ASTM D7619: Particle Counting in Diesel and Other Distillate Fuels

Modern diesel injection systems work with very fine clearances, and particles in the fuel block filters and wear pumps, injectors and pistons. ASTM D7619 is a test method for counting those particles in the laboratory or in the field.

What the standard covers

D7619 uses a specified automatic particle counter to count and size dirt, water droplets and other particles in light and middle distillate fuels and in biofuels such as biodiesel and its blends. It covers 4 µm(c) to 100 µm(c), and results are reported per millilitre in at least the bands of 4, 6 and 14 µm(c), the same sizes used in ISO 4406 codes.

Fuels within its scope include diesel to ASTM D975, aviation turbine fuel to ASTM D1655, biodiesel to ASTM D6751, biodiesel blends to ASTM D7467, and the distillate grades of fuel oil.

The method is for samples, in the laboratory or the field. It is not for counters fitted in the line.

Why the counts matter

• High particle levels block filters and shorten the life of pumps, injectors and other moving parts.

• A rise in the count can show that the fuel has changed in storage or transfer.

• Counts are quick and objective, compared with filtering a sample and weighing the dirt, or judging it by eye.

Water in the count

The counter sees water droplets as particles. For aviation turbine fuel, the standard describes a chemical pretreatment that lets the count exclude free water. For other fuels, a high count may be part water, which is a separate problem handled by coalescers or water separators.

Vens filters and D7619

Vens fuel filter elements and cartridges, in simplex, duplex or cartridge filter housings, can meet fuel cleanliness requirements measured by ASTM D7619, depending on the element and its rating. Tell us the fuel, the flow and the count or code your specification sets.

Related methods: ASTM D8166 for continuous particle monitors, and IP 565 and IP 577 for the cleanliness of aviation turbine fuel.

More: ASTM standards for filters and ASTM D2276 and D5452 for particulates in aviation fuel.

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ASTM is a trademark of ASTM International. Vens Hydroluft is not affiliated with ASTM International. The standards are described in our own words from the scopes ASTM publishes; work to the edition named in your specification. Whether a filter meets a requirement depends on the product, its rating and the conditions of use, so we confirm it for each enquiry. See also our product information disclaimer.