Vehicle emission factors

Ingalls, M. N., L. R. Smith, and R. E. Kirksey, Measurement of On-Road Vehicle Emission Factors in the California South Coast Air Basin—Vol. I Regulated Emissions, Report No. SwRI-1604 from the Southwest Research Institute to the Coordinating Research Council, Atlanta, GA, June 1989 NTIS Document PB89220925. 

Robinson, N. F., W. R. Pierson, A. W. Gertler, and J. C. Sagebiel, Comparison of Mobile4.1 and Mobile5 Predictions with Measurements of Vehicle Emission Factors in Fort McHenry and Tuscarora Mountain Tunnels, Atmos. Environ., 30, 2257-2267 (1996). 

The calculation of the emission factor follows the method of Pierson (Pierson et al. 1996). The vehicle emission factor is the mass of specific pollutants produced in a unit kilometer. It can be determined from... 

To determine emission data based on real-world conditions, tunnel studies involving large numbers of cars are an approach of choice. Simultaneous determination of the pollutant concentrations at the entrance and exit of the tunnel as well as monitoring of traffic density and speed, temperature, air pressure and wind speed are used for calculation of vehicle emission factors representative for the respective car-fieet-composition. 

APRAC-3 contains the emission factor computation mcdiodology and treats traffic links in die primary network with low vehicle miles traveled as area sources. 

More detailed statistical analyses (chemical element balance, principal component analysis and factor analysis) demonstrate that soil contributes >50% to street dust, iron materials, concrete/cement and tire wear contribute 5-7% each, with smaller contributions from salt spray, de-icing salt and motor vehicle emissions (5,93-100). A list is given in Table VII of the main sources of the elements which contribute to street dust. 

The environment module (ENY) estimates transport emissions, fuel consumption and transport accidents based on vehicle-km-travelled (VKT) and emission factors, which are determined by the vehicle fleet structure. 

There has been a recent revival in interest in the use of ethanol-diesel fuel blends (E-diesel) in heavy-duty vehicles as a means to reduce petroleum dependency, increase renewable fuels use, and reduce vehicle emissions [27]. E-diesel blends containing 10-15% ethanol could be prepared via the use of additives. However, several fuel properties that are essential to the proper operation of a diesel engine are affected by the addition of ethanol to diesel fuel - in particular, blend stability, viscosity and lubricity, energy content and cetane number (increasing concentrations of ethanol in diesel lower the cetane number proportionately) [28]. Materials compatibility and corrosiveness are also important factors that need to be considered. 

Motor vehicle emissions account for another 15 . The measured lead concentration is divided among the refuse and motor vehicle factors. 

Similarly, increasing the on-road exhaust vehicle emissions by a factor of three in a Eulerian model was found to improve the agreement between predicted and observed concentrations of O-, and organics in the... 

A similar observation has been made in other countries where exhaust controls have been instituted. For example, vehicle emissions measurements made by remote sensing in Monterrey, Nuevo Leon, Mexico, showed that 1995 model years emitted 75% less CO, 70% less hydrocarbons, and 65% less NO compared to the pre-1991 vehicles without emission controls (Bishop et al., 1997). In Australia, emissions for pre-1986 vehicles were substantially larger than those from newer, catalyst-equipped cars, a factor of 4 for hydrocarbons, 2.5 for CO, and 2 for NO in addition, the reactivity (see Section 16.B) of the exhaust emissions... 

Fig. 5 NOx emission factors for Euro V trucks equipped with SCR and EGR systems. The example refers to articulated trucks in the 34-401 gross vehicle weight range. Source COPERT [29], original data derived from Hausberger et al. [30]...

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... 

Ban-Weiss GA, Luden MM, Kirchstetter TW, Harley RA (2009) Size-resolved particle number and volume emission factors for on-road gasoline and diesel motor vehicles. Downloaded at http //escholarship.org/uc/item/7k75r4bf... 

Bukowiecki N, Lienemann P, Hill M et al (2009) Real-world emission factors for antimony and other brake wear related trace elements size-segregated values for light and heavy duty vehicles. Environ Sci Technol 43 8072-8078... 

The emission inventory of dioxin-like compounds in South Korea was determined during two preliminary studies (KMOE, 2001, 2002a). For emission factors, the preliminary study (KMOE, 2001) adopted measured values for waste incinerators and the values of UNEP chemicals Toolkit (UNEP Chemicals, 2001) for the other sources. Estimated PCDDs/DFs emission in 1999 ranged from 1163 to 1595 g I-TEQ yr-1 due to uncertainties in emission factors and activities (Table 2.6). Besides the preliminary estimate, since the late 1990s extensive measurements of PCDDs/ DFs have been performed at waste incinerators and the emission data by 2004 had been compiled for 1800 incinerators. Moreover, nationwide industrial sources have been investigated every year since 2001 34 fer-rous/non-ferrous metal production factories in 2001, 114 non-ferrous metal and mineral production factories in 2002, 73 chemical/energy/ landfill factories and crematories in 2003, and 63 municipal wastewater treatment plants and 9 types of vehicles in 2004. By 2005, measurements of total dioxin emissions had been made on 288 industrial sources. Based on these measurements, KMOE made the first official estimate of PCDDs/DFs emission in South Korea. It has been estimated that the total PCDDs/DFs emission was 1021 g I-TEQ yr-1 in 2001 (KMOE website) (Table 2.6). This emission was approximately 62% of that... 

While all pertinent factors that affect the distribution of vehicular emissions cannot be taken into account, emissions rates may still be represented with suflBcient accuracy to merit inclusion in an urban airshed model. For simplicity a vehicle emissions inventory can be divided into two parts ... 

Zweidinger RB. 1982. Emission factors from diesel and gasoline powered vehicles Correlation with the Ames test. Dev Toxicol Environ Sci 10 83-96. 

Quantitative measures of emissions are emissions factors and emission rates. A source emission factor is typically defined as the amount of a chemical species, mass, particle number, etc. emitted per unit mass of fuel burned or per defined task performed [3]. The former is often referred to as a mass-based emission factor and has a unit such as grams per kilogram. The latter can be called a task-based emission factor. The unit of the task-based emission factor depends on the definition of the tasks. For example, a task can be the number of cigarettes smoked or a certain distance driven by a motor vehicle and thus the units may be grams per cigarette or grams per kilometre, respectively. The emission rate, on the other hand, is the amount of a chemical species, mass, particle number, etc. emitted by the source per unit time. For example, emissions from stoves are usually characterised in terms of emission factors. Similarly, re-entrainment of settled dust to the air is represented by resuspension rates. Emission factors and emission rates vary significantly... 

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