Roadside Emissions Survey in Calif. [Archive] - Bimmerfest - BMW Forums

: Roadside Emissions Survey in Calif.

12-28-2005, 11:17 AM
A friend's mom was pulled off at what appeared to be some kind of check point and was given a smog check. After doing some research, the closest I came to this scenario was this. Anyone been through this? Sounds voluntary, but my friend's mom said that there were tow trucks lying in wait, as if they might tow you away if you didn't pass or found something "fishy".

Roadside Emissions Survey Fact Sheet

The California Department of Consumer Affairs/Bureau of Automotive Repair (DCA/BAR) and California Highway Patrol (CHP) conduct the state’s roadside vehicle emissions survey. The survey's purpose is to provide a "real world" profile of emissions from California’s cars and trucks. The data is used to help measure California's Smog Check program by determining statewide emissions levels and monitoring those levels over time. In addition, the survey is necessary to demonstrate to the U.S. Environmental Protection Agency that California's Smog Check program meets federal emissions reduction requirements for ozone-forming pollution generated by motor vehicles. The study also evaluates various emissions testing procedures. California motorists have been participating in state-operated roadside emissions surveys since 1972.

The study is conducted in phases by four teams, who together visit over 300 locations around the state every year. The sites are chosen by first randomly selecting ZIP codes and then determining sites that are safe for conducting the tests.

At each site, one lane of traffic is coned off for testing equipment. A CHP officer directs randomly-selected vehicles to that lane.

Motorists whose vehicles are selected for testing are greeted by a BAR representative who provides them with information about the survey's purpose and answers any questions they might have. Although participation in the survey is not mandatory; it is critical to the success of the survey. The BAR representative will do everything possible to accommodate motorists who are selected for the survey.

The emissions survey tests vehicles on a treadmill-like device called a dynamometer that is now being used to conduct Smog Check inspections in the state’s smoggiest regions. By simulating driving conditions, dynamometers provide the most accurate emissions readings for hydrocarbons (HC), carbon monoxide (CO), and oxides of nitrogen (NOx).

Vehicles are tested solely for the purpose of gathering data. They do not "pass" or "fail" the roadside emissions tests, so these tests add no additional repair requirements for drivers of high-polluting vehicles. The procedure usually lasts less than 10 minutes.

At the conclusion of each test, the driver receives a Vehicle Inspection Report (VIR) detailing the results. The report may not be substituted for a vehicle's official Smog Check.

In some locations, vehicles may also pass by a Remote Sensing Device (RSD), which uses infrared technology to measure vehicle emissions. The data gathered from the RSDs at these sites is also used only for research purposes.

12-28-2005, 01:15 PM
Just to clarify, I have no idea if the tow trucks where there specifically to tow away vehicles or if they were just there by coincidence.

I got the story from a friend. I'm hoping my friend's mom just misunderstood the presence of the tow trucks, but according to her, no one was being towed.

Still, I wonder why they would be there. Just coincidence? Who knows. This happened in Southern California area.

My guess is that most people don't know that it's just voluntary and just happily submit. Maybe they tow you away if they accidentally find something during the "survey" that has nothing to do with smog emissions (like non-CARB item or no catalytics or whatever).

When I first heard the story, before doing my research, it sounded like a smog check point - sorta like a sobriety check point. After finding that PDF file, it doesn't seem as scary, but I can't figure out why the tow trucks would be there. I can only hope that my friend's mom just misunderstood the presence of the tow trucks.

Then I thought I'd post here to see if anyone else has experienced this in California.

12-29-2005, 01:36 PM
Well, not sure about the roadside stops but I have been on several SoCal car club rides where the CHiP's harassed us by pulling over the most visually-modified cars. They did a very thorough equipment check (including using mirrors on sticks to look under the car) and wrote up any smog violations they could identify.

12-30-2005, 09:09 AM
Wow - that is a bummer.

Sounds like vehicle profiling...

Anyhow, there is a really active and informative discussion here also