MECA releases report on health impacts of ultrafine particulates
19 July 2013
The Manufacturers of Emission Controls Association (MECA) released a new report outlining the health impacts of ultrafine particulates (UFP) from cars, trucks, and off-road equipment and the benefits of reducing both the mass and number of particulate emissions through the use of advanced emission control technology—namely, particulate filters. The report—Ultrafine Particulate Matter and the Benefits of Reducing Particle Numbers in the United States—was prepared for MECA by experts at Gladstein, Neandross & Associates, including Senior Vice President Rich Kassel.
The report summarizes the current understanding of the potential adverse health impacts of UFPs; outlines the various control technologies that can be used to meet current and upcoming US EPA and California ARB emission standards; and documents the success story of using diesel particulate filters (DPF) to meet US and EU emission standards. The report indicates that a particle number (PN) measurement may offer a more robust unit than PM mass for determining compliance at very low particle emission levels. The report also quantifies the health benefits of the additional emission reductions that are realized when DPFs or gasoline particulate filters (GPFs) are used compared to only engine-based strategies.
In the report, MECA makes several recommendations for EPA and ARB to help achieve the maximum environmental and health benefits from their current and upcoming on-road and off-road emission standards:
- EPA and ARB should add a PN limit to its regulatory structure for mobile sources;
- EPA and ARB should consider a new set of heavy-duty diesel engine PM standards that would be equivalent in stringency to ARB’s future LEV III standards for light-duty vehicles;
- EPA should increase its in-use compliance monitoring of nonroad diesel engines that are certified without DPFs;
- EPA and ARB should coordinate activities to develop a methodology for measuring UFP emissions and particle numbers;
- Environmental agencies around the world should follow the U.S. lead and tighten evaporative emission limits as a way to control secondary organic aerosols; and
- Federal and state governments should play a greater role in accelerating the retirement or retrofitting of older, dirtier diesel engines and the introduction of cleaner diesel replacements.
“EPA and ARB have taken major strides over the past few years to make on-road and off-road vehicles and equipment cleaner and more fuel-efficient. However, there is growing concern in the public health community about the contribution of UFPs to the overall health impacts of PM. As this report shows, DPFs are capable of reducing both UFPs and total PM by well over 90%. In fact, DPFs are the only emission control technology currently able to consistently demonstrate high levels of reduction for all types of diesel PM that concern regulators—PM mass, ultrafine and nano-sized particles, overall particle numbers, and black carbon. It is clear that using DPFs, as well as GPFs, creates emission reductions beyond what is required by emissions standards—a bonus that translates directly into additional, quantifiable health benefits enjoyed by all Americans,” said MECA’s Executive Director, Joseph Kubsh.
Particle number emission limits have been included in the European emission regulations since the Euro 5/6 stage and will likely be a part of the future Stage V emission standards for nonroad engines. The introduction of the PN limits ensured that the DPF technology be used on all affected engine categories. In the United States, DPFs have been adopted on all light- and heavy-duty highway diesel engines to meet the respective mass-based PM standards. However, the Tier 4 nonroad emission standards—designed by the US EPA to force particulate filters—have been met in several categories of nonroad engines without the use of DPFs. This has been a source of concern for the US regulatory authorities. Further tightening of mass-based PM limits, a direction apparently favored in the United States, is not practical due to technical problems with the measurement of PM mass emissions at very low levels.
Source: MECA