By now, many owners of diesel-powered Volkswagens are looking at their VWs and wondering if the vehicles are really as fuel-efficient and eco-friendly as they’ve been touted to be.
On September 18th, the EPA sent a violation notice to Volkswagen alleging that the German car company built and sold diesel-powered cars that used special software to sense when a vehicle’s emissions were being tested and turned on emissions control systems in response. The software then turned off the emissions controls when the vehicles were in normal use, the EPA alleges. On Sept. 22, Volkswagen admitted that the software is present in 11 million vehicles worldwide that contain the affected engine type.
The company’s stock price has nose-dived since the revelations, Volkswagen has stopped selling cars with the affected engines in the U.S., the CEO resigned, and there’s been talk and speculation of fines and even criminal charges. It’s anyone’s guess how long it will take for the air to clear, but the Volkswagen emission is something of a teachable moment for those of us in the polymer testing industry. The discrepancy between the results Volkswagen said emission tests would reveal and what an outside third-party testing organization actually found illustrates the need for and value of what we call out-of-specification (OOS) investigations.
The existence of the software in question came to light when an outside group, the International Council on Clean Transportation, decided they wanted to figure out why laboratory tests and real-world performance for several VW diesel models varied widely. The discrepancy was concerning because it’s widely known that vehicle emissions controls can affect the power, performance and efficiency of combustion engines. The marriage of EPA-compliant emissions and superior fuel efficiency were selling points for the vehicles.
The ICCT’s research found that on the road, some of these vehicles were putting out far more nitrogen oxide than permitted by EPA regulations. Nitrogen oxide, by the way, is a major component of smog.
How do Volkswagen’s woes allow us to segue into science?
Here’s the thing: It’s not at all uncommon for researchers and scientists to run tests expecting a certain result only to end up with actual results that widely diverge from their expectations. There are a variety of reasons as to why that can happen.
On one extreme is intentional deception, which is what the EPA is alleging happened in the VW case. It could also be possible that a manufacturer didn’t properly understand the material they were using and its performance capabilities. Or, an error with the testing procedures or sampling issues could be to blame for unexpected results.
Although the Polymer Solutions team doesn’t do emissions testing, we do know the value of OOS investigations. These investigations occur when we conduct analysis and the results are outside of what is expected by either our team or our client. As part of the OOS investigation we ask a series of questions to discover what happened to lead to the unexpected results. Is the material not what we thought it was? Was there a problem with the sample? Did the client have realistic information about performance characteristics of their material? Was there human error involved in conducting the analysis? This investigation is launched within our Quality System in conjunction with members of our Quality Assurance team to make sure all avenues are explored in a well documented way.
When test results unveil a discrepancy between what’s expected (or claimed) and what’s actually true, it’s in everyone’s best interest to discover what’s causing the variation in a methodical and documented manner. Unexplained and unresolved discrepancies can undermine the performance of a product, erode consumer trust, and – in VW’s case – put a company at odds with regulators.