Membrane testing. Millipore

The ASTM specification for Aviation Turbine Fuels, D1655, calls for the fuel to be visually free of undissolved water, sediment, and suspended matter, and the standard tests for determining the level of dirt/particulate contamination are ASTMD2276/IP216 and D3830. A known quantity of fuel (normally 1 GAL) is passed through standard 37 mm diameter discs of 0.8 micron filter paper under field conditions. The discs are contained in Tenite plastic capsules, or monitors, along with a 34 mm diameter Support Pad. The Gravimetric test is used to give a quantitative assessment of particulate contamination. In this test two membranes with identical (matched) weights are assembled into the monitor under clean laboratory conditions. After testing the laboratory re-weighs the two membranes and establishes the increase in weight by deducting the final weight of the downstream membrane from that of the upstream membrane. The Colormetric test is used as a qualitative assessment of particulate contamination. In this test a single membrane is assembled into the monitor in a clean area at site, and after testing it´s colour is rated against a standard to identity changes in fuel cleanliness. The test is instant and can be performed under site conditions so it is particularly useful in establishing trends in fuel cleanliness. Tested membranes are therefore dried and stored for later comparison.