ASTM D7545-14(2019)e1

Standard Test Method for Oxidation Stability of Middle Distillate Fuels—Rapid Small Scale Oxidation Test (RSSOT)

SIGNIFICANCE AND USE
5.1 The induction period may be used as an indication of the oxidation and storage stability of middle distillate fuel.  
5.2 Compared to some other oxidation and storage stability test methods, this method uses a small sample and gives a result in a short time period.
SCOPE
1.1 This laboratory test method covers a quantitative determination of the stability of middle distillate fuels such as diesel fuels and heating oils, with up to 100 % biodiesel, under accelerated oxidation conditions, by an automatic instrument.
Note 1: This test method is technically equivalent to test method EN 16091  
1.2 This test method is designed for products complying with Specification D975 on Diesel Fuel, Grades No. 1D and 2D; Specification D396 on Burner Fuel, Grades No. 1 and No. 2; Specification D6751 on Biodiesel, B100, and Specification D7467 on Diesel Fuel Oil, B6 to B20.  
1.3 This test method measures the induction period, under specified conditions, which can be used as an indication of the oxidation and storage stability of middle distillate fuels.  
1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
1.5 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.  
1.6 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.

General Information

• Status: Published
• Publication Date: 30-Nov-2019
• ICS: 75.160.20 - Liquid fuels
• Technical Committee: D02 - Petroleum Products, Liquid Fuels, and Lubricants
• Drafting Committee: D02.14 - Stability, Cleanliness and Compatibility of Liquid Fuels

Relations

• Replaces: ASTM D7545-14 - Standard Test Method for Oxidation Stability of Middle Distillate Fuels—Rapid Small Scale Oxidation Test (RSSOT)
• Effective Date: 01-Dec-2019
• Refers: ASTM D975-23a - Standard Specification for Diesel Fuel
• Effective Date: 15-Dec-2023
• Refers: ASTM D7467-23 - Standard Specification for Diesel Fuel Oil, Biodiesel Blend (B6 to B20)
• Effective Date: 01-Oct-2023
• Refers: ASTM D7467-20a - Standard Specification for Diesel Fuel Oil, Biodiesel Blend (B6 to B20)
• Effective Date: 01-Jun-2020
• Refers: ASTM D7467-20 - Standard Specification for Diesel Fuel Oil, Biodiesel Blend (B6 to B20)
• Effective Date: 01-Jan-2020
• Refers: ASTM D396-19a - Standard Specification for Fuel Oils
• Effective Date: 15-Dec-2019
• Refers: ASTM D396-19 - Standard Specification for Fuel Oils
• Effective Date: 01-May-2019
• Refers: ASTM D7467-19 - Standard Specification for Diesel Fuel Oil, Biodiesel Blend (B6 to B20)
• Effective Date: 01-May-2019
• Refers: ASTM D975-19 - Standard Specification for Diesel Fuel Oils
• Effective Date: 01-Feb-2019
• Refers: ASTM D7467-18b - Standard Specification for Diesel Fuel Oil, Biodiesel Blend (B6 to B20)
• Effective Date: 15-Dec-2018
• Refers: ASTM D975-18a - Standard Specification for Diesel Fuel Oils
• Effective Date: 01-Dec-2018
• Refers: ASTM D6751-18 - Standard Specification for Biodiesel Fuel Blend Stock (B100) for Middle Distillate Fuels
• Effective Date: 01-Oct-2018
• Refers: ASTM D396-18a - Standard Specification for Fuel Oils
• Effective Date: 01-Oct-2018
• Refers: ASTM D7467-18a - Standard Specification for Diesel Fuel Oil, Biodiesel Blend (B6 to B20)
• Effective Date: 01-Oct-2018
• Refers: ASTM D7467-18 - Standard Specification for Diesel Fuel Oil, Biodiesel Blend (B6 to B20)
• Effective Date: 01-May-2018

Overview

ASTM D7545-14(2019)e1: Standard Test Method for Oxidation Stability of Middle Distillate Fuels-Rapid Small Scale Oxidation Test (RSSOT) is a globally recognized standard developed by ASTM International. This test method provides a quantitative laboratory procedure to determine the oxidation stability of middle distillate fuels, including diesel fuels and heating oils, containing up to 100% biodiesel, under accelerated oxidation conditions. The test is performed using an automatic instrument, ensuring rapid and reliable results with small sample volumes.

Oxidation stability is a key indicator of a fuel's ability to resist degradation during storage, handling, and use. By measuring the induction period-the time until significant oxidation occurs-this method helps identify the storage and operational reliability of fuels, supporting fuel quality management from production to end use.

Key Topics

• Oxidation and Storage Stability: Measures the induction period under specified accelerated conditions to indicate how stable a middle distillate fuel remains when exposed to air and elevated temperatures.
• Rapid Analysis with Small Sample Size: Compared to traditional stability tests, the RSSOT method uses only a 5 mL sample and delivers results in a short timeframe, making it highly efficient for quality control and research.
• Automatic Instrumentation: Employs specialized oxidation testers capable of precise temperature and pressure control, ensuring repeatable and reproducible results.
• Applicable Fuels: Designed for a wide range of middle distillate fuels, including Diesel Fuel Grades No. 1D and 2D (per ASTM D975), Burner Fuel Grades No. 1 and No. 2 (ASTM D396), Biodiesel (ASTM D6751), and Biodiesel blends (B6 to B20, ASTM D7467).
• Standardization and International Compatibility: Technically equivalent to EN 16091, aligning with international standards for fuel testing.

Applications

The ASTM D7545 rapid oxidation stability test is widely used across the petroleum and biodiesel industries for:

• Quality Assurance and Control: Ensures that incoming and outgoing fuel meets stability requirements, reducing risks of engine deposits, filter clogging, or fuel degradation.
• Fuel Specification Compliance: Supports compliance with industry specifications for diesel, heating oils, and biodiesel products, as referenced in ASTM D975, D396, D6751, and D7467.
• Research and Development: Facilitates the development of advanced fuel formulations by determining the effect of additives, blends, and renewable content on oxidative stability.
• Storage and Distribution: Assesses how fuels will perform over time in storage tanks and supply chains, aiding in inventory management and minimizing waste.
• Regulatory and Trade Purposes: Meets the requirements set by national and international regulations, including the WTO Technical Barriers to Trade (TBT) principles.

Related Standards

For comprehensive fuel quality management, consider these related standards:

• ASTM D975: Specification for Diesel Fuel Oils.
• ASTM D396: Specification for Fuel Oils.
• ASTM D6751: Specification for Biodiesel Fuel Blend Stock (B100).
• ASTM D7467: Specification for Diesel Fuel Oil, Biodiesel Blends (B6 to B20).
• ASTM D4057 and D4177: Methods for sampling petroleum and petroleum products.
• EN 16091: European method for oxidation stability by rapid small-scale oxidation.
• ISO 4259: Precision determination and application in test methods.

By adopting ASTM D7545-14(2019)e1, laboratories and industry stakeholders can ensure reliable assessment of fuel oxidation stability, strengthen fuel quality protocols, and align with international best practices in petroleum and biodiesel testing.

Standards Content (Sample)

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.
´1
Designation: D7545 − 14 (Reapproved 2019)
Standard Test Method for
Oxidation Stability of Middle Distillate Fuels—Rapid Small
Scale Oxidation Test (RSSOT)
This standard is issued under the fixed designation D7545; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
ε NOTE—Editorially updated Footnote 5 and Fig. 1 in December 2019.
1. Scope 2. Referenced Documents
1.1 This laboratory test method covers a quantitative deter- 2.1 ASTM Standards:
minationofthestabilityofmiddledistillatefuelssuchasdiesel D396Specification for Fuel Oils
fuels and heating oils, with up to 100% biodiesel, under D975Specification for Diesel Fuel
accelerated oxidation conditions, by an automatic instrument. D4057Practice for Manual Sampling of Petroleum and
Petroleum Products
NOTE 1—This test method is technically equivalent to test method EN
D4177Practice for Automatic Sampling of Petroleum and
Petroleum Products
1.2 This test method is designed for products complying
D6751Specification for Biodiesel Fuel Blend Stock (B100)
with Specification D975 on Diesel Fuel, Grades No. 1D and
for Middle Distillate Fuels
2D; Specification D396 on Burner Fuel, Grades No. 1 and No.
D7467Specification for Diesel Fuel Oil, Biodiesel Blend
2; Specification D6751 on Biodiesel, B100, and Specification
(B6 to B20)
D7467 on Diesel Fuel Oil, B6 to B20.
2.2 Other Standards:
1.3 This test method measures the induction period, under
CEN/TR 16366:2012Liquid Petroleum Products—Middle
specified conditions, which can be used as an indication of the
DistillatesandFattyAcidMethylEster(FAME)Fuelsand
oxidation and storage stability of middle distillate fuels.
Blends—Round Robin Report on Applicability of Rapid
Small Scale Oxidation Test Method
1.4 The values stated in SI units are to be regarded as
EN 590Automotive Fuels—Diesel—Requirements andTest
standard. No other units of measurement are included in this
Methods
standard.
EN 16091Liquid Petroleum Products—Middle Distillates
1.5 This standard does not purport to address all of the
and FattyAcid Methyl Ester (FAME) Fuels and Blends—
safety concerns, if any, associated with its use. It is the
Determination of Oxidation Stability by Rapid Small
responsibility of the user of this standard to establish appro-
Scale Oxidation Method
priate safety, health, and environmental practices and deter-
ISO 4259Petroleum Products—Determination andApplica-
mine the applicability of regulatory limitations prior to use.
tion of Precision Data in Relation to Methods of Test
1.6 This international standard was developed in accor-
dance with internationally recognized principles on standard-
3. Terminology
ization established in the Decision on Principles for the
3.1 Definitions of Terms Specific to This Standard:
Development of International Standards, Guides and Recom-
3.1.1 break point, n—pressure in the test apparatus which is
mendations issued by the World Trade Organization Technical
10 % below the maximum pressure of the actual test run.
Barriers to Trade (TBT) Committee.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
This test method is under the jurisdiction of ASTM Committee D02 on Standards volume information, refer to the standard’s Document Summary page on
Petroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility of the ASTM website.
Subcommittee D02.14 on Stability, Cleanliness and Compatibility of Liquid Fuels. Available from European Committee for Standardization (CEN), Avenue
Current edition approved Dec. 1, 2019. Published December 2019. Originally Marnix 17, B-1000, Brussels, Belgium, http://www.cen.eu.
approved in 2009. Last previous edition approved in 2014 as D7545–14. DOI: Available from International Organization for Standardization (ISO), 1, ch. de
10.1520/D7545-14R19E01. la Voie-Creuse, CP 56, CH-1211 Geneva 20, Switzerland, http://www.iso.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
´1
D7545 − 14 (2019)
3.1.2 induction period, n—timeelapsedbetweenstartingthe Standards and Technology (NIST) or to a national authority in
heating procedure of the sample vessel and the break point, the country in which the equipment is used or manufactured.
measured in minutes.
7. Reagents and Materials
4. Summary of Test Method 7.1 Solvent for the removal of oxidation residues from the
test vessel. The solvent shall be of suitable purity to leave no
4.1 A 5mL sample is introduced into a pressure vessel
residue on the apparatus. Ethanol of 94% minimum purity has
which is then charged with oxygen to 700kPa at ambient
been found to be suitable. Other solvents, such as a mixture of
temperature. The test is initiated by starting the heater and
equalvolumesoftolueneandacetone,maybeusedifshownto
heating the pressure vessel to a temperature of 140°C.
meet the requirements for the removal of oxidation residues
4.2 The pressure is recorded continuously until the break-
from the test vessel without leaving any residue in the sample
pointisreached.Alternatively,thetestmaybeterminatedwhen
test cup.
a minimum specification requirement is reached.
7.2 Oxygen—Commercially available extra-dry oxygen of
not less than 99.6% purity.
5. Significance and Use
7.3 Lint-free Cleaning Tissue—For sensitive surfaces and
5.1 Theinductionperiodmaybeusedasanindicationofthe
that will not scratch the surface.
oxidation and storage stability of middle distillate fuel.
7.4 “O -ring” Seal—See A1.2.
5.2 Compared to some other oxidation and storage stability
7.5 Temperature Calibration Fluid—Stablemiddledistillate
test methods, this method uses a small sample and gives a
result in a short time period. liquid with a flash point above +60°C and a boiling point
above +150°C.
6. Apparatus
8. Hazards
6.1 General—This test method uses an automatically con-
8.1 (Warning—To provide protection against possible ex-
trolled oxidation tester (see Fig. 1) comprising an oxidation
plosive rupture of the pressure vessel and hazards relating to
pressure vessel containing a test sample cup capable of being
hotandflammablefuels,theapparatusshallbeoperatedbehind
rapidly heated, fitted with a pressure sensor capable of mea-
an appropriate safety shield.)
suring pressures up to 2000kPa and a temperature sensor
capable of reading to 0.1°C.
9. Sampling
6.1.1 Pressure and temperature in the oxidation vessel are
9.1 Sample in accordance with Practice D4057 or D4177.
recorded continuously during the test. The oxidation pressure
vessel is fitted with filling and relief-valves and a means of
10. Preparation of Apparatus
automatically releasing the pressure. The integrated cooling
10.1 Remove the previous sample by means of a pipette or
fan cools the pressure vessel from the test temperature to
similar device.
ambient temperature by a flow of air. See Annex A1 for
10.2 Remove the used “O-ring” seal and discard.
detailed information.
6.2 VolumetricDevice—Cleanandfreefromcontaminations NOTE 2—To avoid contamination of the new test, it is necessary to
discard the used “O-ring” seal, because it might be soaked with oxidation
of previous samples, capable of delivering 5.0mL 6 0.1mL.
products from the previous test.
6.3 Temperature Calibration Equipment—Comprising a
10.3 Wipethetestsamplecup,thesealgrooveandthecover
cover and a temperature calibration sensor (Fig. 2). The
of the test vessel with lint-free cleaning tissue (7.3) soaked
temperature calibration sensor is fixed to a depth of 15mm 6
with solvent until free of gum or other oxidation residues.
0.5mm. The temperature calibration sensor, calibrated to the
10.4 Allow the test sample cup and cover to dry in air and
nearest0.1°C,iscalibratedbyanapprovedcalibrationservice,
visually inspect for cleanliness.
such as one that is traceable to the National Institute of
NOTE 3—Compressed air is generally unsuitable to speed up evapora-
Standards and Technology (NIST) or to a national authority in
tion of solvent because it can contain traces of oil that could contaminate
the country in which the equipment is used or manufactured.
the next test.
6.4 Pressure Calibration Equipment—Comprising a pres-
10.5 Insert a new “O-ring” seal.
surecalibrationsensor(Fig.3).Thepressurecalibrationsensor
11. Calibration
is calibrated to the nearest 10kPa by an approved calibration
service,suchasonethatistraceabletotheNationalInstituteof
11.1 Recalibrate the tester every 12 months for correct
temperature and pressure detection.
11.2 Calibration of Temperature Indicator—Calibrate the
The sole source of supply of the apparatus known to the committee at this time
temperature sensor (A1.6) to the nearest 0.1°C using the
is Anton Paar’s RapidOxy 100 instrument (formerly PetroOxy), available from
temperature calibration equipment (6.3) according to A2.1.
Anton Paar ProveTec GmbH, Ludwig-Erhard-Ring 13,15827 Blankenfelde-
Mahlow, Germany. If you are aware of alternative suppliers, please provide this
11.3 Calibration of Pressure Detector—Calibrate the pres-
information to ASTM International Headquarters. Your comments will receive
sure sensor (A1.5) to the nearest 10kPa, using the pressure
careful consideration at a meeting of the responsible technical committee, which
you may attend. calibration equipment (6.4) according to A2.2.
´1
D7545 − 14 (2019)
1. Safety and insulating hood
2. Screw cap for closing the test container
3. Locking/unlocking mechanism for insulating hood
4. “O-ring” seal for test sample cup
5. Test sample cup
6. Operating panel with display
7. Oxygen inlet
8. Oxygen outlet
FIG. 1 Schematic of Apparatus for Rapid Small Scale Oxidation Test
´1
D7545 − 14 (2019)
1. Calibration cover with duct for temperature calibration sensor
2. Calibration fluid
3. Temperature sensor for block temperature
4. Heating block
5. Immersion depth of temperature calibration sensor and bottom of
calibration cover
6. Seal
7. Temperature calibration sensor
8. Conn
...