are two different aspects of a car’s emissions that are kind of in tension with each other. One is the carbon footprint, which seems to be all the rage these days. The carbon footprint does matter - for your great-grandchildren and their descendants. But the other aspect is the immediately noxious emissions, most notably raw hydrocarbons, NOx, and particulate matter (PM), and these will adversely affect your health today. Engines/vehicles could be made more efficient (lower carbon footprint) in a heartbeat if we eliminated the restrictions on HC/NOx/PM emissions, but present-day air quality would quickly turn to shit. In fact, even with current emissions standards, air quality in many cities in the US (e.g. Los Angeles) is already a problem. Cars are vastly cleaner than they were 50 years ago, but there are also far more of them now, and we drive them much more than we used to.
NJ has eliminated safety testing, eliminated emissions testing on old vehicles, and only does the OBDII testing on newer vehicles (every 2 years), with brand new vehicles getting a 5 year exemption.
The inspection station I went to recently looked like a ghost town. 10 years ago, it was like the hottest bar in town, with a line out the door and around the block.
A mass spectrometer has a vacuum in the testing chamber, so that only the substance being tested is, well, tested. Lord knows what other gases are present with this method, which is probably why some flunk the “outside” test and pass the “inside” test.
For the roadside emissions check, the gases present are a blend of car exhaust and atmosphere. This is the same mix that’s analyzed in test cells during compliance/certification testing. In the test cell, part of the test procedure is assessing ambient/background levels for all criteria pollutants before starting the vehicle; the vehicle’s output is then the difference between the test measurement and the background. The roadside test equipment would necessarily need to do the same thing, i.e. assessing background levels in the time shortly before a vehicle passes by.
Probably the largest source of imprecision in roadside testing comes from mixing of exhaust with ambient air as the vehicle passes the test apparatus. In a test cell, the flow rate in the dilution tunnel is measured, so the dilution ratio is known. With roadside testing, they must assume some dilution ratio, and no doubt it ends up being way off every now and then. Probably not surprising that a few healthy cars fail the roadside check and then pass the garage check. There are probably also some dirty cars that pass the roadside check and receive no further scrutiny. Overall the benefits of roadside checking (in terms of convenience and cost savings) would appear to outweigh the detriment (letting a few dirty cars get by in any given registration year).
I think our last California emission test was around 1989, just before we moved from an urban-corridor area to coastal mountains, and later the Sierras, outside mandatory smog-check zones. Our vintage smokers never needed further work. Now we run a Sprinter diesel on a 2015 platform. It’s supposedly clean but we’ve never had to find out. If we innocently run it past any other states’ drive-by smog checks, should we expect a mailed notice?
Thanks, Machine Elf. What sort of sensors detect the presence of a car and the location of the tail pipe? If it is able to “see” the license plate, it has a general idea of the car’s orientation.