EPA is on a Roll! RICE emission standards finalized…

image: diesel pump engine

RICE. On a sugar cane farm. (No, really!)

The US Environmental Protection Agency announced on January 14 that it has finalized revisions to standards for emissions from stationary engines that generate electricity and power equipment, better known as Reciprocating Internal Combustion Engines (“RICE”) in regulatory parlance.

The final rule amends the 2010 National Emission Standards for Hazardous Air Pollutants for Reciprocating Internal Combustion Engines (RICE) to address challenges to the 2010 rule by regulated industries. The 2010 rules separately addressed compression ignition engines, powered by diesel fuel, and spark ignition engines, usually powered by gasoline or natural gas. Both rules prompted petitions for reconsideration.

Among other changes, the amendments specify how the standards apply to emergency engines used for emergency demand response. Under the rules, any engine may operate without emissions limitations during an emergency. However, the emergency operating time during Level 2 energy emergency alerts – events with potential for blackouts – was limited to 15 hours per year. This 15-hour limit was viewed as insufficient to allow engines to be used in emergency demand response programs. Therefore, the amended provisions allow owners and operators to operate their engines as part of an emergency demand response program within the 100 operating hours separately allotted for maintenance and testing.


Briefly, other amendments include:

  • Replacing numerical emissions limits for existing area source, spark ignition engines above 500 horsepower in populated areas with requirements to install catalytic controls with an initial test and annual performance test checks of the catalyst and to equip the engine with a high temperature shutdown device or monitor the catalyst inlet temperature continuously;
  • Subjecting existing area source, spark ignition four-stroke engines above 500 hp that are not located in populated areas to management standards;
  • Allowing certain compression ignition engines scheduled for replacement due to state or local rules to meet management practices rather than emissions limits until January 1, 2015 (or 12 years after installation date, but not later than June 1, 2018);
  • Adding a 30 percent reduction of total hydrocarbon emissions as an alternative for demonstrating compliance with the formaldehyde emissions limit;
  • Subjecting existing area source, compression ignition, non-emergency engines above 300 hp on offshore drilling vessels to management practice requirements; and
  • Broadening the definition of “remote areas of Alaska” to allow wider use of the option to comply with management practices rather than emissions limits.

EPA also revised the New Source Performance Standards (NSPS) for stationary internal combustion engines to ensure consistency with the RICE NESHAP. Specifically, the amendment addresses how NSPS will apply to emergency engines used for demand response.

As with the boiler rule amendments, we will publish a web page detailing the requirements of the RICE emissions standard after completing our usual, exhaustive review. Look for a blog post here in the near future announcing the page. In the meantime, you can go to the EPA website (click here) for further information on the final RICE amendments.