Air conditioner manufacturers asked the Environmental Protection Agency August 15 to close a regulatory loophole that allows for the continued sale of units that use an ozone-depleting substance. The agency issued a final rule in December 2009 banning the sale and distribution of new AC and refrigeration products and components that are pre-charged with HCFC-22 and HCFC-142b, and the companies want the agency to ban the sale and distribution of new subsystems as well.