“I get off the plane at six o’clock after doing a users’ conference in Duesseldorf, and my phone blows up,” recalls the president of Sensors Inc. “All of a sudden here comes an email and a text and a text and an email and an email and a text, and before the weekend was over there were 700 stories on the Internet!”

The stories were about the Volkswagen emission scandal: diesel engines designed to show low pollution in the lab turned out to belch as much as an eighteen-wheeler on the road. And Morrill saw something familiar in the photos that illustrated them: portable emissions measurement systems (PEMS) designed and built by Sensors, a company born in Ann Arbor and now based in Saline.

The company was founded in 1969 to commercialize infrared technology developed at the U-M’s Willow Run Laboratories (later the Environmental Research Institute of Michigan). Its big break came the following year, when Congress mandated tighter air pollution rules for cars and created the Environmental Protection Agency to implement them. “That led to the start of the inspection and maintenance programs where people bring their vehicles in to get [emissions] tested,” explains Sensors VP Rob Wilson. “We made the measurement devices that determined whether you pass or fail.”

Sensors dominated that market. “Eighty percent of the analyzers in this country were probably ours,” says Wilson. From its headquarters and factory on State Rd., “we’ve sold close to 350,000 here and in Europe and Asia. This was our bread and butter.”

But in the 1980s, carmakers started installing electronic engine control systems–and it became clear that the EPA would let shops check emissions simply by plugging into cars’ on-board diagnostic (OBD) ports. “So no more tailpipe testing,” says Wilson, who hired on in 1986. “Our business was going away.”

A 1998 emission scandal changed Sensors’ luck. “The EPA discovered [truck engine] manufacturers had algorithms to pass certification requirements for their engines,” says Wilson. Just like the recent Volkswagen cars, the trucks looked good in the lab–but emitted as much as ten times as much pollution on the road.

The manufacturers agreed to $1.2 billion in fines and penalties–some of which the feds reinvested in developing portable emission measurement systems small enough to be carried on a truck. “We worked very closely with the EPA,” says Wilson. “They didn’t know if it could be done.”

Sensors figured out how to do it–and eventually, how to miniaturize its PEMS units to the point that they could be carried by even smaller vehicles. “It’s basically a lab in a box,” says Wilson, “what we call our Semtech DS. It had laboratory-grade analytical capability, but you can put in on any vehicle of any kind, any engine, anywhere.” Mounted on a trailer, it can even test the exhaust of motorcycles and snowmobiles.

Semtech made Sensors the industry leaders once again. “Everybody uses the equipment,” says Wilson, “all the research institutions, the academics, the agencies. We probably have close to a hundred customers throughout the world.” And that was before the Volkswagen scandal drove home the need for on-the-road emissions testing.

The impact has been “unbelievable,” Wilson says. The company does not release financial data, but since the news broke in September, he says, PEMS sales have doubled. “There’s going to be a huge move to on-road testing,” says CEO Don Soenen. “It’s going to become the standard.”

Soenen bought the company from its founders in the late 1970s, sold it to a larger company in the 1980s, then bought it back in 1991, and sold it to its employees in 1998. He handed the president’s post to Morrill last summer, but remains the company’s elder statesman and guiding spirit.

“The Volkswagen issue has gone viral worldwide,” Soenen says. “Korea is just as concerned about this as they are here and in Europe.” Even China is finally getting serious about cleaning up its horrendous urban air pollution. And carmakers and regulators in those countries will all need portable emissions measurement systems.

With Sensors’ success guaranteed for the foreseeable future, the sixty-nine-year-old Soenen has moved on to other challenges, including turning a former Plymouth middle school into an arts and recreation center. But “I still hang out here,” he says with a smile.

“If I’m here, I’m going to say something,” Soenen adds. Despite the vast changes in the auto industry and emissions regulation since Sensors was founded in 1969, “the laws of physics haven’t changed very much.”