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AEROSOL PARTICLE COLLECTOR DESIGN STUDY

Description: A computational evaluation of a particle collector design was performed to evaluate the behavior of aerosol particles in a fast flowing gas stream. The objective of the work was to improve the collection efficiency of the device while maintaining a minimum specified air throughput, nominal collector size, and minimal power requirements. The impact of a range of parameters was considered subject to constraints on gas flow rate, overall collector dimensions, and power limitations. Potential improvements were identified, some of which have already been implemented. Other more complex changes were identified and are described here for further consideration. In addition, fruitful areas for further study are proposed.
Date: September 27, 2007
Creator: Lee, S & Richard Dimenna, R
Partner: UNT Libraries Government Documents Department

Site Environmental Report for 2009, Volume 2

Description: Volume II of the Site Environmental Report for 2009 is provided by Ernest Orlando Lawrence Berkeley National Laboratory as a supplemental appendix to Volume I, which contains the body of the report. Volume II contains the environmental monitoring and sampling data used to generate summary results of routine and nonroutine sampling at the Laboratory, except for groundwater sampling data, which may be found in the reports referred to in Chapter 4 of Volume I. The results from sample collections are more comprehensive in Volume II than in Volume I: for completeness, all results from sample collections that began or ended in calendar year (CY) 2009 are included in this volume. However, the samples representing CY 2008 data have not been used in the summary results that are reported in Volume I. (For example, although ambient air samples collected on January 6, 2009, are presented in Volume II, they represent December 2008 data and are not included in Table 4-2 in Volume I.) When appropriate, sampling results are reported in both conventional and International System (SI) units. For some results, the rounding procedure used in data reporting may result in apparent differences between the numbers reported in SI and conventional units. (For example, stack air tritium results reported as < 1.5 Bq/m3 are shown variously as < 39 and < 41 pCi/m3. Both of these results are rounded correctly to two significant digits.)
Date: August 19, 2010
Creator: Xu, Suying
Partner: UNT Libraries Government Documents Department

Evaluation of airflow patterns in 2706-T and 2706-TA

Description: The purpose of this study was to evaluate the adequacy of the current placement of fixed head air samplers and continuous air monitors (CAMs) in the 2706-T and 2706-TA Complex. The airflow study consisted of 6 configurations of facility HVAC and HEPA filtration equipment to determine impacts on CAM location. The results of this study provide recommendations based on guidance in DOE G 411.1-8 and NUREG-1400 for placement of fixed head air samplers or CAMS within 2706-T and 2706-TA.
Date: August 26, 1999
Creator: DEROSA, D.C.
Partner: UNT Libraries Government Documents Department

FLORIDA TOWER FOOTPRINT EXPERIMENTS

Description: The Florida Footprint experiments were a series of field programs in which perfluorocarbon tracers were released in different configurations centered on a flux tower to generate a data set that can be used to test transport and dispersion models. These models are used to determine the sources of the CO{sub 2} that cause the fluxes measured at eddy covariance towers. Experiments were conducted in a managed slash pine forest, 10 km northeast of Gainesville, Florida, in 2002, 2004, and 2006 and in atmospheric conditions that ranged from well mixed, to very stable, including the transition period between convective conditions at midday to stable conditions after sun set. There were a total of 15 experiments. The characteristics of the PFTs, details of sampling and analysis methods, quality control measures, and analytical statistics including confidence limits are presented. Details of the field programs including tracer release rates, tracer source configurations, and configuration of the samplers are discussed. The result of this experiment is a high quality, well documented tracer and meteorological data set that can be used to improve and validate canopy dispersion models.
Date: January 1, 2007
Creator: WATSON,T.B.; DIETZ, R.N.; WILKE, R.; HENDREY, G.; LEWIN, K.; NAGY, J. et al.
Partner: UNT Libraries Government Documents Department

THE REAL ISSUE WITH WALL DEPOSITS IN CLOSED FILTER CASSETTES - WHAT'S THE SAMPLE?

Description: The measurement of aerosol dusts has long been utilized to assess the exposure of workers to metals. Tools used to sample and measure aerosol dusts have gone through many transitions over the past century. In particular, there have been several different techniques used to sample for beryllium, not all of which might be expected to produce the same result. Today, beryllium samples are generally collected using filters housed in holders of several different designs, some of which are expected to produce a sample that mimics the human capacity for dust inhalation. The presence of dust on the interior walls of cassettes used to hold filters during metals sampling has been discussed in the literature for a number of metals, including beryllium, with widely varying data. It appears that even in the best designs, particulates can enter the sampling cassette and deposit on the interior walls rather than on the sampling medium. The causes are not well understood but are believed to include particle bounce, electrostatic forces, particle size, particle density, and airflow turbulence. Historically, the filter catch has been considered to be the sample, but the presence of wall deposits, and the potential that the filter catch is not representative of the exposure to the worker, puts that historical position into question. This leads to a fundamental question: What is the sample? This article reviews the background behind the issue, poses the above-mentioned question, and discusses options and a possible path forward for addressing that question.
Date: September 12, 2009
Creator: Brisson, M.
Partner: UNT Libraries Government Documents Department

Evaluation of a high-volume cascade particle impactor system

Description: From American Chemical Society 2nd joint conference on sensing of environmental pollutants; Washington, District of Columbia, USA (10 Dec 1973). Commercially available 20 cfm cascade impactors were evaluated under field sampling conditions for particle sampling bias caused by interstage losses and by non-wind direction sampler oriertation. An integrated sampler using an impactor and a winddirection self-orienting cowl attachment decreased particle sampling bias. (auth)
Date: September 1, 1973
Creator: Sehmel, G A
Partner: UNT Libraries Government Documents Department

The New York City Urban Dispersion Program March 2005 Field Study: Tracer Methods and Results.

Description: The Urban Dispersion Program March 2005 Field Study tracer releases, sampling, and analytical methods are described in detail. There were two days where tracer releases and sampling were conducted. A total of 16.0 g of six tracers were released during the first test day or Intensive Observation Period (IOP) 1 and 15.7 g during IOP 2. Three types of sampling instruments were used in this study. Sequential air samplers, or SAS, collected six-minute samples, while Brookhaven atmospheric tracer samplers (BATS) and personal air samplers (PAS) collected thirty-minute samples. There were a total of 1300 samples resulting from the two IOPs. Confidence limits in the sampling and analysis method were 20% as determined from 100 duplicate samples. The sample recovery rate was 84%. The integrally averaged 6-minute samples were compared to the 30-minute samples. The agreement was found to be good in most cases. The validity of using a background tracer to calculate sample volumes was examined and also found to have a confidence level of 20%. Methods for improving sampling and analysis are discussed. The data described in this report are available as Excel files. An additional Excel file of quality assured tracer data for use in model validation efforts is also available. The file consists of extensively quality assured BATS tracer data with background concentrations subtracted.
Date: October 1, 2005
Creator: Watson, T. B.; Heiser, J.; Kalb, P.; Dietz, R. N.; Wilke, R.; Wieser, R. et al.
Partner: UNT Libraries Government Documents Department

Statement of work for services provided by the Waste Sampling and Characterization Facility for Effluent Monitoring during Calendar Year 1996

Description: This report documents radionuclide air emissions from the Hanford Site and the resulting effective dose equivalent to any member of the public from those emissions. This report complies with the reporting requirements of the Code of Federal Regulations, Title 40, ``Protection of the Environment,`` Part 61, ``National Emissions Standards for Hazardous Air Pollutants,`` Subpart H, ``National Emission Standards for Emissions of Radionuclides Other Than Radon From Department of Energy Facilities`` (40 CFR 61 Subpart H) and Chapter 246-247 of the Washington Administrative Code (WAC 246-247).
Date: January 1, 1996
Creator: Gleckler, B. P.
Partner: UNT Libraries Government Documents Department

A continuous sampling air-ICP for metals emission monitoring

Description: An air-inductively coupled plasma (air-ICP) system has been developed for continuous sampling and monitoring of metals as a continuous emission monitor (CEM). The plasma is contained in a metal enclosure to allow reduced-pressure operation. The enclosure and plasma are operated at a pressure slightly less than atmospheric using a Roots blower, so that sample gas is continuously drawn into the plasma. A Teflon sampling chamber, equipped with a sampling pump, is connected to the stack that is to be monitored to isokinetically sample gas from the exhaust line and introduce the sample into the air-ICP. Optical emission from metals in the sampled gas stream is detected and monitored using an acousto-optic tunable filter (AOTF)--echelle spectrometer system. A description of the continuous sampling air-ICP system is given, along with some preliminary laboratory data for continuous monitoring of metals.
Date: September 19, 1999
Creator: Baldwin, D.P.; Zamzow, D.S.; Eckels, D.E. & Miller, G.P.
Partner: UNT Libraries Government Documents Department

296-B-13 stack monitoring and sampling system: Annual system assessment report

Description: This report presents the details of the annual system assessment of the air pollution monitoring and sampling system for the 296-13 stack at the Hanford site. Topics discussed include; system description, system status, system aging, spare parts considerations, long term maintenance plan, trends, and items requiring action.
Date: May 16, 1995
Creator: Ridge, T.M.
Partner: UNT Libraries Government Documents Department

Wind tunnel evaluation of the RAAMP sampler. Final report

Description: Wind tunnel tests of the Department of Energy RAAMP (Radioactive Atmospheric Aerosol Monitoring Program) monitor have been conducted at wind speeds of 2 km/hr and 24 km/hr. The RAAMP sampler was developed based on three specific performance objectives: (1) meet EPA PM10 performance criteria, (2) representatively sample and retain particles larger than 10 {micro}m for later isotopic analysis, (3) be capable of continuous, unattended operation for time periods up to 2 months. In this first phase of the evaluation, wind tunnel tests were performed to evaluate the sampler as a potential candidate for EPA PM10 reference or equivalency status. As an integral part of the project, the EPA wind tunnel facility was fully characterized at wind speeds of 2 km/hr and 24 km/hr in conjunction with liquid test aerosols of 10 {micro}m aerodynamic diameter. Results showed that the facility and its operating protocols met or exceeded all 40 CFR Part 53 acceptance criteria regarding PM10 size-selective performance evaluation. Analytical procedures for quantitation of collected mass deposits also met 40 CFR Part 53 criteria. Modifications were made to the tunnel`s test section to accommodate the large dimensions of the RAAMP sampler`s instrument case.
Date: November 1, 1994
Creator: Vanderpool, R.W. & Peters, T.M.
Partner: UNT Libraries Government Documents Department

Determining the Uncertainty Associated with Retrospective Air Sampling for Optimization Purposes

Description: NUREG 1400 contains an acceptable methodology for determining the uncertainty associated with retrospective air sampling. The method is a fairly simple one in which both the systemic and random uncertainties, usually expressed as a percent error, are propagated using the square root of the sum of the squares. Historically, many people involved in air sampling have focused on the statistical counting error as the deciding factor of overall uncertainty in retrospective air sampling. This paper looks at not only the counting error but also other errors associated with the performance of retrospective air sampling.
Date: October 3, 2003
Creator: Hadlock, D.J.
Partner: UNT Libraries Government Documents Department

Portable Monitor for Tritium in Air

Description: In the handling of tritium associated with heavy water moderator, there is a possibility that some of it, in the form of tritiated hydrogen or water vapor, may become airborne. An instrument is needed which will quantitatively measure tritium in air in order to protect personnel from the radiation hazard associated with tritium. This paper describes a portable air sampler developed to monitor concentrations of tritium in air between 4 x 10-5 and 1600 x 10-5 microcurie per cubic centimeter.
Date: January 16, 2003
Creator: Anthony, J.D.
Partner: UNT Libraries Government Documents Department

Low power, constant-flow air pump systems

Description: A rugged, yet small and lightweight constant-flow air pump system has been designed. Flow control is achieved using a novel approach which is three times more power efficient than previous designs. The resultant savings in battery size and weight makes these pumps ideal for sampling air on balloon platforms. The pump package includes meteorological sensors and an onboard computer that stores time and sensor data and turns the constant-flow pump circuit on/off. Some applications of these systems are also presented in this report.
Date: January 1, 1994
Creator: Polito, M. D. & Albert, B.
Partner: UNT Libraries Government Documents Department

Standard instrument calibration aerosol test system

Description: >A system for testing personal respirable'' samplers in a well characterized coal dust environment is described. Components of the system, contained in one cabinet, include a Wright Dust Feed mechanism, tritide charge neutralizer, aerosol chamber, electrostatic precipitator sampler, and a GCA Respirable Dust Monitor. in addition to air flow plumbing and controls. Employment of this test system to evaluate the performance of personal respirable'' particulate air sampling instruments required variations in aerosol mass concentration with respect to time and space to be less than plus or minus l0%. Up to four personal respirable'' dust samples can be simultaneously operated within the coal dust cloud. More than 80 tests of 3 or 4 samplers each showed that variation of total or respirable mass concentration is plus or minus 5% within the aerosol chamber. Aerosol aerodynamic size distribution measured with Andersen cascade impactors showed the dust cloud size to be stable within plus or minus 6% throughout periods of operation up to 8 h. (auth)
Date: September 1, 1973
Creator: Fairchild, C.I.; Ettinger, H.J.; Carson, G.A.; Gettemy, D.J.; Tillery, M.I. & Almich, B.
Partner: UNT Libraries Government Documents Department

Single point aerosol sampling: Evaluation of mixing and probe performance in a nuclear stack

Description: Alternative Reference Methodologies (ARMS) have been developed for sampling of radionuclide; from stacks and ducts that differ from the methods required by the US EPA. The EPA methods are prescriptive in selection of sampling locations and in design of sampling probes whereas the alternative methods are performance driven. Tests were conducted in a stack at Los Alamos National Laboratory to demonstrate the efficacy of the ARMS. Coefficients of variation of the velocity tracer gas, and aerosol particle profiles were determined at three sampling locations. Results showed numerical criteria placed upon the coefficients of variation by the ARMs were met at sampling stations located 9 and 14 stack diameters from flow entrance, but not at a location that is 1.5 diameters downstream from the inlet. Experiments were conducted to characterize the transmission of 10 {mu}m aerodynamic equivalent diameter liquid aerosol particles through three types of sampling probes. The transmission ratio (ratio of aerosol concentration at the probe exit plane to the concentration in the free stream) was 107% for a 113 L/min (4-cfm) an isokinetic shrouded probe, but only 20% for an isokinetic probe that follows the EPA requirements. A specially designed isokinetic probe showed a transmission ratio of 63%. The shrouded probe performance would conform to the ARM criteria; however, the isokinetic probes would not.
Date: December 31, 1994
Creator: Rodgers, J. C.; Fairchild, C. I.; Wood, G. O.; Ortiz, C. A.; Muyshondt, A. & McFarland, A. R.
Partner: UNT Libraries Government Documents Department

Observation of {sup 135}Xe with the PNNL ARSA System

Description: The automated radioxenon sampler-analyzer (ARSA) developed by PNNL and with funding and support form the DOE NN-20 CTBT research and development program, observed 9.1-hr {sup 135}Xe in a sample of New York City air obtained on April 4th, 1997. The report below briefly describes the ARSA system and the first ever reported measurement of the short-lived {sup 135}Xe from an automated radioxenon system.
Date: August 1, 1997
Creator: Reeder, P.L.; Bowyer, T.W. & Abel, K.H.
Partner: UNT Libraries Government Documents Department

Real-time mass spectrometry of individual airborne bacteria

Description: A method for the real-time detection of individual bacteria is described. Airborne bacteria and bacterial spores are directly sampled by laser ablation in an ion trap mass spectrometer with an atmospheric pressure inlet system. either positive or negative ion mass spectra can be obtained. Ions of a particular value of m/z can be further characterized by tandem mass spectrometry in the ion trap. Spectra averaged from several hundred individual bacteria of the same species appear to differ somewhat from spectra of bacteria of other species and to be readily distinguishable from spectra of nonbiological particles.
Date: August 1, 1997
Creator: Whitten, W.B.; Gieray, R.A.; Reilly, P.T.A.; Yang, M. & Ramsey, J.M.
Partner: UNT Libraries Government Documents Department

Headspace vapor characterization of Hanford waste tank 241-S-106: Results from samples collected on 06/13/96

Description: This report describes the analytical results of vapor samples taken from the headspace of the waste storage tank 241-S-106 (Tank S-106) at the Hanford Site in Washington State. The results described in this report were obtained to characterize the vapors present in the tank headspace and to support safety evaluations and tank farm operations. The results include air concentrations of selected inorganic and organic analytes and grouped compounds from samples obtained by Westinghouse Hanford Company (WHC) and provided for analysis to Pacific Northwest National Laboratory (PNNL). A summary of the inorganic analytes, permanent gases, and total non-methane organic compounds is listed in a table. The three highest concentration analytes detected in SUMMA{trademark} canister and triple sorbent trap samples are also listed in the same table. Detailed descriptions of the analytical results appear in the appendices.
Date: January 1, 1997
Creator: Evans, J.C.; Pool, K.H.; Thomas, B.L.; Olsen, K.B.; Fruchter, J.S. & Silvers, K.L.
Partner: UNT Libraries Government Documents Department

Determination of respirable mass concentration using a high volume air sampler and a sedimentation method for fractionation

Description: A preliminary study of a new method for determining respirable mass concentration is described. This method uses a high volume air sampler and subsequent fractionation of the collected mass using a particle sedimentation technique. Side-by-side comparisons of this method with cyclones were made in the field and in the laboratory. There was good agreement among the samplers in the laboratory, but poor agreement in the field. The effect of wind on the samplers` capture efficiencies is the primary hypothesized source of error among the field results. The field test took place at the construction site of a hazardous waste landfill located on the Hanford Reservation.
Date: December 31, 1995
Creator: Johnson, J.
Partner: UNT Libraries Government Documents Department