ASTM: D4107: Tritium in Water
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Official Method Name
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Standard Test Method for Tritium in Drinking Water |
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Current Revision
| 1998 |
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Media
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WATER |
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Instrumentation
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Liquid Scintillation Counting |
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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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In this test method, a 100-mL drinking water sample aliquot is treated with a small amount of sodium hydroxide and potassium permanganate, distilled, and a specified fraction of the distillate is collected for tritium analysis. A middle fraction of the distillate is collected for tritium analysis because the early and late fractions are more apt to contain interfering materials for the liquid scintillation counting process. |
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Scope and Application
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This test method covers the determination of tritium in drinking water (as T2O or HTO) by liquid scintillation counting of the tritium beta particle activity.This test method was used successfully with drinking water. It is the user's responsibility to ensure the validity of this test method for waters of untested matrices. |
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Applicable Concentration Range
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0.037 - 555 Bq/mL |
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Interferences
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A reduced counting efficiency may result from quenching in the sample scintillator mixture. Quenching is caused by impurities in the sample, which can inhibit the transfer of energy, or by colored materials, which may absorb some of the emitted light. Corrections for quenching can be made by the use of internal standards or by the ratio method. The approach described in this test method, distillation after alkaline permanganate treatment, eliminates quenching substances, as well as radionuclides which might be present in a volatile chemical form such as radioiodine and radiocarbon. A boiling chip must be used with each distillation to avoid bumping, which can amount to a carry over excursion. Scintillator stock solution or samples exposed to daylight must be dark-adapted. Also, toluene or xylene base scintillators exposed to fluorescent lighting should be dark-adapted for a minimum of 6 h and dioxane base scintillators exposed to fluorescent lighting for 24 h. All fluors should he checked for excitation under lighting conditions being used, and if possible, they should be exposed only to red light. |
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Quality Control Requirements
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Sample Handling
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Collect the sample in accordance with Practices D 3370. Since tritium in drinking water is likely to be in the form of T2O or HTO, there is no need for special handling or preservation. |
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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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