• Method adopted/last revised:
• Method reapproved: 2020
• REF/ISBN: IP564-2936450
• Status: Current
• First printed in STM books: February 2013

Scope
This standard describes a method for determining the level of dispersed particles in aviation turbine fuel, specifically dirt particles and water droplets in the range from 4 μm to 30 μm, up to a maximum of 40 000 cumulative counts per ml.

NOTE 1 For the purposes of this standard, the terms “% (m/m)” and “% (V/V)” are used to represent respectively the mass fraction and the
volume fraction.

NOTE 2 For the purposes of this method, water droplets are considered as particles and agglomerated particles are detected as a single
obscuration event. Although the projected area of a particle is measured, this is expressed as a diameter for the purposes of this method.

NOTE 3 Annex B describes an optional procedure that may be used to eliminate the effects of water droplets from being counted as particulates.

WARNING – The use of this standard may involve hazardous materials, operations and equipment. This standard does not purport to address all of the safety problems associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health and environmental practices and determine the applicability of regulatory limitations prior to use.