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Featured researches published by Henry D. Felton.


Journal of The Air & Waste Management Association | 2006

New York State urban and rural measurements of continuous PM2.5 mass by FDMS, TEOM, and BAM.

James J. Schwab; Henry D. Felton; Oliver V. Rattigan; Kenneth L. Demerjian

Abstract Field evaluations and comparisons of continuous fine particulate matter (PM2.5) mass measurement technologies at an urban and a rural site in New York state are performed. The continuous measurement technologies include the filter dynamics measurement system (FDMS) tapered element oscillating microbalance (TEOM) monitor, the stand-alone TEOM monitor (without the FDMS), and the beta attenuation monitor (BAM). These continuous measurement methods are also compared with 24-hr integrated filters collected and analyzed under the Federal Reference Method (FRM) protocol. The measurement sites are New York City (the borough of Queens) and Addison, a rural area of southwestern New York state. New York City data comparisons between the FDMS TEOM, BAM, and FRM are examined for bias and seasonality during a 2-yr period. Data comparisons for the FDMS TEOM and FRM from the Addison location are examined for the same 2-yr period. The BAM and FDMS measurements at Queens are highly correlated with each other and the FRM. The BAM and FDMS are very similar to each other in magnitude, and both are ∼25% higher than the FRM filter measurements at this site. The FDMS at Addison measures ∼9% more mass than the FRM. Mass reconstructions using the speciation trends network filter data are examined to provide insight as to the contribution of volatile species of PM2.5 in the FDMS mass measurement and the fraction that is likely lost in the FRM mass measurement. The reconstructed mass at Queens is systematically lower than the FDMS by ∼10%.


Journal of The Air & Waste Management Association | 2004

Semicontinuous PM2.5 sulfate and nitrate measurements at an urban and a rural location in New York: PMTACS-NY summer 2001 and 2002 campaigns.

Olga Hogrefe; James J. Schwab; Frank Drewnick; G. Garland Lala; Sarah B. Peters; Kenneth L. Demerjian; Kevin Rhoads; Henry D. Felton; Oliver V. Rattigan; Liaquat Husain; Vincent A. Dutkiewicz

Abstract Several collocated semicontinuous instruments measuring particulate matter with particle sizes ≤2.5 μm (PM2.5) sulfate (SO4 22−) and nitrate (NO3 −) were intercompared during two intensive field campaigns as part of the PM2.5 Technology Assessment and Characterization Study. The summer 2001 urban campaign in Queens, NY, and the summer 2002 rural campaign in upstate New York (Whiteface Mountain) hosted an operation of an Aerosol Mass Spectrometer, Ambient Particulate Sulfate and Nitrate Monitors, a Continuous Ambient Sulfate Monitor, and a Particle-Into-Liquid Sampler with Ion Chromato-graphs (PILS-IC). These instruments provided near realtime particulate SO4 2− and NO3 − mass concentration data, allowing the study of particulate SO4 2−/NO3 − diurnal patterns and detection of short-term events. Typical particulate SO4 2− concentrations were comparable at both sites (ranging from 0 to 20 μg/m3), while ambient urban particulate NO3 − concentrations ranged from 0 to 11 μg/m3 and rural NO3 − concentration was typically less than 1 μg/m3. Results of the intercomparisons of the semicontinu-ous measurements are presented, as are results of the comparisons between the semicontinuous and time-integrated filter-based measurements. The comparisons at both sites, in most cases, indicated similar performance characteristics. In addition, charge balance calculations, based on major soluble ionic components of atmospheric aerosol from the PILS-IC and the filter measurements, indicated slightly acidic aerosol at both locations.


Environmental Health | 2009

Surveillance of the short-term impact of fine particle air pollution on cardiovascular disease hospitalizations in New York State.

Valerie B. Haley; Thomas O. Talbot; Henry D. Felton

BackgroundStudies have shown that the effects of particulate matter on health vary based on factors including the vulnerability of the population, health care practices, exposure factors, and the pollutant mix.MethodsWe used time-stratified case-crossover to estimate differences in the short-term impacts of PM2.5 on cardiovascular disease hospital admissions in New York State by geographic area, year, age, gender, co-morbid conditions, and area poverty rates.ResultsPM2.5 had a stronger impact on heart failure than other cardiovascular diagnoses, with 3.1% of heart failure admissions attributable to short-term PM2.5 exposure over background levels of 5 ug/m3. Older adults were significantly more susceptible to heart failure after short-term ambient PM2.5 exposure than younger adults.ConclusionThe short-term impact of PM2.5 on cardiovascular disease admissions, and modifications of that impact, are small and difficult to measure with precision. Multi-state collaborations will be necessary to attain more precision to describe spatiotemporal differences in health impacts.


Aerosol Science and Technology | 2006

Field and Laboratory Evaluation of the Thermo Electron 5020 Sulfate Particulate Analyzer

James J. Schwab; Olga Hogrefe; Kenneth L. Demerjian; Vincent A. Dutkiewicz; Liaquat Husain; Oliver V. Rattigan; Henry D. Felton

The Thermo Electron Model 5020 Sulfate Particulate Analyzer is a recently commercialized instrument that provides continuous measurements of the sulfate component of ambient particulate matter. The technique uses a stainless steel rod placed inside a quartz oven to reduce the particle sulfate to sulfur dioxide; followed by pulsed fluorescence detection of the sulfur dioxide. Field and laboratory evaluations of a pre-production version of the analyzer are described as well as laboratory evaluations of the pre-production version and two production units. Laboratory tests concentrated on challenging the instruments with ammonium sulfate aerosol, but tests with sodium, potassium, and calcium sulfate are reported as well. The instrument performed very well in field and laboratory settings, reporting values that were highly correlated with continuous mass measurements in the lab, and 24-hour filters in the field. Conversion/detection efficiencies for ammonium sulfate in the laboratory, and for ambient sulfate aerosol at our rural site in Addison, New York, were both very close to 80%. Laboratory conversion efficiencies for calcium, sodium, and potassium sulfate salts ranged from 4% to 63%. These lower efficiencies for mineral-type sulfates will be an important consideration in areas with significant concentrations of sea salt or mineral dust sulfate, and less important for the high sulfate Eastern US which is dominated by ammonium sulfate.


Journal of The Air & Waste Management Association | 2004

Long-term field characterization of tapered element oscillating microbalance and modified tapered element oscillating microbalance samplers in urban and rural New York State locations.

James J. Schwab; John Spicer; Kenneth L. Demerjian; Jeffrey L. Ambs; Henry D. Felton

Abstract Long-term field comparisons of continuous and integrated filter measurements of mass concentrations of par-ticulate matter (PM) with an aerodynamic diameter less than or equal to 2.5 μm (PM2.5) were performed at rural and urban sites in New York State. Two versions of the continuous tapered element oscillating microbalance (TEOM) mass monitor are deployed at each site, in addition to Federal Reference Method filter samplers. Data are grouped into monthly averages to retain and demonstrate seasonal differences. Strong seasonal dependence is observed—the TEOM monitors with the heated sensors are biased systematically low with respect to the Federal Reference Method measurements during the cold season. For the rural site, the average bias for the sample equilibration system (SES)-equipped and standard TEOM monitors is 14 and 24%, respectively. At this location, the TEOM monitor measurements were biased low for all 34 months. For the urban site, the average bias for the SES and standard TEOM monitors is 8 and 18%, respectively. At this location, the TEOM monitor measurements are as likely to be biased high as low during the warm-season months. The hour averaged data from the two versions of the TEOM monitor are also compared, and also indicate that the SES-equipped version of the TEOM monitor captures 7-11% more PM2.5 mass at these locations.


Atmospheric Environment | 2006

Behavior of OH and HO2 in the winter atmosphere in New York City

Xinrong Ren; William H. Brune; Jingqiu Mao; Michael Mitchell; Robert Lesher; James B. Simpas; Andrew R. Metcalf; James J. Schwab; Chenxia Cai; Yongquan Li; Kenneth L. Demerjian; Henry D. Felton; Garry Boynton; Allen Adams; Jacqueline Perry; Yi He; Xianliang Zhou; Jian Hou


Journal of Geophysical Research | 2004

Aerosol chemical composition in New York state from integrated filter samples: Urban/rural and seasonal contrasts

James J. Schwab; Henry D. Felton; Kenneth L. Demerjian


Atmospheric Environment | 2006

Multi-year urban and rural semi-continuous PM2.5 sulfate and nitrate measurements in New York state : Evaluation and comparison with filter based measurements

Oliver V. Rattigan; Olga Hogrefe; Henry D. Felton; James J. Schwab; Utpal K. Roychowdhury; Liaquat Husain; Vincent A. Dutkiewicz; Kenneth L. Demerjian


Atmospheric Environment | 2017

Analysis of major air pollutants and submicron particles in New York City and Long Island

Mauro Masiol; Philip K. Hopke; Henry D. Felton; Brian P. Frank; Oliver V. Rattigan; M.J. Wurth; G.H. LaDuke


Atmospheric Environment | 2017

Source apportionment of PM2.5 chemically speciated mass and particle number concentrations in New York City

Mauro Masiol; Philip K. Hopke; Henry D. Felton; Brian P. Frank; Oliver V. Rattigan; M.J. Wurth; G.H. LaDuke

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Oliver V. Rattigan

New York State Department of Environmental Conservation

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Olga Hogrefe

State University of New York System

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Liaquat Husain

New York State Department of Health

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Vincent A. Dutkiewicz

New York State Department of Health

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Brian P. Frank

New York State Department of Environmental Conservation

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G.H. LaDuke

New York State Department of Environmental Conservation

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M.J. Wurth

New York State Department of Environmental Conservation

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