ASTM D7978-14(2019)
Standard Test Method for Determination of the Viable Aerobic Microbial Content of Fuels and Associated Water—Thixotropic Gel Culture Method

Standard No.

ASTM D7978-14(2019)

Release Date

2019

Published By

American Society for Testing and Materials (ASTM)

Latest

ASTM D7978-14(2019)

Scope

1.1 This test method describes a procedure that can be used in the field or in a laboratory to quantify culturable, viable aerobic microorganisms present as contaminants in liquid fuels, including those blended with synthesized hydrocarbons or biofuels, with kinematic viscosities (at 40 °C) of ≤24 mm2 s-1 and heavy and residual fuels with kinematic viscosities (at 40 °C) of ≤700 mm2 s-1 and in fuel-associated water. 1.1.1 This test method has been validated by an ILS for a range of middle distillate fuels meeting Specifications D975, D1655, ISO 8217 DMA, and NATO F-76.2 1.2 This test method quantitatively assesses culturable, viable aerobic microbial content present in the form of bacteria, fungi, and fungal spores. Results are expressed as the total number of microbial colony forming units (CFU)/L of fuel or total number of CFU/mL of associated water. The number of CFU should not be interpreted as absolute values but should be used as part of a diagnostic or condition monitoring effort; for example, these values can be used to assess contamination as absent, light, moderate, or heavy. NOTE 1—This test method is technically equivalent to IP 613, although the two methods are not currently jointed. 1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.4 This standard does not purport to address all of the safety concerns, if any, 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. 1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

ASTM D7978-14(2019) Referenced Document

• ASTM D1129 Standard Terminology Relating to Water
• ASTM D1655 Standard Specification for Aviation Turbine Fuels
• ASTM D4175 Standard Terminology Relating to Petroleum Products, Liquid Fuels, and Lubricants*， 2023-07-01 Update
• ASTM D4176 Standard Test Method for Free Water and Particulate Contamination in Distillate Fuels (Visual Inspection Procedures)
• ASTM D6469 Standard Guide for Microbial Contamination in Fuels and Fuel Systems
• ASTM D6974 Standard Practice for Enumeration of Viable Bacteria and Fungi in Liquid Fuels—Filtration and Culture Procedures*， 2020-05-01 Update
• ASTM D7464 Standard Practice for Manual Sampling of Liquid Fuels, Associated Materials and Fuel System Components for Microbiological Testing*， 2020-05-01 Update
• ASTM D7847 Standard Guide for Interlaboratory Studies for Microbiological Test Methods*， 2022-07-01 Update
• ASTM D975 Standard Specification for Diesel Fuel Oils
• ASTM E2756 Standard Terminology Relating to Antimicrobial and Antiviral Agents*， 2019-11-01 Update
• ISO 8217 Petroleum products - Fuels (class F) - Specifications of marine fuels

ASTM D7978-14(2019) history

• 2019 ASTM D7978-14(2019) Standard Test Method for Determination of the Viable Aerobic Microbial Content of Fuels and Associated Water—Thixotropic Gel Culture Method
• 2014 ASTM D7978-14 Standard Test Method for Determination of the Viable Aerobic Microbial Content of Fuels and Associated Water—Thixotropic Gel Culture Method