EPA-NERL: 375.4: Sulfate by Turbidity
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Official Method Name
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Sulfate (Turbidimetric) |
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Current Revision
| Issued 1971; Editorial Revision 1978 |
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Media
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WATER |
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Instrumentation
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Turbidity |
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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 sample is treated with barium chloride to form a barium sulfate suspension under controlled conditions. The resulting turbidity from the suspension is measured with a nephelometer, and the response is compared to a sulfate standard curve. |
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Scope and Application
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This method determines sulfate in drinking and surface waters; domestic and industrial wastes. |
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Applicable Concentration Range
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1 to 40 mg sulfate/L |
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Interferences
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(A) Turbidity and Color: Turbidity and color natural to the sample can interfere. Interferences can be mitigated by running sample blanks from which barium chloride has been omitted. (B)Silica: Silica at concentrations greater than 500 mg/L will interfere. |
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Quality Control Requirements
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None. |
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Sample Handling
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Refrigerate samples at 4oC. |
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Maximum Holding Time
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28 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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