Cities are converting their fleet of buses over to greener cleaner burning natural gas buses and more trucks are being required to wear particle diapers. So urban air is slowing improving. In the meantime, a few tips to duck that diesel plume.
If you have green fever, you already know all of the eco-friendly things you can do. The trick is to set an example and include people in your efforts without seeming like you're trying to forcefully convert them.