Standard Methods: 4500-F-D: Fluoride in Water by Spectroscopy
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Official Method Name
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Test Method D. SPADNS Method |
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Current Revision
| Standard Methods Online |
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Media
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WATER |
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Instrumentation
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Spectroscopy (Colorimetry; Photometry) |
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Method Subcategory
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Inorganic |
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Method Source
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Citation
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Brief Method Summary
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Based on the reaction between fluoride and a zirconium-dye lake. Fluoride dissociates a portion of the dye lake into a colorless complex anion and the dye. As the amount of fluoride increases, the color produced becomes progressively lighter. |
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Scope and Application
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This method covers the determination of fluoride in drinking water. |
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Applicable Concentration Range
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0 to 1.40 mg fluoride/L |
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Interferences
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Positive error from alkalinity. Negative error from aluminum, iron, and sulfate. All known interferences eliminated or reduced by distillation |
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Quality Control Requirements
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Analysis of standards for accuracy check. |
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Sample Handling
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Maximum Holding Time
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28 days |
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Relative Cost
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Less than $50 |
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Sample Preparation Methods
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Preliminary distillation step, 4500-F- B |
