(Equivalent Test Methods: IP 415 and ISO 15167)
EXPLANATION
The mass of particulates present in a fuel is a significant factor, along with size and the nature of the individual particles, in the rapidity with which the fuel filters and other small orifices in fuel systems can become clogged. This test method provides such results. This test method can be used in specifications and purchase documents as a means of controlling particulate contamination levels in the purchased fuels. Several military fuel specifications specify maximum particulate levels in fuels. This test method is suitable for all No. 1 and 2 grades in Specifications ASTM D396, ASTM D975, ASTM D2880, and ASTM D3699, and for grades DMA and DMB in Specification ASTM D2069. This test method is not suitable for fuels whose flash point as determined by Test Methods ASTM D56, ASTM D93, or ASTM D3828 is less than 38° C.
TEST SUMMARY
A measured volume of about 1 L of the fuel sample is vacuum filtered through one or more sets of 0.8 μm membranes.
Each membrane set consists of a tared nylon test membrane and a tared nylon control membrane. Depending upon the level of particulate contaminants in the sample, one or more than two membrane sets may be required. After the filtration has been completed, the membranes are washed with solvent, dried, and weighed.
TEST PRECISION
Where X is the test result, measured to the nearest 0.1 g/m3.
This precision is applicable to particulate contaminant levels between 0 to 25 g/m3 provided that 1 L samples are used and the 1 L is filtered completely. Higher levels of particulates can be measured but are subject to uncertain precision. This test method has no bias.