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Estimated effective dose rates from radon exposure in workplaces and residences within Los Alamos county in New Mexico

Description: Many millions of office workers are exposed to radon while at work and at home. Though there has been a multitude of studies reporting the measurements of radon concentrations and potential lung and effective doses associated with radon and progeny exposure in homes, similar studies on the concentrations and subsequent effective dose rates in the workplace are lacking. The purposes of this study were to measure radon concentrations in office and residential spaces in the same county and explore the radiation dose implications. Sixty-five track-etch detectors were deployed in office spaces and 47 were deployed in residences, all within Los Alamos County, New Mexico, USA. The sampling periods for these measurements were generally about three months. The measured concentrations were then used to calculate and compare effective dose rates resulting from exposure while at work and at home. Results showed that full-time office workers receive on average about nine times greater exposure at home than while in the office (691 mrem yr{sup -1} versus 78 mrem yr{sup -1}). The estimated effective dose rate for a more homebound person was 896 mrem yr{sup -1}. These effective dose rates are contrasted against the 100 mrem yr{sup -1} threshold for regulation of a 'radiological worker' defined in the Department of Energy regulations occupational exposure and the 10 mrem yr{sup -1} air pathway effective public dose limit regulated by the Environmental Protection Agency.
Date: January 1, 2009
Creator: Whicker, Jeffrey J & Mcnaughton, Michael
Partner: UNT Libraries Government Documents Department

Dosimetric Significance of the ICRP's Updated Guidance and Models, 1989-2003, and Implications for U.S. Federal Guidance

Description: Over the past two decades the U.S. Environmental Protection Agency (EPA) has issued a series of Federal guidance documents for the purpose of providing the Federal and State agencies with technical information to assist their implementation of radiation protection programs. Currently recommended dose conversion factors, annual limits on intake, and derived air concentrations for intake of radionuclides are tabulated in Federal Guidance Report No. 11 (FGR 11), published in 1988. The tabulations in FGR 11 were based on dosimetric quantities and biokinetic and dosimetric models of the International Commission on Radiological Protection (ICRP) developed for application to occupational exposures. Since the publication of FGR 11 the ICRP has revised some of its dosimetric quantities and its models for workers and has also developed age-specific models and dose conversion factors for intake of radionuclides by members of the public. This report examines the extent of the changes in the inhalation and ingestion dose coefficients of FGR 11 implied by the updated recommendations of the ICRP, both for workers and members of the public.
Date: September 10, 2003
Creator: Leggett, R.W.
Partner: UNT Libraries Government Documents Department

Work to save dose: contrasting effective dose rates from radon exposure in workplaces and residences against the backdrop of public and occupational limits

Description: Office workers are exposed to radon while at work and at home. Though there has been a multitude of studies reporting the measurements of radon concentrations and potential lung and effective doses associated with radon and progeny exposure in homes, similar studies on the concentrations and subsequent effective dose rates in the non-mine workplaces are lacking. Additionally, there are few, if any, comparative analyses of radon exposures at more 'typical' workplace with residential exposures within the same county. The purposes of this study were to measure radon concentrations in office and residential spaces in the same county and explore the radiation dose implications. Sixty-five track-etch detectors were deployed in office spaces and 47 were deployed in residences, all within Los Alamos County, New Mexico, USA. The sampling periods for these measurements were generally about three months. The measured concentrations were used to calculate and compare effective dose rates resulting from exposure while at work and at home. Results showed that full-time office workers receive on average about 8 times greater exposure at home than while in the office (2.3 mSv yr-! versus 0.3 mSv yr-!). The estimated effective dose rate for a more homebound person was about 3 mSv yr-!. Estimating effective doses from background radon exposure in the same county as Los Alamos National Laboratory, with thousands of'radiological workers,' highlights interesting contrasts in radiation protection standards that span public and occupational settings. For example, the effective dose rate from background radon exposure in unregulated office spaces ranged up to 1.1 mSv yr-!, which is similar to the 1 mSv yr-! threshold for regulation ofa 'radiological worker,' as defined in the Department of Energy regulations for occupational exposure. Additionally, the estimated average effective dose total of> 3 mSv yf! from radon background exposure in homes stands in contrast to the ...
Date: January 1, 2009
Creator: Whicker, Jeffrey J & Mcnaughton, Michael W
Partner: UNT Libraries Government Documents Department

Changes in the peripheral blood transcriptome associated with occupational benzene exposure identified by cross-comparison on two microarray platforms

Description: Benzene is an established cause of leukemia and a possible cause of lymphoma in humans but the molecular pathways underlying this remain largely undetermined. This study sought to determine if the use of two different microarray platforms could identify robust global gene expression and pathway changes associated with occupational benzene exposure in the peripheral blood mononuclear cell (PBMC) gene expression of a population of shoe-factory workers with well-characterized occupational exposures to benzene. Microarray data was analyzed by a robust t-test using a Quantile Transformation (QT) approach. Differential expression of 2692 genes using the Affymetrix platform and 1828 genes using the Illumina platform was found. While the overall concordance in genes identified as significantly associated with benzene exposure between the two platforms was 26% (475 genes), the most significant genes identified by either array were more likely to be ranked as significant by the other platform (Illumina = 64%, Affymetrix = 58%). Expression ratios were similar among the concordant genes (mean difference in expression ratio = 0.04, standard deviation = 0.17). Four genes (CXCL16, ZNF331, JUN and PF4), which we previously identified by microarray and confirmed by real-time PCR, were identified by both platforms in the current study and were among the top 100 genes. Gene Ontology analysis showed over representation of genes involved in apoptosis among the concordant genes while Ingenuity{reg_sign} Pathway Analysis (IPA) identified pathways related to lipid metabolism. Using a two-platform approach allows for robust changes in the PBMC transcriptome of benzene-exposed individuals to be identified.
Date: March 1, 2009
Creator: McHale, Cliona M.; Zhang, Luoping; Lan, Qing; Li, Guilan; Hubbard, Alan E.; Forrest, Matthew S. et al.
Partner: UNT Libraries Government Documents Department

Cesium-137 in K west basin canister water

Description: Liquid and gas samples were taken from 50 K West Basin fuel storage canisters in 1996. The cesium-137 data from the liquid samples and an analysis of the data are presented. The analysis indicated that the cesium-137 data follow a lognormal distribution. Assuming that the total distribution of the K West canister water was predicted, the total K West Basin canister water was estimated to contain about 8,150 curies. The mean canister contains about 2.14 curies with as many as 5% or 190 of the canisters exceeding 19 curies. Opening ten canisters per shift could include a hot canister (cesium-137 > 25 curies) in one out of eight shifts.
Date: January 24, 1997
Creator: Trimble, D.J.
Partner: UNT Libraries Government Documents Department

Centrifuge workers study. Phase II, completion report

Description: Phase II of the Centrifuge Workers Study was a follow-up to the Phase I efforts. The Phase I results had indicated a higher risk than expected among centrifuge workers for developing bladder cancer when compared with the risk in the general population for developing this same type of cancer. However, no specific agent could be identified as the causative agent for these bladder cancers. As the Phase II Report states, Phase I had been limited to workers who had the greatest potential for exposure to substances used in the centrifuge process. Phase II was designed to expand the survey to evaluate the health of all employees who had ever worked in Centrifuge Program Departments 1330-1339 but who had not been interviewed in Phase I. Employees in analytical laboratories and maintenance departments who provided support services for the Centrifuge Program were also included in Phase II. In December 1989, the Oak Ridge Associated Universities (ORAU), now known as Oak Ridge Institute for Science and Education (ORISE), was contracted to conduct a follow-up study (Phase II). Phase H of the Centrifuge Workers Study expanded the survey to include all former centrifuge workers who were not included in Phase I. ORISE was chosen because they had performed the Phase I tasks and summarized the corresponding survey data therefrom.
Date: September 1, 1994
Creator: Wooten, H.D.
Partner: UNT Libraries Government Documents Department

Evaluation of HEPA filter service life

Description: Rocky Flats Environmental Technology Site (RFETS), has approximately 10,000 High Efficiency Particulate Air (HEPA) Filters installed in a variety of filter plenums. These ventilation/filtration plenum systems are used to control the release of airborne particulate contaminates to the environment during normal operations and potential accidents. This report summarizes the results of destructive and non-destructive tests on HEPA filters obtained from a wide variety of ages and service conditions. These tests were performed to determine an acceptable service life criteria for HEPA filters used at Rocky Flats Environmental Technology Site (RFETS). A total of 140 filters of various ages (1972 to 1996) and service history (new, aged unused, used) were tested. For the purpose of this report, filter age from manufacture date/initial test date to the current sample date was used, as opposed to the actual time a filter was installed in an operating system.
Date: July 14, 1997
Creator: Fretthold, J.K. & Stithem, A.R.
Partner: UNT Libraries Government Documents Department

Annual report for Hanford Site: Epidemiologic surveillance - 1994

Description: Epidemiologic surveillance at U.S. Department of Energy (DOE) facilities consists of regular and systematic collection, analysis, and interpretation of data on absences due to illness and injury in the work force. Its purpose is to provide an early warning system for health problems occurring among employees at participating sites. Data are collected by coordinators at each site and submitted to the Epidemiologic Surveillance Data Center, located at the Oak Ridge Institute for Science and Education, where quality control procedures and analyses are carried out. Rates of absences and rates of diagnoses associated with absences are analyzed by occupational and other relevant variables. They may be compared with the disease experience of different groups within the DOE work force and with populations that do not work for DOE to identify disease patterns or clusters that may be associated with work activities.This report provides the final summary for the Hanford Reservation.
Date: January 1, 1998
Partner: UNT Libraries Government Documents Department

Annual report for Brookhaven National Laboratory 1994 epidemiologic surveillance

Description: Epidemiologic surveillance at DOE facilities consists of regular and systematic collection, analysis, and interpretation of data on absences due to illness and injury in the work force. Its purpose is to provide an early warning system for health problems occurring among employees at participating sites. Data are collected by coordinators at each site and submitted to the Epidemiologic Surveillance Data Center, located at the Oak Ridge Institute for Science and Education, where quality control procedures and analyses are carried out. Rates of absences and rates of diagnoses associated with absences are analyzed by occupation and other relevant variables. They may be compared with the disease experience of different groups within the DOE work force and with populations that do not work for DOE to identify disease patterns or clusters that may be associated with work activities. In this annual report, the 1994 morbidity data for BNL are summarized. These analyses focus on absences of 5 or more consecutive workdays occurring among workers aged 16-80 years. They are arranged in five sets of tables that present: (1) the distribution of the labor force by occupational category and salary status; (2) the absences per person, diagnoses per absence, and diagnosis rates for the whole work force; (3) diagnosis rates by type of disease or injury; (4) diagnosis rates by occupational category; and (5) relative risks for specific types of disease or injury by occupational category.
Date: January 1, 1997
Partner: UNT Libraries Government Documents Department

Silica exposure to excavation workers during the excavation of a low level radiological waste pit and tritium disposal shafts

Description: This study evaluated the task-length average (TLA) respirable dust and respirable silica airborne concentrations to which construction workers excavating volcanic tuff at Los Alamos National Laboratory (LANL) were exposed. These workers were excavating a low level radiological waste disposal pit of final dimensions 720 feet long, 132 feet wide and 60 feet deep. The objectives of this study were as follows: (1) evaluate exposures; (2) determine if the type of machinery used affects the respirable dust concentration in the breathing zone of the worker; (3) evaluate the efficacy of wetting the pit to reduce the respirable dust exposure; and (4) determine if exposure increases with increasing depth of pit due to the walls of the pit blocking the cross wind ventilation.
Date: January 1, 1995
Creator: Wilson, K.M.
Partner: UNT Libraries Government Documents Department

Historical summary and recommendations on Melanoma in the LLNL workforce

Description: This document provides a historical summary and recommendations on melanoma in the Lawrence Livermore National Laboratory (LLNL) workforce. Melanoma of the skin comprises about 3.5% of the incidence (38,000 new cases in 1991) and 1.7% of the mortality (8500 deaths in 1991) of all cancer in the U.S. However, for several decades it has shown the fastest rate of increase of any cancer site. The following areas are discussed: background and recognition of increased melanoma at LLNL, history of melanoma studies at LLNL, results from occupational factors study, overall conclusion on increased melanoma incidence, and recommendations for future management.
Date: December 1, 1994
Creator: Moore, D.H. II & Hatch, F.
Partner: UNT Libraries Government Documents Department

Practical and cost effective solution to the need for shielding penetrations against photons and neutrons from normal and accident losses

Description: The Thomas Jefferson National Accelerator Facility (Jefferson Lab) houses a 4 GeV, 200 {micro}A continuous wave (CW) recirculating electron accelerator. This underground accelerator is made up of two superconducting linear accelerators (linacs), two arcs, a beam switch yard (BSY), and three end stations. Each linac has the capability of accelerating electrons to a kinetic energy of 400 MeV. The arcs contain four (on the west) and five (on the east) beamlines to transport the beams of differing energies back into the linacs. The BSY steers the desired beams into the end stations as needed for nuclear physics experiments. The accelerator is connected to the control and diagnostic electronics in the above-ground service buildings via 30 cm and 51 cm diameter penetrations that travel through 4.6 m of soil and concrete. As a result, there exists the potential for personnel exposure to radiation scattering up the penetrations. It was desired that some of these buildings become Uncontrolled Areas, so that persons in the buildings would not require dosimetry. The Jefferson Lab Beam Containment Policy also requires that effective dose rates to workers be limited to 150 mSv in one hour if a maximum beam power loss accident was to continue unabated.
Date: January 1, 1997
Creator: Schwahn, S.
Partner: UNT Libraries Government Documents Department

Implementation guide for use with DOE Order 440.1: Occupational exposure assessment

Description: DOE O 440.1, Worker Protection Management for DOE Federal and Contractor Employees, establishes the framework for an effective worker protection program that will reduce or prevent accidental injuries and illnesses. One element of the worker protection program in DOE O 440.1 is Exposure Assessment (EA). This Guide provides acceptable methodologies for conducting EA for workers. Exposure assessment should be included in the DOE and contractor written worker protection program, as required by DOE O 440.1. EA documentation should describe the methods and rationale a site uses to characterize and monitor workers` potential and actual exposures to hazardous agents. DOE O 440.1 applies to all activities (including design, construction, operation, maintenance, decontamination and decommissioning, research and development, and environmental restoration activities) performed by DOE and its contractors (and their subcontractors).
Date: March 30, 1998
Partner: UNT Libraries Government Documents Department

Amended annual report for Brookhaven National Laboratory: Epidemiologic surveillance - 1994

Description: Epidemiologic surveillance at DOE facilities consists of regular and systematic collection, analysis, and interpretation of data on absences due to illness and injury in the work force. Its purpose is to provide an early warning system for health problems occurring among employees at participating sites. Data are collected by coordinators at each site and submitted to the Epidemiologic Surveillance Data Center, located at the Oak Ridge Institute for Science and Education, where quality control procedures and analyses are carried out. Rates of absences and rates of diagnoses associated with absences are analyzed by occupation and other relevant variables. They may be compared with the disease experience of different groups within the DOE work force and with populations and do not work for DOE to identify disease patterns or clusters that may be associated work activities. This report provides a final summary for BNL.
Date: December 31, 1998
Partner: UNT Libraries Government Documents Department

Summary of contamination control practices at Thomas Jefferson National Accelerator Facility

Description: It is often the belief that electron accelerators are clean machines, producing little or no measurable removable contamination. However, at the Thomas Jefferson National Accelerator Facility (Jefferson Lab), a 200 {micro}A continuous wave, 4 GeV electron accelerator, there are several types of contamination that may be found: external contamination of beamline components near high beam loss points, radionuclides produced from the spallation of oxygen in air, and internal contamination of water systems used to cool beamline components. The last two categories, however, are fairly well understood and are not discussed herein. The Jefferson Lab Radiation Control Group has developed a comprehensive set of contamination control practices to identify and control personnel exposure to these radionuclides.
Date: January 1, 1997
Creator: May, R.; Schwahn, S. & Welch, K.
Partner: UNT Libraries Government Documents Department

Radiological control manual. Revision 1

Description: This Lawrence Berkeley National Laboratory Radiological Control Manual (LBNL RCM) has been prepared to provide guidance for site-specific additions, supplements and interpretation of the DOE Radiological Control Manual. The guidance provided in this manual is one methodology to implement the requirements given in Title 10 Code of Federal Regulations Part 835 (10 CFR 835) and the DOE Radiological Control Manual. Information given in this manual is also intended to provide demonstration of compliance to specific requirements in 10 CFR 835. The LBNL RCM (Publication 3113) and LBNL Health and Safety Manual Publication-3000 form the technical basis for the LBNL RPP and will be revised as necessary to ensure that current requirements from Rules and Orders are represented. The LBNL RCM will form the standard for excellence in the implementation of the LBNL RPP.
Date: May 1, 1996
Creator: Kloepping, R.
Partner: UNT Libraries Government Documents Department

Internal dosimetry of tritium

Description: Tritium is an interesting radionuclide from the perspective of internal dosimetry because of the wide variety of chemical compounds in which it can appear, its unusual routes of entry into the body, and its ability to exchange with stable hydrogen in surrounding material. In this report the internal dosimetry of tritium compounds is reviewed, with emphasis on methods of evaluating bioassay data following chronic and acute intakes. The assumptions and models used in the derivation of Annual Limits on Intake (ALI) and Derived Air Concentrations (DAC) for tritium are also discussed.
Date: June 1, 1992
Creator: LaBone, T. R.
Partner: UNT Libraries Government Documents Department

Irradiation Processing Department Investigation Report: Localized Exposure Exceeding Operational Control

Description: This investigation report discusses the exposure of a maintenance craftsman to a radioactive particle found on his face which could have contributed to a dose as high as 4.6 rads. The craftsman had been working at the discharge area. (JL)
Date: April 12, 1961
Creator: Jerman, P. C.
Partner: UNT Libraries Government Documents Department

Formaldehyde as a basis for residential ventilation rates

Description: Traditionally, houses in the U.S. have been ventilated by passive infiltration in combination with active window opening. However in recent years, the construction quality of residential building envelopes has been improved to reduce infiltration, and the use of windows for ventilation also may have decreased due to a number of factors. Thus, there has been increased interest in engineered ventilation systems for residences. The amount of ventilation provided by an engineered system should be set to protect occupants from unhealthy or objectionable exposures to indoor pollutants, while minimizing energy costs for conditioning incoming air. Determining the correct ventilation rate is a complex task, as there are numerous pollutants of potential concern, each having poorly characterized emission rates, and poorly defined acceptable levels of exposure. One ubiquitous pollutant in residences is formaldehyde. The sources of formaldehyde in new houses are reasonably understood, and there is a large body of literature on human health effects. This report examines the use of formaldehyde as a means of determining ventilation rates and uses existing data on emission rates of formaldehyde in new houses to derive recommended levels. Based on current, widely accepted concentration guidelines for formaldehyde, the minimum and guideline ventilation rates for most new houses are 0.28 and 0.5 air changes per hour, respectively.
Date: April 28, 2002
Creator: Sherman, M.H. & Hodgson, A.T.
Partner: UNT Libraries Government Documents Department

ANALYSIS OF VAPORS FROM METHYLENE CHLORIDE EXTRACTS OF NUCLEAR GRADE HEPA FILTER FIBERGLASS SAMPLES

Description: While several organic compounds were detected in the vapor samples used in the reenactment of the preparation of mounts from the extracts of nuclear grade high-efficiency particulate air filter fiberglass samples, the most significant species present in the samples were methylene chloride, phenol, phenol-d6, and 2-fluorophenol. These species were all known to be present in the extracts, but were expected to have evaporated during the preparation of the mounts, as the mounts appeared to be dry before any vapor was collected. These species were present at the following percentages of their respective occupational exposure limits: methylene chloride, 2%; phenol, 0.4%; and phenol-d6, 0.6%. However, there is no established limit for 2-fluorophenol. Several other compounds were detected at low levels for which, as in the case of 2-fluorophenol, there are no established permissible exposure limits. These compounds include 2-chlorophenol; N-nitroso-1-propanamine; 2-fluoro-1,1{prime}-biphenyl; 1,2-dihydroacenaphthylene; 2,5-cyclohexadiene-1,4-dione,2,6-bis(1,1-dimethylethyl); trimethyl oxirane; n-propylpropanamine; 2-(Propylamino)ethanol; 4-methoxy-1-butene; 6-methyl-5-hepten-2-one; and 3,4-dimethylpyridine. Some of these were among those added as surrogates or spike standards as part ofthe Advanced Technologies and Laboratories International, Inc. preparation ofthe extract of the HEPA filter media and are indicated as such in the data tables in Section 2, Results; other compounds found were not previously known to be present. The main inorganic species detected (sulfate, sodium, and sulfur) are also consistent with species added in the preparation of the methylene chloride extract of the high-efficiency particulate air sample.
Date: June 7, 2012
Creator: JM, FRYE; HL, ANASTOS & FC, GUTIERREZ
Partner: UNT Libraries Government Documents Department

Sampling and Analysis Issues Relating to the ACGIH Notice of Intended Change for the Beryllium Threshold Limit Value

Description: Beryllium in various forms is widely used throughout the world in ceramics, aerospace and military applications, electronics, and sports equipment. Workplace exposure to beryllium is a growing industrial hygiene concern due to the potential for development of chronic beryllium disease (CBD), a lung condition with no known cure, in a small percentage of those exposed. There are workplace exposure limits for beryllium that have been in place for several decades. However, recent studies suggest that the current American Conference of Governmental Industrial Hygienists (ACGIH) Threshold Limit Value (TLV) and the Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (PEL) may not be sufficiently protective for workers who are potentially exposed to airborne beryllium. Early in 2005, ACGIH issued a Notice of Intended Change (NIC) to the current TLV for beryllium which entails a 100-fold reduction (from 2 to 0.02 micrograms per cubic meter of sampled air). It is noted that ACGIH TLVs do not carry legal force in the manner that OSHA PELs or other federal regulations do. Nevertheless, OSHA plans a beryllium rulemaking in the near future, and a reduction in the PEL is anticipated. Also, if this change in the TLV for beryllium is adopted, it is reasonable to assume that at least some sampling and analysis activities will need to be modified to address airborne beryllium at the lower levels. There are implications to both the industrial hygiene and the laboratory communities, which are discussed.
Date: August 16, 2005
Creator: Brisson, Michael J. & Ashley, Kevin
Partner: UNT Libraries Government Documents Department

Statistical Methods and Software for the Analysis of Occupational Exposure Data with Non-detectable Values

Description: Environmental exposure measurements are, in general, positive and may be subject to left censoring; i.e,. the measured value is less than a ''detection limit''. In occupational monitoring, strategies for assessing workplace exposures typically focus on the mean exposure level or the probability that any measurement exceeds a limit. Parametric methods used to determine acceptable levels of exposure, are often based on a two parameter lognormal distribution. The mean exposure level, an upper percentile, and the exceedance fraction are used to characterize exposure levels, and confidence limits are used to describe the uncertainty in these estimates. Statistical methods for random samples (without non-detects) from the lognormal distribution are well known for each of these situations. In this report, methods for estimating these quantities based on the maximum likelihood method for randomly left censored lognormal data are described and graphical methods are used to evaluate the lognormal assumption. If the lognormal model is in doubt and an alternative distribution for the exposure profile of a similar exposure group is not available, then nonparametric methods for left censored data are used. The mean exposure level, along with the upper confidence limit, is obtained using the product limit estimate, and the upper confidence limit on an upper percentile (i.e., the upper tolerance limit) is obtained using a nonparametric approach. All of these methods are well known but computational complexity has limited their use in routine data analysis with left censored data. The recent development of the R environment for statistical data analysis and graphics has greatly enhanced the availability of high-quality nonproprietary (open source) software that serves as the basis for implementing the methods in this paper.
Date: September 20, 2005
Creator: Frome, EL
Partner: UNT Libraries Government Documents Department

Occupational Exposure to Benzene from Painting with Epoxy and Other High Performance Coatings

Description: Following the discovery of trace benzene in paint products, an assessment was needed to determine potential for benzene exposures to exceed the established ACGIH Threshold Limit Value (TLV) during painting operations. Sample data was collected by area industrial hygienists for benzene during routine maintenance and construction activities at Savannah River Site. A set of available data from the IH database, Sentry, was analyzed to provide guidance to the industrial hygiene staff and draw conclusions on the exposure potential during typical painting operations.
Date: April 20, 2005
Creator: JAHN, STEVEN
Partner: UNT Libraries Government Documents Department