Emission Testing: Real World vs. Controlled Lab
Maybe you've heard about the big scandal involving the car manufacturer, Volkswagen.
In September, U.S. authorities revealed test results that showed Volkswagen had programmed cars to emit lower levels of harmful pollution - only when the cars were undergoing emissions tests not when they were on the road.
Emission just means something that is discharged. And in this case, it's the emission of air pollutants from car engines.
Volkswagen admitted that they cheated on emissions tests involving about 11 million diesel vehicles. Now there is more scrutiny than ever about emissions testing. Governments worldwide rely on car makers to police themselves when it comes to emissions.
Sherisse Pham visits one independent test house who says its test results are far more accurate than those found in a lab.
Animated Diagram: Animated Engines: Diesel Engine
Website: Ohio Environmental Protection Agency, Vehicle Testing Procedures
Website Article: Union of Concerned Scientists, Cars, Trucks, and Air Pollution