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Exhaust emissions of seventeen 2,3,7,8-substituted chlorinated dibenzo-p-dioxin/furan (CDD/F) congeners, tetra-octa CDD/F homologues, twelve WHO 2005 chlorinated biphenyls (CB) congeners, mono-nona CB homologues, and nineteen polycyclic aromatic hydrocarbons (PAHs) from a model year 2008 Cummins ISB engine equipped with aftertreatment including a diesel oxidation catalyst (DOC) and wall flow copper or iron urea selective catalytic reduction filter (SCRF) were investigated. These systems differ from a traditional flow through urea selective catalytic reduction (SCR) catalyst because they place copper or iron catalyst sites in close proximity to filter-trapped particulate matter. These conditions could favor de novo synthesis of dioxins and furans. The results were compared to previously published results of modern diesel engines equipped with a DOC, catalyzed diesel particulate filter (CDPF) and flow through urea SCR catalyst.

This paper summarizes the Heavy-Duty In-Use Testing (HDUIT) measurement allowance program for Particulate Matter Portable Emissions Measurement Systems (PM-PEMS). The measurement allowance program was designed to determine the incremental error between PM measurements using the laboratory constant volume sampler (CVS) filter method and in-use testing with a PEMS. Two independent PM-PEMS that included the Sensors Portable Particulate Measuring Device (PPMD) and the Horiba Transient Particulate Matter (TRPM) were used in this program. An additional instrument that included the AVL Micro Soot Sensor (MSS) was used in conjunction with the Sensors PPMD to be considered a PM-PEMS. A series of steady state and transient tests were performed in a 40 CFR Part 1065 compliant engine dynamometer test cell using a 2007 on-highway heavy-duty diesel engine to quantify the accuracy and precision of the PEMS in comparison with the CVS filter-based method.

The California Air Resources Board (CARB) adopted the Low Emission Vehicle (LEV) III regulations in January 2012, which lowered the particulate matter (PM) emissions standards for light-duty vehicles (LDVs) from 10 milligrams per mile (10 mg/mile) to 3 mg/mile beginning with model year (MY) 2017 and 1 mg/mile beginning with MY 2025. To confirm the ability to measure PM emissions below 1 mg/mile, a total of 23 LDVs (MY pre-2004 to 2009) were tested at CARB's Haagen-Smit Laboratory (HSL) (10 LDVs) and the United States Environmental Protection Agency's (US EPA) National Vehicle and Fuel Emissions Laboratory (NVEFL) (13 LDVs) using the federal test procedure (FTP) drive schedule. One LDV with PM emissions ranging from 0.6 - 0.8 mg/mile was tested at three CARB HSL test cells to investigate intra-lab and inter-lab variability. Reference, trip, and tunnel filter blanks were collected as part of routine quality control (QC) procedures.