Drivers and nondrivers alike have heard of the controversy, or maybe they have seen the notorious television images of Yellowstone rangers bedecked in gas masks at the park entrances taking fees from an endless line of anxious sightseers perched on idling snowmobiles that are spewing smog. Every winter when the snows blanket the northwestern reaches of the state, the rumbling begins anew―literally and figuratively.

The snowmobile fumes begin penetrating the pristine park, and the concerns arise regarding health issues for the employees and the effects on the wildlife. Yet despite the controversy, Wyoming does not require smog or emission checks for any vehicles registered and titled in the state.

It seems the pollution issues in Wyoming center more around snowmobiles and ATVs than any other motorized vehicle. In the past couple years, there have been attempts to regulate the emissions on these types of off-road adventure machines.

But when it comes down to it, Wyoming, despite the occasional plume blights or layered haze concerns, is one of the cleanest and clearest states around. Maybe it is due to the wild Wyoming winds (wind farms galore) or the fact that hardly anybody lives in the massive state, but at the moment there are no emissions requirements enforced by the state.

Just because Wyoming doesn't require smog and emission checks―and still remains a clean state―doesn't mean you should neglect the working order of your vehicle. Check out the Environmental Protection Agency's Web site to find out information about keeping your vehicle running properly and in as environmentally friendly as possible.

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