ASTM: D5072: Radon in Drinking Water
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Official Method Name
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Standard Test Method for Radon in Drinking Water |
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Current Revision
| Current edition approved April 10, 1998. Originally published as D5072-92. |
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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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This test method is based on the scintillation counting of radon-222 and its daughters, a gaseous daughter product of radium-226. An aliquot of unaerated water is drawn into a syringe then gently injected beneath 10 mL of liquid scintillation mix that does not contain an emulsifier. The vials are capped, shaken, and allowed to stand 3 h prior to counting. A commercial liquid scintillation counter is used to count the sample. |
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Scope and Application
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This test method covers the measurement of radon in drinking water in concentrations above 0.04 Bq/L. This test method may be used for absolute measurements by calibrating with a radium-226 standard or for relative measurements by comparing the measurements made with each other. |
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Applicable Concentration Range
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0.04 and greater Bq/L |
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Interferences
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Other radionuclides soluble in the scintillation mix may interfere. Water that is contaminated with high energy beta/gamma emitters, even though they are not soluble in the scintillation mix, may also interfere. These interferences would be rare in drinking water samples but may be observed in some cases. |
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Quality Control Requirements
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Whenever possible, the project leader, as part of the external quality control program, should submit quality control samples to the analyst along with routine samples in such a way that the analyst does not know which of the samples are the quality control samples. These quality control samples, which usually include duplicate and blank samples, should test sample collection and preparation, as well as sample analysis whenever this is possible. In addition, analysts are expected to run internal quality control samples that will indicate to them whether the analytical procedures are in control. Both the external and internal quality control samples should be prepared in such a way as to duplicate the chemical matrix of the routine samples insofar as this is practical. The quality control samples that are used routinely consist of five basic types: blank samples, replicate samples, reference materials, control samples, and "spiked" samples. |
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Sample Handling
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Refer to Practices D 3370 for applicable sampling instructions. Also see U.S. Environmental Protection Agency reports EPA 520 and EPA 600 . Attach the sampling funnel and tube to a faucet with the standard faucet fitting. Slowly turn on the water and allow a steady stream to flow out of the funnel for approximately 2 min. This purges the tube and ensures a fresh sample. Reduce the flow of water and invert the funnel. The flow should be adjusted to a level that does not cause turbulence in the pool of water contained in the funnel. Allow excess water to spill over one edge of the funnel. Examine the hose connection and tubing for air bubbles or pockets. If these are visible, raise or lower the funnel until they are removed. |
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Maximum Holding Time
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Relative Cost
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Unknown |
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Sample Preparation Methods
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