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 is a whole volume sample for the analysis of oil and grease._x000D_ This sample is only suitable for gravimetric methods._x000D_ The solvent for this sample is sea water._x000D_ Sample preparation_x000D_ This sample is ready to analyze._x000D_ For calculation purposes, assume the volume of the sample to be 1 L._x000D_ Rinse the bottle well with your extraction solvent including the cap._x000D_ Analyze using gravimetric methods._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)