ASTM D3973-85 (R2003) pdf free.Standard Test Method for Low-Molecular Weight Halogenated Hydrocarbons in Water.
1.1 Prepare, from the stock solutions (8.10), a multicomponent secondary dilution mixture containing approximately 5000 times the expected water concentration of each component, using methyl alcohol as the solvent. If the expected concentration range is unknown, perform a preliminary rangefinding measurement, using an aqueous calibration standard (10.2) containing approximately 100 ug/L.
1.2 Prepare an aqueous calibration standard by injecting 20 μL of the secondary dilution mixture (10.1) into 100 mL water in a volumetric fask.NomE 3- Aqueous calibration standards are not stable and should be discarded after 1 h (8 h if stored with zero headspace).
1.3 Each day, extract and analyze the aqueous calibration standard under conditions identical to the sample procedure. 15 Record the area for each component for calculating results (12.1).
1.4 The analyst must be aware of the linear response range of the electron-capture detector. Using aqueous calibration standards covering a broad concentration range, establish a linear range of the test method. Recheck monthly for each compound and the concentration range of interest. Whenever
responses outside the linear range of the test method are obtained, dilute and reanalyze the sample.
2.1 Weigh 1.50 g of sodium chloride into a clean extraction vial (7.1).
2.2 Pipet 1.0-mL of isooctane into the vial. Open the sample vial, pipet 5.0 mL of sample into the extraction vial, seal the vial and shake vigorously for 1 min. Let stand until the phases separate (about 30 s.).
2.3 Analyze the sample by injecting 3.0 μ of the upper (organic) phase into the gas chromatograph, using the 10-μL syringe (7.3). Be careful not to draw any water droplets into the syringe.
2.4 Record the area of each peak of interest.
3.1 One operator from each of six laboratories determined three concentration levels of bromoform, bromodichloromethane, chlorodibromomethane, chloroform, tetrachloroethylene, and l,1,1-trichloroethane on 3 days. Samples containing all six compounds were prepared as methanol concentrates,sealed in glass ampules and shipped to the participating laboratories. Each laboratory prepared samples by diluting the concentrates into Type II reagent water and matrix water. Two of the matrix waters were waste waters, two were natural surface waters, and two were tap water. Recovery and precision are given in Table 1 for reagent water and in Table 2 for matrix water.ASTM D3973 pdf download.