beryllium concentration initial
Human urinary and blood toxicokinetics of beryllium
High initial systemic beryllium exposure after multi-faceted accidental exposure. •. Conform elimination kinetics of beryllium in both blood and urine. •. First …
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CHAPTER 3. TOXICOKINETICS, SUSCEPTIBLE …
undetermined concentration for 10–20 hours. The day after exposure, mean serum beryllium levels were 3.5±0.47 ppb beryllium, compared to 1.0 ppb in unexposed controls. Six days later, the mean serum level of the exposed group had decreased to 2.4±0.3 ppb beryllium (Zorn et al. 1986). After accidental
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Beryllium
This is calculated by combining the scores for crustal abundance, reserve distribution, production concentration, substitutability, recycling rate and political stability scores. Crustal abundance (ppm) The number of atoms of the element per 1 million atoms of the …
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AMERICAN THORACIC SOCIETY DOCUMENTS
presenting cells in the presence of beryllium activates beryllium-speci ficCD41 Tcells, inducing an oligoclonal expansion specific for both beryllium and compartmentalization to the lung (53–55) (Figure 1). Noncaseating granulomas develop (56–59), which usually include multinucleated giant cells. The morphology of the granuloma may vary from
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Metal Allergy: Beryllium | SpringerLink
The two workers were exposed to lower beryllium concentrations than workers in the 1940s, and both left employment with a diagnosis of CBD years after initial exposure. Differences in solubility of beryllium compounds were thought to explain differences in disease presentation and progression.
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Interim Enforcement Guidance for the 2020 Final Beryllium …
Requires both initial and periodic monitoring: Employers must perform initial monitoring as soon as work begins to determine exposure levels and where to implement control measures. ... Solutions containing beryllium in concentrations greater than or equal to 0.1 % by weight; or (3) Visible dust, fumes, or mists containing beryllium in ...
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Mathematical model: Retention of beryllium on flow-through fixed …
Aliquot samples were taken from the column at appropriate time intervals as necessary. Batch sorption studies of beryllium and the concentrations of beryllium were analyzed as previously reported [13]. All experiments were performed at pH of 3.5 in duplicate and the averaged values were taken. 3. Physical picture and assumptions
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On use of beryllium in fusion reactors: Resources, impurities and
A specific activity of the beryllium with initial U concentration of 30 wppm after 300 years of cooling ranges from 3 kBq/g (for ITER) to 90 kBq/g (for demonstration and power reactors) [12], [15]. Under Russian regulations rules [16], the beryllium containing transuranic radionuclides with their total specific activity higher than 10 Bq/g is ...
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Beryllium Metal II. A Review of the Available Toxicity Data
The only studies that partly match this study type are studies with an initial acute or subacute inhalation exposure period (often targeting at in initial lung burden) and an extended follow-up period ... so despite of the only moderate achieved concentrations of beryllium ions in the extracts, the cells were exposed sufficiently, and exposure ...
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1926.1124
Action level means a concentration of airborne beryllium of 0.1 micrograms per cubic meter of air (μg/m 3) calculated as an 8-hour time-weighted average (TWA). ... Where the most recent (non-initial) exposure monitoring indicates that airborne exposure is below the action level, the employer must repeat such monitoring within six months of the ...
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Synthesis and characterization of modified sulfonated chitosan for
The capacity of the sorbent was determined by using the mass balance equation (Q eq = ((C o − C eq) V/m), while C o, C eq are the initial and equilibrium concentration of beryllium ions in the solution (ppm), (V) is the volume of the solution (L) and (m) is the weight of the sorbent (g). Uptake kinetics was achieved by mixing 20 mg …
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Division 2, Subdivision Z, Beryllium
employee is exposed to an airborne concentration of beryllium in excess of 0.2 µg/m3 calculated as an 8-hour TWA. (2) Short-term exposure limit (STEL). The employer must ensure that no employee is exposed to an airborne concentration of beryllium in excess of 2.0 µg/m3 as determined over a sampling period of 15 minutes.
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BERYLLIUM AND BERYLLIUM COMPOUNDS (CICAD 32, 2001)
A survey of beryllium concentrations in Japanese cities reported an average value of 0.042 ng/m 3 and a maximum value of 0.222 ng/m 3 (Ikebe et al., 1986). Urban areas in Germany had beryllium concentrations ranging from 0.06 to 0.33 ng/m 3 (Mueller, 1979; Freise & Israel, 1987).
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Beryllium Reduction Potential in AlMg Cast Alloys
The oxidation rate of AlMg alloys with 3–20 wt% magnesium and 5–200 ppm beryllium was investigated extensively by Thiele [].The experiments by Thiele were performed with a similar sample size of 27 ± 0.1 g compared to this work and an initial surface area of 8.5 cm 2.Each sample was heated in a vertical tube induction furnace, in …
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Buffalo District > Missions > HTRW > FUSRAP > Luckey Site
The initial tap water sample collected at the first residence north of the site in July 1998 contained beryllium at a concentration of 7.7 parts per billion (ppb), which exceeded the U.S. Environmental Protection Agency Maximum Concentration Level (MCL) of 4 ppb.
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Beryllium Data Sheet
Beryllium ores and concentrates Beryllium oxide and hydroxide Beryllium-copper master alloy Beryllium-copper plates, sheets, and strip: Thickness of 5 millimeters (mm) …
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eCFR :: 29 CFR 1910.1024 -- Beryllium.
This standard means this beryllium standard, 29 CFR 1910.1024. ( c) Permissible Exposure Limits (PELs) —. ( 1) Time-weighted average (TWA) PEL. The employer must ensure that no employee is exposed to an airborne concentration of beryllium in excess of 0.2 µg/m 3 calculated as an 8-hour TWA. ( 2) Short-term exposure limit (STEL).
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Beryllium
Element Beryllium (Be), Group 2, Atomic Number 4, s-block, Mass 9.012. Sources, facts, uses, scarcity (SRI), podcasts, alchemical symbols, videos and images. ... Production concentration. The percentage of an element produced in the top producing country. The higher the value, the larger risk there is to supply. ...
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Beryllium
The beryllium standard for general industry defines dermal contact with beryllium as skin exposure to: (1) soluble beryllium compounds containing beryllium in concentrations greater than or equal to 0.1 percent by weight; (2) solutions containing beryllium in concentrations greater than or equal to 0.1 percent by weight; or (3) visible dust ...
ادامه مطلب1910.1024 clean text
employer must ensure that no employee is exposed to an airborne concentration of beryllium in excess of 0.2 μg/m3 calculated as an 8-hour TWA. (2) Short-term exposure limit (STEL). The employer must ensure that no employee is exposed to an airborne concentration of beryllium in excess of 2.0 μg/m3 as determined over a sampling …
ادامه مطلبBERYLLIUM in Air by Fluorometry 7704
These standards with lower beryllium concentration can be prepared by 10-fold dilution of the stock standards mentioned in the note above. As with the samples, these stock standards are prepared for analysis by adding 0.4 mL of beryllium stock standard into 1.6 mL of detection solution (5-fold dilution). Please see Table 2.
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Beryllium Compounds
The average concentration of beryllium measured in the air in the United States during the 1980s was 0.03 nanograms per cubic meter (ng/m 3). Ambient concentrations measured …
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Beryllium | Be (Element)
Today, beryllium is primarily obtained from the minerals beryl (Be 3 Al 2 (SiO 3) 6) and bertrandite (4BeO·2SiO 2 ·H 2 O) through a chemical process or through the electrolysis …
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Beryllium Compounds
The average concentration of beryllium measured in the air in the United States during the 1980s was 0.03 nanograms per cubic meter (ng/m 3). Ambient concentrations measured in 50 cities between 1977 and 1981 were 0.1-0.4 ng/m 3. (1) Assessing Personal Exposure
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The chemical nature of sodium beryllate solutions
The stability of beryllate solutions on heating. Beryllium is normally recovered from a beryllate solution by heating it at, or near, its boiling point to precipitate granular beryllium hydroxide. The effects of changing the ratio of Na20/BeO and the initial beryllium concentration on the recovery of beryllium on heating are shown in Figs. 2 and 3.
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California Code of Regulations, Title 8, Section 5205. Beryllium.
The employer must ensure that no employee is exposed to an airborne concentration of beryllium in excess of 0.2 μg/m 3 calculated as an 8-hour TWA. (2) Short-term exposure limit (STEL). ... Where the most recent (non-initial) exposure monitoring indicates that airborne exposure is below the action level, the employer must repeat such ...
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BERYLLIUM & COMPOUNDS (as Be) | Occupational Safety and …
ANSI: American National Standard Acceptable Concentrations of Beryllium and Beryllium Compounds. May 26, 1970. California Occupational Safety & Health Standards Board Initial and Final Statement of Reasons July 6, 2006. EPA Beryllium and compounds (CASRN ) 1998.
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GUIDE FOR COMPLIANCE OSHA BERYLLIUM …
beryllium in concentrations greater than or equal to 0.1 percent by weight; (2) Solutions containing beryllium in concentrations greater than or equal to 0.1 percent by weight; or (3) Visible dust, fumes, ... The employer must perform initial monitoring to assess the 8-hour TWA exposure for
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Neogene continental denudation and the beryllium …
The constant partition coefficient of beryllium means that the ratio of the concentration of absorbed Be in the suspended particles to the dissolved Be concentration in water is constant. Therefore, the …
ادامه مطلبRadioisotopes demonstrate changes in global atmospheric
Most long-term data sets of beryllium-7 concentration, like a, c, d, e, and f (Canada, Hawaii, Japan, Mongolia, Tristan da Cunha respectively), exhibited over the last two decades a broadening of ...
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