>Since all these cars passed the laboratory test, that means there must be something very wrong with the test and the way the standards are enforced. It depend

>Since all these cars passed the laboratory test, that means there must be something very wrong with the test and the way the standards are enforced. It depends how the law is written. Case a) - the cars must never emit more pollutants than specified in these rules - then yes, you are correct. The car manufacturers would be rightly concerned about the wide range of situations they would need to account for. Case b) - the cars must not emit more than the specified amount of pollutants under these specific test conditions (implying hopefully "we understand that the real world performance will differ, and are willing to accept this for the sake of simplicity in testing/lawmaking") - in this case the system is working as intended. I am not sure which case we are dealing with, maybe someone can advise us.