Standard Methods: 3030B: Preliminary Filtration of Metals Samples
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Official Method Name
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Preliminary Filtration of Samples for Metals Analyses |
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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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Preparatory Procedure |
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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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Before filtering the sample, precondition the plastic filtering device by filtering a blank made up of reagent water. Precondition filter by rinsing with 50 mL deionized water. If significant amounts of metals are found in the preconditioned filtrate (blank), soak the filter in 0.5 N HCl or 1+1 HNO3 and rinse with water before use. Before filtering, centrifuge turbid samples. If determining dissolved or suspended metals, filter sample at time of collection. If digesting the filter for suspended metals, record sample volume filtered. After filtering, acidify filtrate to pH 2 with concentrated HNO3. If precipitate forms upon acidification, perform nitric acid digestion on filtrate before analysis (see abstract in Method 3030-E). |
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Scope and Application
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This method is applicable to the preliminary treatment of water samples using filtration. |
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Applicable Concentration Range
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Interferences
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Metals introduced during preliminary treatment from equipment common to environmental labs. |
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Quality Control Requirements
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Check reagent grade acids for purity. Process blanks through all digestion and filtration steps. |
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Sample Handling
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Collect sample in plastic or glass container which has been rinsed with 1+1 HNO3. Adjust the pH of the sample to < 2 with HNO3. For dissolved metals, filter samples immediately. Analyze within 6 months. |
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Maximum Holding Time
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6 months |
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Relative Cost
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Less than $50 |
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Sample Preparation Methods
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