Emission factors standards

In addition, the PMio NAAQS will continue to place emphasis on quantifying and reducing particulate emissions in the less than 10- Im particle-size range. Particle size-specific emission factors have been developed for many sources, and size-specific emission standards have been developed in a number of states. These standards are addressing concerns related to HAP emissions of hea y metals, which are generaUy associated with the submicron particles. 

In addition to chemicals covered under TRI, many other chemicals are released. For example, the EPA Office of Air Quality Planning and Standards has compiled air pollutant emission factors for determining the total air emissions of priority pollutants (e.g., VOCs, SO, NO, CO, particulates, etc.) from many refinery sources. The EPA Office of Aerometric Information Retrieval System (AIRS) contains a wide range of information related to stationary sources of air pollution, including the emissions of a number of air pollutants which may be of concern within a particular industry. With the exception of volatile organic compounds (VOCs), there is little overlap with the TRI chemicals reported above. 

EPA, 1997. U.S. EPA, Office of Air Quality Planning and Standards, "Compilation of Air Pollutant Emission Factors. Volume I, Fifth Edition, Research Triangle Park, NC., October. 

In table 1 some results from this study (2) of odour reduction are presented. The thresholds are mean values expressed as log dilution factors. Standard deviations are calculated on the averages of doubled ED-50 values, each value based on the reports of six observers at a time. As can be seen, incorporation of the manure largely reduced the emission of odour from the field. This mainly concerns the injection techniques, which in some cases reduced the odour to the background level. Conventional tillage implements such as a plow or a disc harrow also reduced the odour emission considerably. 

Four types of emissions related to distance from a sampling site are compiled using standard emissions factors where applicable. Pace investigated many other variables in multiple linear regressions with TSP but found these to be the significant ones. 

In 1970, new efforts were underway to solve Portland s suspended particulate problem. Early efforts relied on available emission factors and industrial source testing, as a basis for the emission Inventory. The inventory was then used, with a proportional rollback model, as a basis for the new strategy. New industrial controls were Installed which resulted in a 60,000 tons per year region-wide reduction in industrial emissions. Although progress toward cleaner air was made, air quality standard violations caused by then unknown sources continued and modeling efforts failed to account for over one-half of the particulate mass. 

TABLE 16.7 California s Low-Emission Vehicle Standards for Passenger Cars and Light-Duty Trucks Introduction of Ozone Reactivity Adjustment Factors"... 

The similar emission factors reported for mercury and nickel (28), even though the latter is approximately 1000 times more concentrated in coal, probably reflect volatility differentials. Volatile elements commonly considered the most hazardous are Be, F, As, Se, Cd, Pb, and Hg (4). Volatility and dispersion are associated with multimedia contamination (7) which necessitated the determination of likely absorption through inhalation and ingestion when national ambient standards for mercury were developed (29). 

In spite of the new vehicle emission EUROx regulations, 20% of Europe s urban population is also living in areas where the atmospheric concentrations of nitrogen dioxide (N02) exceed established air quality standards [18]. This is due to several factors related to the diesel-powered cars [19] (1) their increasing market penetration across Europe [20] (2) the NO emission factors of diesel cars exceed the emission levels as established during the type approval of these vehicles in the laboratory [19, 21-25] and (3) the fraction of N02 in the NO emissions of diesel... 

China alone will contribute a quarter of the increase in C02 emissions or 3.6 billion tons, bringing its total emissions to 6.7 billion tons per year in 2030. However, Chinese emissions will still be well below those of the USA. A projected increase in fossil fuel consumption is largely responsible for fast-paced growth in C02 emissions. Of the fossil fuels, coal and oil account currently for the major part of the total energy-related C02 emissions. Factors such as population growth, rising personal incomes, improved standards of living, and further industrialization are expected to have a... 

The CEN/TC 295 draft standard prEN 13240 [1] is based on measurements of efficiency and flue gas emissions at a nominal burning rate. The emission factors are based on concentration measurements of the pollutants in the due gas. The efficiency is calculated indirectly by the flue loss method taking into account the thermal due gas losses (sensible heat) and the chemical losses (combustible gases, here as carbon monoxide, CO). 

Fig. 2 Comparison of the emission factors determined in accordance with ISO/DIS and CEN/prEN test standards based on heat output with a continuous burning appliances.

The flue gas emissions are indicated as concentration based on a given value of oxygen in the exhausts (e.g. vol 13%) and as emission factors as mass per unit fuel based on dry with ash. The calculations of the gas concentration figures are based on the CEN/prEN test standards e.g. 13240. The calculations for the emission factors arc new and need to be defined. 

Specific emission rate Product specific rate describing the mass of a volatile organic compound emitted from a product per unit time at a given time from the start of the test. The area-specific emission rate, SERg, is used in the standard. Several other specific emission rates can be defined according to different requirements, for example, length-specific emission rate, SERi, volume-specific emission rate, SER, and unit-specific emission rate, SER,. The term area-specific emission rate is sometimes used in parallel with the term emission factor. 

In 2009, the European Union introduced a particle number limit to its Euro 5/6 emission standard for light-duty diesel vehicles. This is the first particle number standard introduced anywhere in the world. Particle number concentrations will be measured according to the PMP procedure, and emission factors will be limited to 5 X 10 km . Motor vehicle emissions often contain large numbers of volatile and semivolatile nanoparticles that are produced after emission from the tailpipe. The formation mechanisms of these nanoparticles, their associated health effects and concentrations are topics that are not well-understood as a result, the issue of whether these nanoparticles should be included in particle number standards has been the subject of much controversy in the recent past. In order to avoid this... 

USEPA (2009) Particulate Matter National Ambient Air Quality Standards scope and methods plan for health risk and exposure assessment. Office of Air Quality Planning and Standards, U.S. Environmental Protection Agency. Research Triangle Park, NC 27711 Viana M, Amato F, Alastuey A et al (2009) Chemical tracers of particulate emissions from commercial shipping. Environ Sci Technol 43 7472-7477 Wallace LA, Emmerich SJ, Howard-Reed C (2004) Source strengths of ultrafine and fine particles due to cooking with a gas stove. Environ Sci Technol 38 2304-2311 Wardoyo AYP, Morawska L, Ristovski ZD et al (2006) Quantification of particle number and mass emission factors from combustion of Queensland trees. Environ Sci Technol 40 5696-5703... 

Presentations and discussion in this session fully recognized that data bases on PAH either do not exist or do not offer sufficient quality. Calculation of emission factors was difficult because of a lack of homogeneous data. Risk assessment of the use of diesel fuel in transportation is nearly impossible in the U.S. given the paucity of epidemiological data related to PAH and their derivatives. In the same way, the basic question formulated at the beginning of the workshop whether polycyclics increased in exhaust as a function of the concentration of aromatics in the fuel, remains controversial. Standardization of sampling and analysis data and units is necessary before data bases can be built. 

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