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Aerosol deposition and losses in two alpha air monitors

Description: We assessed particle deposition and loss occurring in two alpha-air monitors: an Eberline Alpha-3 Continuous Air Monitor (CAM) and a working-area transuranic aerosol monitor (WOTAMS). We investigated the dependence of particle size on losses in the sampling inlets and the real-time alpha detector areas for both instruments. We determined the uniformity of particle deposition on the filter to ascertain the effectiveness of the detector and collection-filter configuration. Results indicate that particle losses are a strong function of particle size in the CAM unit, with a 44% loss occurring for 6-..mu..m-diameter aerosols and a 0.3% loss for 0.6-..mu..m-diameter aerosols. Losses in the WOTAMS were less than 1% for particle diameters in the 0.6-to-7 ..mu..m range.
Date: November 27, 1985
Creator: Biermann, A.H. & Sawyer, S.R.
Partner: UNT Libraries Government Documents Department

Evaluation of permanently charged electrofibrous filters

Description: These studies showed that loading the permanently charged filters with captured aerosols will lead to a neutralization of the filter charge. The transfer from the captured aerosol to the fiber surface and the subsequent neutralization of fiber charge. The increased efficiency is due to the additional mechanical capture by the particle deposits. The minimum efficiency obtained during the loading of solid aerosols is determined by the aerosol charge, with highly charged aerosols producing a lower minimum. Permanently charged filters lose their fiber charge when exposed to organic solvents or ionic water solutions. The fiber charge neutralization was minimized by coating the charged fibers with a polymer. Several different coating techniques were examined. Unfortunately, preventing the neutralization of fiber charge is not sufficient to prevent a deterioration of filter efficiency.
Date: October 18, 1982
Creator: Biermann, A.H.; Lum, B.Y. & Bergman, W.
Partner: UNT Libraries Government Documents Department

LLNL NESHAPs 1995 annual report

Description: This annual report is prepared pursuant to the National Emissions Standards for Hazardous Air Pollutants (NESHAPs) 40 CFR Part 61, Subpart H; Subpart H governs radionuclide emissions to air from Department of Energy (DOE) facilities. NESHAPs limits the emission of radionuclides to the ambient air from DOE facilities to levels resulting in an effective dose equivalent (EDE) of 10 mrem to any member of the public. This document contains the EDEs for the Lawrence Livermore National Laboratory (LLNL) site-wide maximally exposed members of the public from 1995 operations.
Date: June 1, 1996
Creator: Gallegos, G.M.; Harrach, R.J.; Biermann, A.H. & Tate, P.J.
Partner: UNT Libraries Government Documents Department

Attachment of radon progeny to cigarette-smoke aerosols

Description: The daughter products of radon gas are now recognized as a significant contributor to radiation exposure to the general public. It is also suspected that a synergistic effect exists with the combination cigarette smoking and radon exposure. We have conducted an experimental investigation to determine the physical nature of radon progeny interactions with cigarette smoke aerosols. The size distributions of the aerosols are characterized and attachment rates of radon progeny to cigarette-smoke aerosols are determined. Both the mainstream and sidestream portions of the smoke aerosol are investigated. Unattached radon progeny are very mobile and, in the presence of aerosols, readily attach to the particle surfaces. In this study, an aerosol chamber is used to contain the radon gas, progeny and aerosol mixture while allowing the attachment process to occur. The rate of attachment is dependent on the size distribution, or diffusion coefficient, of the radon progeny as well as the aerosol size distribution. The size distribution of the radon daughter products is monitored using a graded-screen diffusion battery. The diffusion battery also enables separation of the unattached radon progeny from those attached to the aerosol particles. Analysis of the radon decay products is accomplished using alpha spectrometry. The aerosols of interest are size fractionated with the aid of a differential mobility analyzer and cascade impactor. The measured attachment rates of progeny to the cigarette smoke are compared to those found in similar experiments using an ambient aerosol. The lowest attachment coefficients observed, {approximately}10{sup {minus}6} cm{sup 3}/s, occurred for the ambient aerosol. The sidestream and mainstream smoke aerosols exhibited higher attachment rates in that order. The results compared favorably with theories describing the coagulation process of aerosols.
Date: May 1, 1995
Creator: Biermann, A.H. & Sawyer, S.R.
Partner: UNT Libraries Government Documents Department

LLNL NESHAPs Project 1994 Annual Report

Description: The NESHAPs standared in 40 CFR part 61, Subpart H limites the emission of radionuclides to the ambient air from DOE facilities to levels resulting in an annual effective dose equivalent (EDE) of 10 mrem to any member of the public. The EDEs to the LLNL site-wide maximally exposed member of the public from 1994 operations were: Livermore 0.065 mrem; site 300 - 0.081 mrem. A complete LLNL-wide radionuclide-inventory update was conducted for 1994. Inventory and site-specific meteorological data, together with results from continuous-monitoring systems, were used as inputs to the EPA-approved CAP88-PC air-dispersion/dose-assessment model to calculate the reported EDEs.
Date: June 1, 1995
Creator: Surano, K.A.; Biermann, A.H. & Harrach, R.J.
Partner: UNT Libraries Government Documents Department

Field evaluation of prototype electrofibrous filters

Description: New prototype electrofibrous filters were designed, built and evaluated in laboratory tests and in field installations. Two prototypes were designed for use in nuclear ventilation ducts as prefilters to HEPA filters. One prototype is designed to be a permanent component of the ventilation system while the other is a disposable unit. The disposable electrofibrous prefilter was installed in the exhaust stream of a glove box in which barrels of uranium turnings are burned. Preliminary tests show the disposal prefilter is effectively prolonging the HEPA filter life. An earlier prototype of the rolling prefilter was upgraded to meet the increased requirements for installation in a nuclear facility. This upgraded prototype was evaluated in the fire test facility at LLNL and shown to be effective in protecting HEPA filters from plugging under the most severe smoke conditions. The last prototype described in this report is a recirculating air filter. After demonstrating a high performance in laboratory tests the unit was shipped to Savannah River where it is awaiting installation in a Pu fuel fabrication facility. An analysis of the particulate problem in Savannah River indicates that four recirculating air filter will save $172,000 per year in maintenance costs.
Date: September 30, 1982
Creator: Kuhl, W.D.; Bergman, W.; Biermann, A.H. & Lum, B.Y.
Partner: UNT Libraries Government Documents Department

Evaluation of prototype electrofibrous filters for nuclear-ventilation ducts

Description: Two prototypes electrofibrous filters were designed, built and evaluated in laboratory tests and in field installations. These prototypes were designed for use in nuclear ventilation ducts as prefilters to HEPA filters. One prototype is designed to be a permanent component of the ventilation system while the other is a disposable unit. The disposable electrofibrous prefilter was installed in the exhaust stream of a glove box in which barrels of uranium turnings are burned. Preliminary tests show the disposable prefilter is effectively prolonging the HEPA filter life.
Date: December 2, 1982
Creator: Bergman, W.; Kuhl, W.D.; Biermann, A.H.; Johnson, J.S. & Lum, B.Y.
Partner: UNT Libraries Government Documents Department

Electrostatic air filters generated by electric fields

Description: This paper presents theoretical and experimental findings on fibrous filters converted to electrostatic operation by a nonionizing electric field. Compared to a conventional fibrous filter, the electrostatic filter has a higher efficiency and a longer, useful life. The increased efficiency is attributed to a time independent attraction between polarized fibers and charged, polarized particles and a time dependent attraction between charged fibers and charged, polarized particles. The charge on the fibers results from a dynamic process of charge accumulation due to the particle deposits and a charge dissipation due to the fiber conductivity.
Date: January 27, 1981
Creator: Bergman, W.; Biermann, A.H.; Hebard, H.D.; Lum, B.Y. & Kuhl, W.D.
Partner: UNT Libraries Government Documents Department

A transuranic aerosol measurement system: Preliminary results

Description: We have completed the design, fabrication, and assembly of a computer-based prototype system for the measurement of transuranic aerosols in the workplace and environment. This system (called WOTAMS for Workplace Transuranic Aerosol Measurement System) incorporates two detectors: (1) an in-line solid-state alpha detector that sends out an alarm the moment a transuranic release occurs, and (2) an in-vacuum detector that increases off-line-analysis sensitivity. The in-line sensitivity of the system is better than 5.0 MPC-h, and the in-vacuum sensitivity exceeds 0.5 MPC-h. 5 refs., 8 figs., 1 tab.
Date: October 1, 1986
Creator: Prevo, C.T.; Kaifer, R.C.; Rueppel, D.W.; Delvasto, R.M.; Biermann, A.H. & Phelps, P.L.
Partner: UNT Libraries Government Documents Department

LLNL NESHAP's 1999 Annual Report

Description: This annual report is prepared pursuant to the National Emissions Standards for Hazardous Air Pollutants (NESHAPs) 40 CFR Part 61, Subpart H; Subpart H governs radionuclide emissions to air from Department of Energy (DOE) facilities. NESHAPs limits the emission of radionuclides to the ambient air from DOE facilities to levels resulting in an annual effective dose equivalent (EDE) of 10 mrem (100 {micro}Sv) to any member of the public. The EDEs for the Lawrence Livermore National Laboratory (LLNL) site-wide maximally exposed members of the public from 1999 operations are summarized.
Date: June 1, 2000
Creator: Gallegos, G.; Biermann, A.H.; Harrach, R.J.; Bertoldo, N.A.; Berger, R.L. & Surano,K.A.
Partner: UNT Libraries Government Documents Department

Electrofibrous prefilters for use in nuclear ventilation systems

Description: We have established a comprehensive program for the US Department of Energy to develop electrofibrous prefilters to extend the life of High Efficiency Particulate Air (HEPA) filters that are used in the nuclear industry. We have selected the electrofibrous filter because, compared to the mechanical fibrous filter, it has a higher efficiency and longer lifetime. Two different electrofibrous filters have been developed for use in nuclear ventilation systems. One prototype is a stationary prefilter while the other is a rolling prefilter. Both prefilters use the same basic filtering technique in which a fibrous filter medium is sandwiched between a high voltage electrode and a ground electrode, both electrodes having a sufficient open area to offer minimum air resistance. The applied voltage on the electrodes generates an electric field that polarizes the filter fibers, which then attract suspended particles via electrostatic forces. The filter media and electrodes have been pleated to provide a sufficiently long particle residence time. The special requirement of protecting the HEPA filter from a high concentration of smoke aerosols during fire conditions led to the development of the rolling, electrofibrous prefilter. We established the feasibility of this concept in a series of tests using commercially available rolling prefilters that were modified for removing smoke aerosols. Although the rolling prefilter concept is not a cost effective measure for the sole purpose of protecting HEPA filters from smoke aerosols, it became cost effective when used primarily for protecting the HEPA filters from normal production aerosols. The same piece of equipment is then used for both normal operating conditions as well as emergency fire conditions. Several prototype electrofibrous rolling prefilters were designed, built and evaluated. The filter evaluations were conducted using NaCl and DOP aerosols as well as smoke aerosols.
Date: February 19, 1981
Creator: Bergman, W.; Kuhl, W.D.; Russell, W.L.; Taylor, R.D.; Hebard, H.D.; Biermann, A.H. et al.
Partner: UNT Libraries Government Documents Department

Site Annual Environmental Report for 1997 - Data Supplement

Description: This Data Supplement to the Lawrence Livermore National Laboratory's (LLNL's) annual Environmental Report 1997 (called Volume 2 in previous years) was prepared for the U.S. Department of Energy. The main volume is intended to provide all information on LLNL's environmental impact and compliance activities that is of interest to most readers. The Data Supplement supports main volume summary data and is essentially a detailed data report that provides individual data points, where applicable. Some summary data are also included in the Data Supplement, and more detailed accounts are given of sample collection and analytical methods. Not all of the data in the Data Supplement tables have been reduced to the proper number of significant figures; however, summary data in both volumes are expressed using the proper number of significant figures. The two volumes are organized in a parallel fashion to aid the reader in cross-referencing between them. This supplement includes more detailed information to support the nine chapters in the main volume that cover monitoring of air, air effluent, sewerable water, surface water, ground water, soil and sediment, vegetation and foodstuff, environmental radiation, and quality assurance. The other four chapters in the main volume have no supporting information in the Data Supplement. As in our previous annual reports, data are presented in Systeme International (SI) units. In particular, the primary units used for radiological results are becquerels and sieverts for activity and dose, with curies and rem used secondarily (1 Bq = 2.7 x 10{sup {minus}11} Ci; 1 Sv = 100 rem).
Date: September 1, 1998
Creator: Biermann, A.H.; Althouse, P.E.; Brandstetter, E.R.; Christofferson, E.C.; Fields, B.C.; Gallegos, G.M. et al.
Partner: UNT Libraries Government Documents Department

Site Annual Environmental Report for 1997 - Executive Summary

Description: The Environmental Report 1997 is prepared for the U.S. Department of Energy (DOE), as required by DOE Order 5400.1 and DOE Order 231.1, by the Environmental Protection Department (EPD) at the Lawrence Livermore National Laboratory (LLNL). The results of LLNL's environmental monitoring and compliance effort and an assessment of the impact of LLNL operations on the environment and the public are presented in this publication.
Date: September 1, 1998
Creator: Biermann, A.H.; Althouse, P.E; Brandstetter, E.R.; Christofferson, E.C.; Fields, B.C.; Gallegos, G.M. et al.
Partner: UNT Libraries Government Documents Department

Site Annual Environmental Report for 1997 (SAER)

Description: The Environmental Report 1997 is prepared for the U.S. Department of Energy (DOE), as required by DOE Order 5400.1 and DOE Order 231.1, by the Environmental Protection Department (EPD) at the Lawrence Livermore National Laboratory (LLNL). The results of LLNL's environmental monitoring and compliance effort and an assessment of the impact of LLNL operations on the environment and the public are presented in this publication.
Date: September 1, 1998
Creator: Biermann, A.H.; Althouse, P.E; Brandstetter, E.R.; Christofferson, E.C.; Fields, B.C.; Gallegos, G.M. et al.
Partner: UNT Libraries Government Documents Department

LLNL NESHAPs 1998 annual report

Description: This annual report is prepared pursuant to the National Emissions Standards for Hazardous Air Pollutants (NESHAPs) 40 CFR Part 61, Subpart H; Subpart H governs radionuclide emissions to air from Department of Energy (DOE) facilities. NESHAPs limits the emission of radionuclides to the ambient air from DOE facilities to levels resulting in an annual effective dose equivalent (EDE) of 10 mrem (100 {micro}Sv) to any member of the public. The EDEs for the Lawrence Livermore National Laboratory (LLNL) site-wide maximally exposed members of the public from 1998 operations are summarized here. (1) Livermore site: 0.055 mrem (0.55 {micro}Sv) (57% from point-source emissions, 43% from diffuse-source emissions). The point-source emissions include gaseous tritium modeled as tritiated water vapor as directed by EPA Region IX and is used for compliance purposes. LLNL believes a more realistic dose for the Livermore site is 0.049 mrem (0.49 {micro}Sv) (52% from point-source emissions, 48% from diffuse-source emissions). This dose is based on an assessment that represents a more realistic behavior of tritium gas in the environment. (2) Site 300: 0.024 mrem (0.24 {micro}Sv) (78% from point-source emissions, 22% from diffuse-source emissions). The EDEs were generally calculated using the EPA-approved CAP88-PC air-dispersion/dose-assessment model. Site-specific meteorological data, stack flow data, and emissions estimates based on radionuclide inventory data or continuous-monitoring systems data were the specific input to CAP88-PC for each modeled source.
Date: June 14, 1999
Creator: Berger, R. L.; Bertoldo, N. A.; Biermann, A. H.; Gallegos, G.; Hall, L. C.; Harrach, R. J. et al.
Partner: UNT Libraries Government Documents Department

Environmental Report 1998

Description: This summary provides an overview of LLNL's environmental activities in 1998, including radiological and nonradiological surveillance, effluent, and compliance monitoring, remediation, assessment of radiological releases and doses, and determination of the impact of LLNL operations on the environment and public health.
Date: September 22, 1999
Creator: Larson, J M; Harrach, R J; Althouse, P E; Bertoldo, N A; Biermann, A H; Blake, R G et al.
Partner: UNT Libraries Government Documents Department