“If you don’t ask me to take off your catalytic converter, I won’t ask you to pay the $2,500 penalty,” a sign inside Iarrapino's Muffler & Brake Shop in Butler reads.

Catalytic converters reduce pollution caused by emissions by breaking the pollutants they release into less-toxic components. That helps motorists throughout much of Pennsylvania avoid fines for emission violations.

But in counties such as Butler, the only way to enforce laws for these violations requires a visual check, and these laws often are difficult or dangerous for police to enforce.

“We can enforce under the inspection laws,” said officer Jack Ripper, who serves with the Penn Township Police. “It’s just a matter of having the training to do it. ... I have my state inspection license. But I have never crawled underneath a car to look for (the catalytic converter).”

“It’s also a safety issue,” he added, pointing out that the side of the road can be a dangerous place to inspect a vehicle. “You’d have to almost get (the car) off the road and into a parking lot,” Ripper said, and then use a floor jack to raise the car off the ground in order to access its underside. “And we don’t carry that stuff.”

Butler County is among the jurisdictions in the state that do not require an vehicle emissions inspection, according to Pennsylvania Department of Transportation.

Catalytic converters consist of precious, heat-resistant metals — platinum, palladium or rhodium — that trap pollutants within a honeycomb structure. These metals, of course, make catalytic converters common targets for thieves looking to pawn them.

Even shields and other protective equipment designed to safeguard against catalytic converter thefts don’t offer guarantees, Ripper said. Thieves have devices that can cut through shields, and they can take the catalytic converter and leave within minutes.

It’s possible, he said, that manufacturers could develop effective tools to prevent theft, but as of now there is no such technology.

“Probably the only way you can even try to prevent it is (to) park your car indoors” when possible, he said.

Ripper also recommended parking where crowds were more likely to gather and in well-lit places that discourage crime.

Even though there are few guarantees when it comes to preventing catalytic converter theft, there are other measures motorists can take to protect them as the colder months descend.

Colder weather in general is hard on cars, said Marc Iarappino, a mechanic who specializes in emissions issues at Iarrapino's Muffler & Brake Shop, in Butler. He advises drivers to perform all the regular checks they would at any time of year, but to increase the frequency of these checks.

In addition to checks on antifreeze, other fluids and tires, he noted a specific hazard for catalytic converters.

Salt is indispensable in keeping roads from icing over throughout the winter, but salting roads corrodes all metals. The undercarriage of a car often will suffer damage from salt, and that includes the catalytic converter.

“It’s very important to get a coat of oil up underneath your car,” said Marc Iarappino. “Unfortunately, I see a lot of cars with a lot of rust — a lot of newer cars. I see a lot of vehicles in here that have actually failed inspection for rust-related reasons.”

“It’d also be a good idea to get your exhaust inspected,” Marc added.

A converter can cost anywhere from $300 to $1,800, depending on the vehicle, said state vehicle inspector Ralph Lukas. Average replacements run between $180 and $300.

“And then they go up from there,” Lukas said. “If you have to go to a factory, they can be quite expensive.”

Some cars have four catalytic converters, he said, with a pair toward the front and a pair toward the back of the vehicle.

“Somebody could have bought a car, like an older car, and had no catalytic converters on there,” said Lukas. “We’re not the ones that say, ‘Hey, we’re going to give you a fine because you don’t have a converter.’ We recommend you go to an exhaust shop and get a catalytic converter put on.”

He said his team doesn’t give passing inspections and stickers for vehicles that don’t have catalytic converters attached.

“Especially these diesel trucks — that’s a big thing,” Lukas said. “These diesel guys with newer diesels are taking the catalytic converters off of them, and we will not inspect them unless there’s a converter on there that belongs on there.”

Most garages will not accept catalytic converters for sale, he said.

Lukas said drivers should keep an eye on their check engine lights whenever they’re in doubt about the condition of their converters.

Ripper noted that while fines for driving without catalytic converters begin at $25, they also can include court fees that add up to $175. People caught removing catalytic converters from vehicles are subject to $10,000 fines, said Lukas.

So while the price of unleashing unfiltered pollutants into the air might seem small at first, those penalties can reach hefty heights fast if you drive far enough.