Editor’s note: This is the second in a two-part series about diesel emissions and air quality. Part one explored moves by counties to implement diesel testing for cleaner air.

As county health departments work to curb emissions, one of the big fish they hope to catch is smoking vehicles. And at the state level, a new bill could help give them the teeth they need.

Smoking vehicles are often the result of intentional tampering with a vehicle’s clean burning programming. Excess fuel gets pumped to the engine, and the result is black, sooty exhaust.

While these modifications were used to increase towing power in the past, these days they’re more often associated with the anti-society and anti-environment “Rolling Coal” movement. Drivers use their tampered vehicles to blast exhaust on pedestrians and Prius drivers.

“What you need to do is go on YouTube and search ‘rolling coal,’” said Dennis Keith, manager of the Air Quality Bureau at the Davis County Health Department. “It’s becoming quite a phenomenon.”

Snuffing out the smoke

Despite efforts to crack down on car pollution, smoking vehicles remain a problem, even in counties actively working to improve air quality.

“We receive several complaints from the public throughout the year about diesel trucks that smoke,” said Brian Cowan, deputy director of environmental health at the Weber-Morgan Health Department.

While the health department doesn’t have complete records for the number of complaints beyond the past two years, the number of reported smoking vehicle in Weber County jumped from 53 in 2013 to 100 in 2014. Those numbers don’t include vehicles registered in different counties or misreported license plate numbers. 

Part of the problem is, unlike gasoline cars, emissions testing for diesel vehicles isn’t required by the U.S. Environmental Protection Agency. Only two counties have elected to form their own diesel testing requirements, making it easy for many of the state’s smoking trucks to fly under the radar.

“That’s one of our concerns,” Cowan said. “If we’re not testing those vehicles, we don’t have an effective way to address them. If we implemented an inspection program, that would help.”

A preliminary study in Davis County found that the black smoke from modified diesel vehicles has more than 100 times the concentration of small particulates that cause inversion air gunk and breathing problems.

“The darker the smoke coming out, or what we refer to as opacity, the more the pollutants you’ll find,” said Chuck Gee of Worldwide Environmental Products, an emissions testing contractor with Davis County who helped with the study. “A vehicle that’s running poorly needs to be fixed no matter what. If it’s been tampered with … it needs to be brought back to (its) certified configuration.”

That’s why health departments in Weber and Utah counties are now exploring the idea of implementing new diesel testing requirements to address the problem. But even the counties requiring diesel emission inspections face problems of their own.

“We have people who don’t like our test, who will pass our tests then tamper or hit a button and blow smoke as they’re leaving (our Davis County emissions testing center) parking lot,” Keith said.

From there, it could be two years before the county has an opportunity to test — and possibly fail — the vehicle owner again.

A cloudy issue

All five of Utah’s counties with emissions testing requirement have hotlines to report smoking vehicles. Growing public awareness of the smoking vehicle problem along with easier tools for reporting them partly account for the jump in complaints at the Weber-Morgan Health Department. But when it comes down to it, there’s not much health departments or law enforcement can do to get these vehicles off the road or require them to be fixed.

“People can report smoking vehicles to our Davis County website. We also have GoPro cameras on some of our (county) cars, so when our scientists are out doing work and they see a car or truck smoking, we can film them,” Keith said. “We only had the cameras for a week, and we caught a car, a gasoline car, blowing smoke.”

From there, health department employees will collect license plate numbers and send a notice to the vehicle’s owner, summoning them to the emissions testing center to get their cars or trucks tested fixed.  

But if a vehicle owners ignores the notice, the county health departments have no legal recourse. They can’t revoke registration and they can’t issue fines.

According to Cowan, officials at the Weber County Health Department have tried that in the past, but found they didn’t have any legal clout backing them.

“It’s something we did for a short amount of time until it became evident that the DMV didn’t have authority they thought had been legislated,” he said. “So currently, if someone calls in one of those trucks, ... we send that vehicle owner out a notice and ask to make repairs. But there’s really no follow up. We don’t know if it gets taken care of.”

In Weber County, since diesel vehicles currently aren’t tested for emissions, there’s no chance of catching a Rolling Coal driver, even when they’re up to renew their registration.

In Davis County, where diesel emission tests are required, Keith said the health department received 190 smoking vehicle complaints last year. Half of those vehicles were registered in another county. Another 58 came in to be tested, but that means more than a third ignored the county’s notices. All they can do is hope to catch those vehicles at their next emissions test.

“We just have a lot of challenges when it comes to trying to cut down on smoking vehicles in our county,” Keith said.

Getting lawmakers on board

That could all change if a new bill gets passed by the state Legislature. House Bill 110, introduced by Rep. Patrice Arent, D-Millcreek, this month, would grant the authority for county health departments to rescind registration after smoking vehicles are caught or reported.

“I get calls every day of the week from constituents who see these smoking vehicles on the road, and I’ve also been contacted by health departments in the five counties that do emissions inspections,” Arent said. 

Arent is the founder and co-chair of the bipartisan Clean Air Caucus, which has made clean air legislation a priority. 

“The DMV has the authority to revoke registration for a lot of reasons ... what my bill would do is say, ’this is one more reason,’” Arent said. “Now, the counties will work with people to make those repairs ... no one wants to revoke someone’s registration, we want to give them an opportunity to fix their vehicle.”

In last year’s session, the Legislature passed more clean air legislation and appropriations than the past decade combined. Arent said that, so far, HB 110 has received a positive response from counties and her fellow lawmakers.

“You never know whether you’re going to have pushback until take to the House floor, but I think there’s a lot of support out there,” she said.

Based on the number of calls he receives, Keith expects widespread backing for the bill as well. 

“I know the smoking vehicle program gets a lot of support. You’ve got that small minority group that thinks it’s their constitutional right to blow smoke,” Keith said. “But the general, overall public is happy that we’re here doing what we’re doing.”

Contact reporter Leia Larsen at 801-625-4289 or llarsen@standard.net. Find her on Facebook.com/leiaoutside or on Twitter @leialarsen.

Report smoking vehicles

Davis County Health Department

(801) 546-8860


Weber-Morgan Health Department



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