EPA-NERL: 160.1: Filterable Residue by Drying Oven
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Official Method Name
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Residue, Filterable (Gravimetric, Dried at 180 oC) |
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Current Revision
| Issued 1971 |
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Media
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WATER |
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Instrumentation
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Gravimetry |
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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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A well-mixed sample is filtered through a standard glass fiber filter. The filtrate is evaporated and dried to constant weight at 180oC. |
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Scope and Application
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This method determines filterable residue in drinking, surface, and saline waters; domestic and industrial wastes. |
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Applicable Concentration Range
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10 - 20,000 mg/L |
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Interferences
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(A) Mineral Waters: Highly mineralized waters containing significant concentrations of calcium, magnesium, chloride and/or sulfate may be hygroscopic and will require prolonged drying, desiccation and rapid weighing. (B) Bicarbonate: Samples containing high concentrations of bicarbonate will require careful and possibly prolonged drying at 180oC to insure that all the bicarbonate is converted to carbonate. (C) High Residue Levels: Too much residue in the evaporating dish will crust over and entrap water that will not be driven off during drying. Total residue should be limited to about 200 mg. |
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Quality Control Requirements
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None. |
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Sample Handling
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Preservation of the sample is not practical; analysis should begin as soon as possible. Refrigeration to 4oC is recommended to reduce microbiological decomposition of solids. |
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Maximum Holding Time
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7 days (MCAWW, Table 1). |
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Relative Cost
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Less than $50 |
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Sample Preparation Methods
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None. |
