ASTM D4206-96(2018)

Standard Test Method for Sustained Burning of Liquid Mixtures Using the Small Scale Open-Cup Apparatus

SIGNIFICANCE AND USE
4.1 Mixtures of flammable liquids and nonflammable liquids, such as an alcohol and water mixture, are classified by the U. S. Government by the definition of flammable liquid based on a closed-cup flash point method. Thus, mixtures may be classed as flammable even though they do not sustain burning. This test method determines the ability of a liquid mixture to sustain burning and, when used with a closed-cup flash point method, indicates the flammability characteristics of the mixture.
SCOPE
1.1 This test method2 describes a procedure for determining the sustained burning characteristics of mixtures of flammable and nonflammable liquids and to mixtures containing liquids with widely different flash points.  
1.2 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.  
1.3 This standard should be used to measure and describe the response of materials, products, or assemblies to heat and flame under controlled conditions and should not be used to describe or appraise the fire-hazard or fire-risk of materials, products, or assemblies under actual fire conditions. However, results of the test may be used as elements of a fire-hazard assessment or a fire-risk assessment which takes into account all of the factors which are pertinent to an assessment of the fire hazard or fire risk of a particular end use.  
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.

General Information

• Status: Published
• Publication Date: 31-May-2018
• ICS: 87.060.30 - Solvents
• Technical Committee: D01 - Paint and Related Coatings, Materials, and Applications
• Drafting Committee: D01.21 - Chemical Analysis of Paints and Paint Materials

Relations

• Replaces: ASTM D4206-96(2013) - Standard Test Method for Sustained Burning of Liquid Mixtures Using the Small Scale Open-Cup Apparatus
• Effective Date: 01-Jun-2018
• Referred By: ASTM D8254-19 - Standard Test Method for Flash and Fire Points of Asphalt by Cleveland Open Cup Tester
• Effective Date: 01-Jun-2018
• Referred By: ASTM D92-18 - Standard Test Method for Flash and Fire Points by Cleveland Open Cup Tester
• Effective Date: 01-Jun-2018

Overview

ASTM D4206-96(2018) is the Standard Test Method for Sustained Burning of Liquid Mixtures Using the Small Scale Open-Cup Apparatus. Developed by ASTM International, this method determines the ability of a liquid mixture containing flammable and nonflammable liquids to sustain burning. The test is particularly relevant for classifying the flammability characteristics of mixtures-such as alcohol and water-that may be classified as flammable by closed-cup flash point methods but do not actually sustain burning.

This standard provides essential information for fire-hazard and risk assessment, offering a practical tool for engineers, safety professionals, and laboratory specialists involved with paints, coatings, fuels, and allied liquid products. ASTM D4206 complements flash point determinations to provide a more comprehensive evaluation of liquid mixture combustibility under controlled conditions.

Key Topics

• Scope of Testing: This standard specifies a procedure for assessing whether mixtures of flammable and nonflammable liquids can sustain burning, particularly when the components have widely different flash points.
• Apparatus Used: The method uses a small scale open-cup device, typically an aluminum or stainless steel block with a heated concave well, integrated thermometer, a gas jet (test flame), and temperature control mechanisms.
• Methodology:
  • A specified volume of the test mixture is placed in the well of the pre-heated block.
  • The sample is exposed to a standardized flame.
  • The duration and characteristics of burning are observed and recorded.
• Interpretation of Results: A mixture is considered to sustain burning if flames continue for more than 15 seconds after ignition or if burning occurs as the ignition flame is swung away.
• Limitations: This method assesses materials under controlled laboratory conditions. It does not predict material behavior in actual fire scenarios, but can support broader fire-hazard or risk assessments.

Applications

ASTM D4206 is used for:

• Material Classification: Helps regulatory bodies and manufacturers properly classify liquid mixtures according to their sustained burning capabilities, especially mixtures that could be misclassified as flammable or nonflammable by other test methods.
• Hazard Assessment: Provides key data for fire-hazard and fire-risk evaluations of paints, coatings, fuels, and chemical products.
• Regulatory Compliance: Supports compliance with transportation and workplace safety standards, especially when used in combination with closed-cup flash point tests.
• Product Development and Quality Control: Assists manufacturers in verifying the safety and flammability of new formulations and ensuring consistent product behavior.

Typical industries that benefit from this method include chemical manufacturing, transportation, paint and coatings, and industrial safety.

Related Standards

• Closed-Cup Flash Point Methods: These standards, such as ASTM D56 and ASTM D93, measure flash point for flammable liquids but do not determine the ability to sustain burning.
• British Standard BS 3900 Part A-11: The small scale combustibility test upon which this ASTM method is based.
• ASTM D3278: Related to flash point determination using Setaflash closed-cup testers.
• ISO Fire Testing Standards: Provide additional international context for fire and flammability assessments.
• Other ASTM Combustion and Flammability Standards: Useful for complementary hazard evaluation.

Keywords: ASTM D4206, sustained burning, liquid mixtures, open-cup apparatus, flammability testing, fire hazard assessment, paint and coatings safety, chemical regulatory compliance, closed-cup flash point, laboratory fire 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.
Designation: D4206 − 96 (Reapproved 2018)
Standard Test Method for
Sustained Burning of Liquid Mixtures Using the Small Scale
Open-Cup Apparatus
This standard is issued under the fixed designation D4206; 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.
INTRODUCTION
This test method may be used in conjunction with a flash point determination. If the flash point of
a mixture of flammable and nonflammable liquids or liquids of widely different flash points is below
the upper limit of a flammability classification (for example, 100°F specified by the U.S. Department
ofTransportation),thistestmaybeconductedtodeterminethesustainedburningcharacteristicsofthe
mixture.
This test method is a modification of the test for combustibility now incorporated as Schedule 2 of
the “Highly Flammable Liquids and Liquefied Petroleum Gases Regulation, 1972” of the United
KingdomunderTheFactoriesAct,1961,whichisalsoissuedasBritishStandardBS-3900,PartA-11,
Small Scale Test for Combustibility. This sustained burning test was studied and proposed by the
ASTMCoordinatingCommitteeforFlashPointandRelatedProperties.Themajorpurposeofthistest
is similar to that of the British test—to provide a method for determining the sustained burning
characteristics by directly observing this property rather than by deducing them from the flash point.
1. Scope 1.4 This standard does not purport to address all of the
2 safety concerns, if any, associated with its use. It is the
1.1 Thistestmethod describesaprocedurefordetermining
responsibility of the user of this standard to establish appro-
the sustained burning characteristics of mixtures of flammable
priate safety, health, and environmental practices and deter-
and nonflammable liquids and to mixtures containing liquids
mine the applicability of regulatory limitations prior to use.
with widely different flash points.
1.5 This international standard was developed in accor-
1.2 The values stated in inch-pound units are to be regarded
dance with internationally recognized principles on standard-
as standard. The values given in parentheses are mathematical
ization established in the Decision on Principles for the
conversions to SI units that are provided for information only
Development of International Standards, Guides and Recom-
and are not considered standard.
mendations issued by the World Trade Organization Technical
1.3 This standard should be used to measure and describe Barriers to Trade (TBT) Committee.
the response of materials, products, or assemblies to heat and
2. Referenced Documents
flame under controlled conditions and should not be used to
describe or appraise the fire-hazard or fire-risk of materials,
2.1 British Standards:
products, or assemblies under actual fire conditions. However,
BS-3900Part A-11, Small Scale Test for Combustibility
results of the test may be used as elements of a fire-hazard
3. Summary of Test Method
assessment or a fire-risk assessment which takes into account
all of the factors which are pertinent to an assessment of the
3.1 Ablockofaluminumalloy,orothernonrustingmetalof
fire hazard or fire risk of a particular end use.
suitable heat conductivity, with a concave depression (called
thewell)isheatedtotherequiredtemperatureof120°F(49°C).
A standard source of flame, capable of being swung over the
This test method is under the jurisdiction of ASTM Committee D01 on Paint
centerofthewellandatagivendistancefromit,isattachedto
and Related Coatings, Materials, andApplications and is the direct responsibility of
the metal block.
Subcommittee D01.21 on Chemical Analysis of Paints and Paint Materials.
Current edition approved June 1, 2018. Published June 2018. Originally
approved in 1982. Last previous edition approved in 2013 as D4206–96(2013).
DOI: 10.1520/D4206-96R18. Available from British Standards Institute (BSI), 389 Chiswick High Rd.,
McKelvie, A. N., “A Test for Ability to Support Combustion for Liquids LondonW44AL,U.K.,http://www.bsi-global.comorAmericanNationalStandards
Including Paints and Allied Products,” Journal of Oil Co. Chemical Assoc., 1972, Institute (ANSI), 25 W. 43rd St., 4th Floor, New York, NY 10036, http://
Vol 55, pp. 1086–1095. www.ansi.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D4206 − 96 (2018)
block and its well, the gas jet and its positioning, and the
embeddedthermometerareshowninFig.1andarespecifiedin
Annex A1.
NOTE 1—While the Small Scale Open-Cup Tester is generally made of
an aluminum alloy, continued use of it for sustained burning tests may
produce a carbon deposit in the well that may be difficult to remove
without damaging the aluminum well. A stainless steel well may be
cleaned with crocus cloth.
5.1.1 Gage—A metal strip, capable of checking the height
of the gas jet above the top of the well lip (2.2 6 0.1 mm).
5.1.2 Hot Plate,fittedwithatemperature-controllingdevice
or other means of heating the metal block.
5.1.3 Stopwatch, or other suitable timing device.
5.2 Thermometer, 32to230°F(−5to110°C),traceableto
the National Institute of Standards and Technology.
5.3 Graduated Pipet or Hypodermic Syringe, capable of
delivering 2 6 0.1 mL.
6. Preparation of Sample
6.1 Obtainarepresentativesampleoftheproductundertest,
mixing it thoroughly, especially if it has a tendency to layer,
and keep in an airtight container.
6.2 Because of the possibility of loss of volatile
constituents, the sample should receive only the minimum
treatment to assure uniformity. After removing the specimen,
immediately close the sample container tightly to en sure that
no volatile flammable components escape from the container.
FIG. 1 Small Scale Open Cup Apparatus
(Otherwise a new sample may be necessary if further testing is
required.)
3.2 Two millilitres of the product under test are transferred 6.3 Do not open containers unnecessarily. Do not make
transfersunlessthesampletemperatureisat100°F(37.8°C)or
to the well. After the product has reached the stated
temperature, the flame is passed over the well, held there for a
...