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Showing 1 to 11 of 11 for “"Lead leaching"”.
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Dezincification and Brass Lead Leaching in Premise Plumbing Systems: Effects of Alloy, Physical Conditions and Water Chemistry
… by "dezincification," which is the selective leaching of zinc from the alloy. Dezincification in potable water systems has important practical consequences that include clogged water lines, premature system failure and leaks, and release of contaminants such as lead. Brass failures attributed …
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Chloride Sulfate Mass Ratio (CSMR) and Nitrate Acceleration of Galvanic Lead- Bearing Solder Corrosion
Lead corrosion in premise plumbing systems from materials, such as lead pipes, soldered joints, and brass, can cause elevated lead in drinking water. This work examined mechanisms by which galvanic corrosion of lead solder:copper joints is accelerated by high chloride, low sulfate, and high nitrate …
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Lead and Copper Corrosion Control in New Construction: Shock Chlorination, Flushing to Remove Debris & In-line Device Product Testing
… shock chlorination of new plumbing lines, and 3) lead leaching propensity of new brass ball valves. During installation of plumbing systems, residual chemicals and debris including copper brass particles and flux, can be left in plumbing lines following construction and installation. This debris …
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Addressing and Assessing Lead Threats in Drinking Water: Non-Leaded Brass, Product Testing, Particulate Lead Occurrence and Effects of the Chloride to Sulfate Mass Ratio on Corrosion
… over adverse health effects from low level lead exposure motivated reassessment of lead occurrence in drinking water, from the perspective of 1) possibly eliminating lead from new brass materials, and 2) performance testing of existing products. During the course of this thesis work, it was …
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Evaluation of Zinc Orthophosphate to Control Lead Solder Corrosion in Waters With High Chloride to Sulfate Mass Ratio
… mass ratio (CSMR) and trigger serious water lead contamination from galvanic lead solder: copper pipe corrosion. Previous attempts to control this problem through simple water chemistry modifications were unsuccessful, but in this work a combination of zinc orthophosphate and moderate …
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Galvanic Lead Corrosion in Potable Water: Mechanisms, Water Quality Impacts, and Practical Implications
As stagnant water contacts copper pipe and lead solder (simulated soldered joints), a corrosion cell is formed between the metals in solder (Pb, Sn) and copper. If the resulting galvanic current exceeds about 2 µA/cm², a highly corrosive microenvironment can form at the solder surface, with pH <2.5 …
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Insights Into Non-Uniform Copper and Brass Corrosion in Potable Water Systems
… increased temperature can significantly increase lead leaching from brass. Following recent outbreaks of brass dezincification failures, NSF/ANSI Standard 14 has been revised to require that all NSF 14-listed brass is dezincification resistant, as certified by satisfactory results from an …
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Practical Impacts of Galvanic Corrosion in Water Service Lines and Premise Plumbing
… concern about the potential for elevated lead in water after water utilities conduct EPA mandated (or voluntary) partial replacements of existing lead service lines. Connections between dissimilar metals results in the accelerated corrosion of the less noble metal via galvanic attack, …
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Characterizing Waterborne Lead in Private Water Systems
Lead is a common additive in plumbing components despite its known adverse health effects. Recent research has attributed cases of elevated blood lead levels in children and even fetal death with the consumption of drinking water containing high levels of lead. Although the federal Environmental …
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Study of Size Reduction, Reliability and Lead Safety of an Intra-Cochlear Lead-Zirconate-Titanate Micro-Actuator
… team has been developing a novel intra-cochlear lead-zirconate-titanate (PZT) micro-actuator to generate acoustic wave directly in the inner ear. Current design of the intra-cochlear micro-actuator is a square PZT diaphragm anchored at all four edges forming a tiny speaker. The purpose of this …
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Corrosion in New Construction:Elevated Copper, Effects of Orthophosphate Inhibitors, and Flux Initiated Microbial Growth
… work has also demonstrated that problems with lead leaching to water from brass in modern plumbing can actually be worse in PVC/plastic than in copper systems, if certain types of microbes such as nitrifiers proliferate and drop pH. Some of the problems initiated by construction practices can …