EPA-NERL: 150.2: pH in Water
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Official Method Name
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pH, Continuous Monitoring (Electrometric) |
|---|---|
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Current Revision
| December 1982 |
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Media
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WATER |
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Instrumentation
|
pH Meter |
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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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The pH of a sample is determined electrometrically using a glass electrode with a reference electrode or a single combination electrode. |
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Scope and Application
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This method continuously determines pH in drinking, surface, and saline waters; domestic and industrial waste waters. |
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Applicable Concentration Range
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None Provided |
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Interferences
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(A) Coating: Inspect electrodes every 30 days to ensure there is not a build-up of oily material or lime on the electrode. Clean electrodes with dilute HCl as required. (B) Temperature: Temperature effects must be compensated for. (C) Sodium: error at pH levels greater than 10 can be reduced or eliminated by using a "low sodium error" electrode. |
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Quality Control Requirements
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None. |
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Sample Handling
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The composition of the water or waste contacting the measuring electrode system must be representative of the total flow from the water body. |
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Maximum Holding Time
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Not Applicable. |
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Relative Cost
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Less than $50 |
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Sample Preparation Methods
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