DOE EML: Ra-06-RC: Radium-226 in Urine and Water
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Official Method Name
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RADIUM-226 IN URINE AND WATER |
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Current Revision
| EML Procedures Manual HASL-300, Volume 1, 28th Ed.(1997) |
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Media
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WATER |
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Instrumentation
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Alpha Scintillation |
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Method Subcategory
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Radiochemical |
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Method Source
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Citation
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Brief Method Summary
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Radium is initially separated from untreated water or urine by coprecipitation with calcium phosphate. Calcium and most other elements are removed by coprecipitation of radium on barium sulfate. Organic material is removed by ignition, silica is removed by volatilization with HF, and the radium-barium sulfate is reprecipitated. Radium-226 in the barium sulfate precipitate is stored to allow the buildup of Rn-222, Po-218, and Po-214. The equilibrated alpha activities are then measured with a scintillation counter. The instrument response is converted to Bq by application of corrections for counter background and efficiency and for self-absorption. Chemical recovery is measured gravimetrically and the Ra-226 activity is equivalent to one-fourth of the total Bq measured. |
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Scope and Application
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Applicable Concentration Range
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None given. |
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Interferences
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(A) Non-target Emitting Isotopes: Other (excluding natural thorium) alpha-emitting isotopes of radium cause interference. (B) Thorium-230: Method fails in the presence of Th-230. (C) Cross contamination: High-level and low-level samples should be processed in independent batches to minimize possibility of cross contamination. |
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Quality Control Requirements
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Reagent blanks must be analyzed with each set of samples. High-level and low-level samples should be processed in independent batches to minimize possibility of cross contamination. |
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Sample Handling
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None given. |
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Maximum Holding Time
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None given. |
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Relative Cost
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$51 to $200 |
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Sample Preparation Methods
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