Description_x000D_ General description_x000D_ This proficiency testing sample is produced in accordance with ISO/IEC 17043:2010. All information regarding the use of this material can be found in the reporting packet supplied for each sample._x000D_ Preparation Note_x000D_ This vial contains a concentrate of a blended gasoline from three different sources and diesel fuel oil No. 2 in pentane for analysis by TNRCC Method 1005._x000D_ When prepared according to instructions, the concentration of each analyte will be less than 100 mg/L._x000D_ The packsize on this sample has recently changed from 2ML to 1.2ML. This change does not affect the performance of the proficiency test._x000D_ Sample preparation_x000D_ To prepare solution, fill a 40-mL voa vial to volume with carbon-filtered reagent-grade water at room temperature._x000D_ Remove enough water to allow for the addition of extraction solvent._x000D_ Open vial PE1619-1.2ML and immediately withdraw 40 μL with a gas tight syringe._x000D_ Quickly inject the 40 μL aliquot below the surface of the reagent water in the voa vial._x000D_ Add the extraction fluid._x000D_ Mix the sample by inverting the flask three times only (excessive shaking results in loss of volatiles) and analyze immediately. Assume a 40mL sample for calculation purposes._x000D_ Note this is a 1:1000 dilution and other dilutions are acceptable._x000D_ Other Notes_x000D_ Proficiency testing samples are presented as single blind. No values for the samples are released unti the testing period concludes. Values of analytes vary lot to lot._x000D_ Proficiency Testing Schedule (2020-2021)_x000D_ Wastewater_x000D_ WP20-1 January 15 - February 28, 2020_x000D_ WP20-2 March 25 - May 8, 2020_x000D_ WP20-3A May 13 - June 26, 2020_x000D_ WP20-3B July 8 - August 21, 2020_x000D_ WP20-4 September 23 - November 6, 2020_x000D_ WP20-5 November 25 - January 8, 2021_x000D_ WP21-1 January 13 - February 26, 2021_x000D_ WP21-3 July 7 - August 20, 2021_x000D_ Quick-Turn Study - (non-scheduled proficiency test that is available at any time)