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Elmore, OH, United States

Deubner D.C.,Materion Brush Inc. | Roth H.D.,Roth Associ.
Journal of Occupational and Environmental Medicine | Year: 2015

Purpose: This study explores how highly correlated time variables (occupational cohort time scales) contribute to confounding and ambiguity of interpretation. Methods: Occupational cohort time scales were identified and organized through simple equations of three time scales (relational triads) and the connections between these triads (time scale web). The behavior of the time scales was examined when constraints were imposed on variable ranges and interrelationships. Results: Constraints on a time scale in a triad create high correlations between the other two time scales. These correlations combine with the connections between relational triads to produce association paths. High correlation between time scales leads to ambiguity of interpretation. Conclusions: Understanding the properties of occupational cohort time scales, their relational triads, and the time scale web is helpful in understanding the origins of otherwise obscure confounding bias and ambiguity of interpretation. Copyright © 2015 by American College of Occupational and Environmental Medicine. Source


Thomas C.A.,U.S. National Institute for Occupational Safety and Health | Deubner D.C.,Materion Brush Inc. | Stanton M.L.,U.S. National Institute for Occupational Safety and Health | Kreiss K.,U.S. National Institute for Occupational Safety and Health | Schuler C.R.,U.S. National Institute for Occupational Safety and Health
American Journal of Industrial Medicine | Year: 2013

Background: In 2000, a manufacturer of beryllium materials and products introduced a comprehensive program to prevent beryllium sensitization and chronic beryllium disease (CBD). We assessed the program's efficacy in preventing sensitization 9 years after implementation. Methods: Current and former workers hired since program implementation completed questionnaires and provided blood samples for the beryllium lymphocyte proliferation test (BeLPT). Using these data, as well as company medical surveillance data, we estimated beryllium sensitization prevalence. Results: Cross-sectional prevalence of sensitization was 0.7% (2/298). Combining survey results with surveillance results, a total of seven were identified as sensitized (2.3%). Early Program workers were more likely to be sensitized than Late Program workers; one of the latter was newly identified. All sensitization was identified while participants were employed. One worker was diagnosed with CBD during employment. Conclusions: The combination of increased respiratory and dermal protection, enclosure and improved ventilation of high-risk processes, dust migration control, improved housekeeping, and worker and management education showed utility in reducing sensitization in the program's first 9 years. The low rate (0.6%, 1/175) among Late Program workers suggests that continuing refinements have provided additional protection against sensitization compared to the program's early years. © 2013 Wiley Periodicals, Inc. Source


Deubner D.C.,Materion Brush Inc.
Journal of Occupational and Environmental Medicine | Year: 2013

Objective: Common variation is a statistical process-control term for variability associated with usual operating conditions. Special variation occurs when usual operating conditions are disrupted. The objective was to explore the implications for preventive occupational medicine practice of common and special variation in air-level exposure. Methods: Illustrations are derived from US and UK beryllium facility databases. Results: Special variation may be missed in finite sampling sets, giving a very inaccurate indication of the highest air levels experienced on the job. Depending on the toxicologic model, failure to assess special variation influences the meaningfulness of aspects of occupational prevention, from medical surveillance through risk management. Conclusions: Jobs and tasks should be characterized for special variation in addition to traditional air sampling. Both special variation and common variation should be considered in occupational medicine preventive practice. Copyright © 2013 by American College of Occupational and Environmental Medicine. Source


Trademark
Materion Brush Inc. and Brush Wellman Inc | Date: 2012-07-31

Copper beryllium rod and plate.


Abbas Virji M.,U.S. National Institute for Occupational Safety and Health | Park J.Y.,U.S. National Institute for Occupational Safety and Health | Stefaniak A.B.,U.S. National Institute for Occupational Safety and Health | Stanton M.L.,U.S. National Institute for Occupational Safety and Health | And 4 more authors.
Scandinavian Journal of Work, Environment and Health | Year: 2012

Objectives Previous epidemiologic studies of beryllium sensitization (BeS) and chronic beryllium disease (CBD) have reported inconsistent exposure-response relationships, likely due to exposure misclassification. The objective of this study was to develop historical estimates of size-selective personal exposure to beryllium for an epidemiologic study. Methods In 1999, a cross-sectional survey of workers hired after 1 January 1994 was conducted at a beryllium production facility. Personal exposure data from two air sampling surveys conducted in 1999 were used to obtain total, respirable, and submicron particle baseline exposure estimates (BEE) for a job-exposure matrix (JEM). General area air samples collected from 1994-1999 were used to estimate annual changes in exposures (temporal factors) for 24 different process areas. Historical exposure estimates (HEE) were calculated by applying the temporal factors to the BEE. Workers were assigned HEE based on their work history, and their historical exposure profile was summarized as cumulative, average, or highest-ever job exposure. Results Changes in exposure over a 6-year period were observed in 10 of the 24 process areas with an overall mean decline of 18% per year. The overall total exposure for study participants over their work tenure ranged from: 0.001-34.44 μg/m3-year, 0.01-16.26 μg/m3, and 0.01-17.54 μg /m3 for cumulative, average, and highest-ever job, respectively. For respirable exposures, the ranges were: 0.001-15.54 μg/m3-year, 0.01-3.56 μg/m3, 0.01-5.54 μg /m3 for cumulative, average, and highest-ever job, respectively. Conclusions Using this JEM, exposure-response relationships for BeS and CBD can be explored over a range of exposure metrics such as total, respirable, and submicron beryllium mass concentrations, including summary measures such as cumulative, average, or highest exposures, with the ultimate objective of elucidating a quantitative exposure-response relationship. Source

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