EPA-NERL: 360.1: Dissolve Oxygen by Membrane Electrode
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Official Method Name
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Oxygen, Dissolved (Membrane Electrode) |
|---|---|
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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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Membrane Electrode |
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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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Dissolved oxygen in a sample is measured using a probe. The most common probes depend on electrochemical reactions. Under steady state conditions, the current or potential is correlated to dissolved oxygen concentrations. |
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Scope and Application
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This method determines dissolved oxygen in water and is recommended as an alternative to the modified Winkler procedure when interferences are present, a non-destructive method is desired, or when continuous monitoring is desired. |
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Applicable Concentration Range
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The range can vary depending on the instrument. 0-20 mg/L is given as an example. |
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Interferences
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(A) Inorganic salts: Salts can change probe response. Use conversion factors to correct for response in saline waters. (B) Reactive gases: Reactive gases like chlorine and hydrogen sulfide can permeate the probe and disrupt operation. Temperature sensitivity: Temperature can effect a probe's output. Generally, a manufacturer provides a compensation factor. |
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Quality Control Requirements
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None. |
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Sample Handling
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See Method 360.2. |
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Maximum Holding Time
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Analyze immediately (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. |
