"The PM and NOx levels are more in line with reality now, says McClelland about the new rule for off-road equipment, "and it slides compliance a couple of years forward. The way it treats PM is not nearly as stringent either. ARA also specifically proposed and supported averaging provisions so rental operations wouldn't be forced to change the way they do business because the rental business model in the U.S. is based on renting the newest, cleanest equipment in the market."
Smaller companies and smaller operators with a couple of older pieces of equipment will likely be challenged most by the rule, although a few of the changes, specifically an increase in exemption number for "low-use" equipment and simpler compliance options will help. As he points out, "The rule isn't perfect, but it now has a more realistic grasp of emissions' inventory."