AAAR 35th Annual Conference October 17 - October 21, 2016 Oregon Convention Center Portland, Oregon, USA
Abstract View
Comprehensive Characterization of Vehicle Emissions in Ft. McHenry Tunnel
ANDREY KHLYSTOV, David Campbell, Mark McDaniel, Chiranjivi Bhattarai, Desert Research Institute
Abstract Number: 578 Working Group: Urban Aerosols
Abstract Vehicular traffic emits large quantities of gaseous and particulate air pollutants, affecting air quality and human health. To mitigate the negative effects of traffic, several controls have been introduced in recent years to reduce emissions from both heavy-duty (HD) and light-duty (LD) vehicles. We will present results of a mobile source emission study aimed to investigate real life effectiveness of emission controls and to update profiles of traffic-emitted air pollutants. The study was conducted during two one-week-long campaigns, one in winter (February 2015) and one in summer (August 2015), in the Ft. McHenry tunnel in Baltimore, MD, USA. The tunnel passes under the Baltimore Harbor and carries traffic of Interstate 95, the main highway on the East Coast of the U.S. It is a four-bore 2.2 km tunnel, with two lanes per bore. HD vehicles are limited to the right-hand bore, while LD vehicles are allowed in all bores. The posted speed limit is 55 mph. The daily traffic volume is approximately 127,000 vehicles per day. The sampling was conducted at the exit of each eastbound bore and in the east ventilation building that supplies air to the eastbound bores. We will present fleet-averaged fuel-based emission factors (EFs) for criteria and non-criteria gaseous and particulate pollutants measured during this study, including: carbon monoxide and oxides of nitrogen, PM2.5, organic and elemental carbon, volatile organic compounds, carbonyls, gas- and particle-phase polycyclic aromatic hydrocarbons, alkanes and cycloalkanes, alkenes, hopanes, steranes, and nitro-PAHs. The dependence of EFs on fleet composition, fuels, and ambient conditions will be evaluated. The effect of temperature on evaporative emissions, as derived from winter and summer measurements, will also be discussed.