EPA Proposes New Nitrogen Oxides Emissions Standards for Aircraft Engines

EPA Proposes New Nitrogen Oxides Emissions Standards for Aircraft Engines

On July 27, the Environmental Protection Agency issued a proposed rulethat would bring U.S. nitrogen oxides emission standards from newly certified and newly manufactured aircraft engines in line with the levels set by the International Civil Aviation Organization in 2004. 

As the EPA sets up a two-tier implementation schedule designed for new engines made after 2012, this new standard will not have a measurable effect on aircraft engine manufacturers because the engines in production already meet the specified standard.

This is the third rule-making that EPA has undertaken since the mid 1990’s to align U.S. regulatory policy with that of ICAO -- the UN body that regulates international civil aviation. After ICAO adopts a new standard and “recommended practice”, member nations must implement the standard at home. 

ICAO’s Committee on Aviation Environmental Protection (CAEP) is responsible for conducting technical work in the aviation environmental field. The committee undertakes research in many areas, including aircraft emissions, and makes recommendations to the ICAO Council on Proposed Standards And Recommended Practices. It has undertaken several rounds of aircraft emissions standards review, the most recent occurring in 2010. The goal of these standards is to progressively decrease the amount of harmful emissions from aircraft engines in order to minimize aviation’s impact on the environment and human health, and to improve local air quality.

Consistent with past actions, EPA’s most recent proposed rule-making would tighten nitrogen oxides emission standards from newly certified and newly manufactured aircraft engines to meet ICAO standards. The proposed rule has two tiers of stringency.  Tier 6 would require a 12 percent reduction in nitrogen oxides emissions based on the previous standard, and would be effectively immediately after the rule is finalized.  This is the standard set by CAEP in 2007.  The stricter standard is the Tier 8 standard, which would require a 15 percent reduction in nitrogen oxides emissions over 2007 levels.  This standard is based on the pending CAEP recommendations, and would apply to newly certified and newly manufactured aircraft engines 2013. 

ACI-World and ACI-NA generally support ICAO and EPA efforts to implement more stringent emissions standards from aircraft engines.  Nitrogen oxides are a precursor to tropospheric ozone, often referred to as ground-level ozone. Ozone can have negative impacts on human health. According to the EPA, breathing in high levels of tropospheric ozone can cause “chest pain, coughing, throat irritation, and congestion. It can worsen bronchitis, emphysema, and asthma. Ground-level ozone also can reduce lung function and inflame the linings of the lungs. Repeated exposure may permanently scar lung tissue”. Increased levels of ozone can also negatively affect the growth and health of nearby vegetation. In addition to health and ecosystem impacts, many airports are located in areas that do not meet National Ambient Air Quality Standards for ozone.  Non-attainment areas are obligated to take measures to reduce the ambient levels of pollutants, which can include restrictions on construction and development. 

Contact ACI-NA’s Katherine Prestonfor more information.

Short:

CAEP Falls Behind On Development of a Carbon Dioxide Standard For Aircraft

The International Civil Aviation Organization’s Committee on Aviation Environmental Protection was charged with developing a carbon dioxide certification standard for aircraft by 2013, but it appears they will not meet the deadline due to disagreement over the development of a carbon dioxide metric upon which the standard will be based. The disagreement between manufacturers and environmental groups (including the EPA) centers on how exactly to measure carbon emissions from aircraft (cruise fuel burn only, or climb, cruise, and descent), how to compare different aircraft models, and other considerations.  Opposing factions have sent their metrics proposals to a carbon dioxide working group that will meet in September.  The development of a carbon dioxide standard is now not likely to be completed until 2015 or later.