Tag Archives: nitrogen oxides

Berkeley Lab Study Assesses Residential Cooking Exhaust Hoods’ Ability to Vent Pollutants

Cooking exhaust hoods designed for home kitchens vary widely in their ability to capture and vent away the air pollutants generated by the gas burners on cook stoves, according to a study by two Lawrence Berkeley National Laboratory (Berkeley Lab) scientists. Of seven representative devices they tested, the capture efficiency varied from less than 15 percent to more than 98 percent.

The study, by Woody Delp and Brett Singer of Berkeley Lab’s Environmental Energy Technologies Division, measured their pollutant capture efficiency, sound level generated by their fans, and airflow. Cooking exhaust hoods vent such pollutants as carbon monoxide, nitrogen oxides, formaldehyde, and fine particulates such as soot generated during cooking. (more…)

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Diesel Technologies Drastically Cut Emissions in Real-World Conditions

New research from North Carolina State University shows that federal requirements governing diesel engines of new tractor trailer trucks have resulted in major cuts in emissions of particulate matter (PM) and nitrogen oxides (NOx) – pollutants that have significant human health and environmental impacts.

“These requirements for new emission control technologies have increased costs for truck owners and operators, and we wanted to know whether there was any real benefit,” says Dr. Chris Frey, professor of civil, construction and environmental engineering at NC State and co-author of a paper describing the research. “We found that there is a huge reduction in both PM and NOx emissions.” (more…)

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Acid Rain Study Show Substantial Decreases, But More Progress is Needed

WASHINGTON, D.C. — Measurable improvements in air quality and visibility, human health, and water quality in many acid-sensitive lakes and streams, have been achieved through emissions reductions from electric generating power plants and resulting decreases in acid rain. These are some of the key findings in a report to Congress by the National Acid Precipitation Assessment Program, a cooperative federal program.

The report shows that since the establishment of the Acid Rain Program, under Title IV of the 1990 Clean Air Act Amendments, there have been substantial reductions in sulfur dioxide (SO2) and nitrogen oxides (NOx) emissions from power plants that use fossil fuels like coal, gas and oil, which are known to be the primary causes of acid rain. As of 2009, emissions of SO2 and NOx declined by about two-thirds relative to levels in the 1990s. These emissions levels declined even further in 2010, according to recent data compiled by the U.S. Environmental Protection Agency. (more…)

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