Arizona lets dirty trucks earn pollution credits for cleaner ones

The US environmental regulators are proposing a new rule for Maricopa County, Arizona. It lets fleet owners earn pollution credits by replacing old, dirty vehicles with cleaner ones.

For years, companies that wanted to build new factories in polluted areas had to find other polluters to pay to clean up. This new rule creates a new class of pollution credits. Now, a trucking company can get paid to upgrade its fleet, and a new factory can buy those credits to offset its own emissions. This means a new source of money for fleet upgrades and a new way for factories to get permits.