Measurements of Particle Number and Mass Concentrations and Size Distributions in a Tunnel Environment

Geller, Michael D.; Sardar, Satya; Phuleria, Harish C.; Fine, Philip M.; Sioutas, Constantinos

doi:10.1021/es050360s

Cited by 173 publications

(115 citation statements)

References 59 publications

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“…Some high EFs for HDDV have been reported in the past (1300−1440 mg kg −1 fuel ). 15,52 However, continued HDDV EF measurements at the same location over the subsequent decade demonstrated a significant reduction in the HDDV EF, 34,51 so that most are now consistent with those measured here. The similarity between the HDDV values during these chase events and during other studies lends confidence to the mixed fleet values measured in the present study and to the inferred LDGV values.…”

Section: Resultssupporting

confidence: 79%

“…The highest traffic flow is observed during morning and afternoon rush hours (∼ 120−130 vehicles min −1 ). This peak traffic volume is comparable to or higher than that of other near-roadway studies where BC emission factors have been measured, 14,34 while the fraction of HDDV at peak volume is generally intermediate to that of others. Although weekday and weekend values are averaged in Figure 2A, the subsequent analysis utilizes weekday, high-volume periods only.…”

Section: Resultssupporting

confidence: 58%

“…Other reported mean BC EFs tend to be for a somewhat lower count based HDDV fraction (<1%). 14,15,34 Results from that work fall well below even our median values of Figure 4.…”

Section: Resultsmentioning

confidence: 44%

See 2 more Smart Citations

Are Emissions of Black Carbon from Gasoline Vehicles Underestimated? Insights from Near and On-Road Measurements

Liggio

Gordon

Smallwood³

et al. 2012

Environ. Sci. Technol.

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Measurements of black carbon (BC) with a highsensitivity laser-induced incandescence (HS-LII) instrument and a single particle soot photometer (SP2) were conducted upwind, downwind, and while driving on a highway dominated by gasoline vehicles. The results are used with concurrent CO 2 measurements to derive fuel-based BC emission factors for real-world average fleet and heavy-duty diesel vehicles separately. The derived emission factors from both instruments are compared, and a low SP2 bias (relative to the HS-LII) is found to be caused by a BC mass mode diameter less than 75 nm, that is most prominent with the gasoline fleet but is not present in the heavy-duty diesel vehicle exhaust on the highway. Results from both the LII and the SP2 demonstrate that the BC emission factors from gasoline vehicles are at least a factor of 2 higher than previous North American measurements, and a factor of 9 higher than currently used emission inventories in Canada, derived with the MOBILE 6.2C model. Conversely, the measured BC emission factor for heavy-duty diesel vehicles is in reasonable agreement with previous measurements. The results suggest that greater attention must be paid to black carbon from gasoline engines to obtain a full understanding of the impact of black carbon on air quality and climate and to devise appropriate mitigation strategies.

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Section: Resultssupporting

confidence: 79%

Section: Resultssupporting

confidence: 58%

See 1 more Smart Citation

Are Emissions of Black Carbon from Gasoline Vehicles Underestimated? Insights from Near and On-Road Measurements

Liggio

Gordon

Smallwood³

et al. 2012

Environ. Sci. Technol.

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“…In developed countries, unimodal EC at MMAD of ∼0.1 µm was usually observed in vehicular exhaust in source studies (Kleeman et al 2000(Kleeman et al , 2008Geller et al 2005). In urban ambient environments, EC at MMAD less than 0.3 µm was frequently observed.…”

Section: Ec Size Distributionsmentioning

confidence: 99%

Modal Characteristics of Elemental and Organic Carbon in an Urban Location in Guangzhou, China

2009

Aerosol Science and Technology

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Carbonaceous matter is a major constituent in urban aerosols, especially in those collected in China. The size distributions of elemental carbon (EC) and organic carbon (OC) in the range of 0.01-18 µm were measured in an urban location in Guangzhou, China in July 2006. The EC size distribution in the accumulationmode size was characterized by three significant modes with mass median aerodynamic diameters (MMAD) of ∼0.15 µm, ∼0.40 µm, and ∼0.90 µm, with the second one being the most prominent and accounting for approximately half of the total EC mass. The coexistence of the first two accumulation modes in Guangzhou's urban atmosphere could be explained to be a result of emissions from vehicles operating at different loadings. The dominance of the EC accumulation mode at ∼0.40 µm has not often been reported in studies conducted in developed countries, but this observation is consistent with EC size distributions measured in a roadway tunnel in this region. This information is important when modeling the role of EC in modulating the radiative balance and investigating the health effects of EC. The third accumulation mode was postulated to be a result of in-cloud processing after emission. OC had the same size modes as EC but different mass distributions among the modes. The carbonaceous materials in the nucleation mode were dominated by OC. Among particles in the accumulation size range, the OC/EC ratio was higher in the third accumulation mode (MMAD: 0.90 µm) than in the first two accumulation modes, suggesting that in-cloud processing was an important pathway for accumulating OC mass during atmospheric processing of EC particles.

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“…Furthermore, the size ranges as well as the correction techniques used to account for dilution of the aerosol, vary widely. Most studies which calculated number emission factors were conducted in tunnel systems and the tunnel ventilation was used to calculate dilution conditions (Kirchstetter et al, 1999;Gidhagen et al, 2003;Kristensson et al, 2004;Geller et al, 2005;Ban-Weiss et al, 2010). Furthermore, different model systems were applied for the calculation of the dilution of the exhaust emissions (Jamriska and Morawska 2001;Corsmeier et al, 2005;Birmili et al, 2009;Wehner et al, 2009) or the NO x tracer method was used for the calculation of the dilution, like by Imhof et al (2005) and Wang et al (2010).…”

Section: Introductionmentioning

confidence: 99%

Size Resolved Particle Number Emission Factors of Motorway Traffic Differentiated between Heavy and Light Duty Vehicles

Nickel

Kaminski

Hellack

et al. 2013

Aerosol Air Qual. Res.

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It is well accepted that airborne particles can induce adverse health effects dependent on the source, composition, morphology and size. Studies indicate that ultrafine particles (diameter < 100 nm) are of specific importance. Therefore, upwind and downwind field measurements of particle number size distributions (14-750 nm), nitrogen oxides, PM 10 and PM 1 mass concentrations were performed to derive information on sources of those types of particles from motorways. The measurement stations were located at a motorway in a rural area with flat terrain and unhindered air flow situation. The mean particle number concentration was 20,900 #/cm 3 downwind and 3,400 #/cm 3 upwind of the motorway. The highest total particle number concentration at the downwind station was 141,000 #/cm 3 . About 90% of these particles were < 100 nm. The measured data were used to derive size-dependent emission factors (EF) using the NO x tracer method. This method is based on listed NO x EF (HBEFA, 2010). The average total particle number EF per vehicle was determined to be 3.5 × 10 14 particles/km. The average particle EF was 2.1 × 10 14 particles/km and 11.8 × 10 14 particles/km for light duty vehicles (LDV) and heavy duty vehicles (HDV). The higher EF for HDV is mainly caused by particles with diameters below 50 nm. The comparison of EF from the literature show the importance of the particle size range investigated. Especially particles at the lower size detection limit contribute to total particle number concentrations and hence determine the EF significantly. In the EURO V directive, particle number emission limits of 6 × 10 11 particles/km were set for diesel passenger cars. This value is defined for non-volatile particles > 23 nm. The EF for the given size range (> 23 nm) determined in this study were significantly higher with 1.0 × 10 14 for LDV.

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Measurements of Particle Number and Mass Concentrations and Size Distributions in a Tunnel Environment

Cited by 173 publications

References 59 publications

Are Emissions of Black Carbon from Gasoline Vehicles Underestimated? Insights from Near and On-Road Measurements

Are Emissions of Black Carbon from Gasoline Vehicles Underestimated? Insights from Near and On-Road Measurements

Modal Characteristics of Elemental and Organic Carbon in an Urban Location in Guangzhou, China

Size Resolved Particle Number Emission Factors of Motorway Traffic Differentiated between Heavy and Light Duty Vehicles

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