3.1 General descriptions for the manual sampling of petroleum products are given in Practice D4057. However, a number of aviation fuel properties are established or affected by trace levels of polar or other compounds. Measurement significance therefore requires that the sample containers not add or adsorb any materials. This practice presents types and preparations of sampling containers found satisfactory for the determination of water separation, copper corrosion, electrical conductivity, thermal stability, lubricity, and trace metal content. The choice of construction materials is an important factor, particularly in the case of aviation turbine fuel, where thermal stability can be degraded by the presence of very low concentrations of copper. The use of copper or copper based alloys shall be eliminated from aviation sampling apparatus. An approval procedure for new containers is also given.

3.2 Two properties, particulate contamination and free water content, involve materials easily removed by any sampling container. These properties should be determined by placing the sample directly into the measuring apparatus and not using containers to transport the sample to the measuring equipment.

3.3 Recommendations in this practice provide guidance for immediate use and for storage of samples. Immediate use involves sample storage for periods less than 24 h.