ASTM D6450-99

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An American National Standard
Designation:D6450–99
Standard Test Method for
Flash Point by Continuously Closed Cup (CCCFP) Tester
This standard is issued under the fixed designation D 6450; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
1. Scope 2. Referenced Documents
1.1 This flash point test method is a dynamic method and 2.1 ASTM Standards:
depends on definite rates of temperature increase. It is one of D 4057 Practice for Manual Sampling for Petroleum and
the many flash point test methods available, and every flash Petroleum Products
point test method, including this one, is an empirical method. D 4177 Practice for Automatic Sampling of Petroleum and
Petroleum Products
NOTE 1—Flash point values are not a constant physical-chemical
E 300 Practice for Sampling Industrial Chemicals
property of materials tested. They are a function of the apparatus design,
2.2 ISO Standards:
the condition of the apparatus used, and the operational procedure carried
out. Flash point can therefore only be defined in terms of a standard test ISO Guide 34 Quality Systems Guidelines for the Produc-
method, and no general valid correlation can be guaranteed between
tion of Reference Materials
results obtained by different test methods or with test apparatus different
ISO Guide 35 Certifications of Reference Material – Gen-
from that specified.
eral and Statistical Principles
1.2 This test method covers the determination of the flash
3. Terminology
point of fuel oils, lube oils, solvents, and other liquids by a
continuously closed cup tester. The measurement is made on a 3.1 Definitions:
test specimen of 1 mL. 3.1.1 flash point, n—the lowest temperature corrected to a
1.3 This test method utilizes a closed but unsealed cup with pressure of 101.3 kPa at which application of an ignition
air injected into the test chamber. source causes the vapors of a specimen of the sample to ignite
1.4 This test method is suitable for testing samples with a momentarily under specified conditions of the test.
flash point from 10 to 250°C. 3.1.1.1 Discussion—Forthepurposeofthistestmethod,the
test specimen is deemed to have flashed when the hot flame of
NOTE 2—Flash point determinations below 10°C and above 250°C can
the ignited vapor causes an instantaneous pressure increase of
be performed; however, the precision has not been determined below and
at least 20 kPa inside the closed measuring chamber.
above these temperatures.
3.2 Definitions of Terms Specific to This Standard:
1.5 If the user’s specification requires a defined flash point
3.2.1 dynamic, adj—the condition in which the vapor above
methodotherthanthistestmethod,neitherthistestmethodnor
the test specimen and the test specimen are not in temperature
any other method should be substituted for the prescribed
equilibrium at the time at which the ignition source is applied.
method without obtaining comparative data and an agreement
from the specifier.
4. Summary of Test Method
1.6 The values stated in SI units are to be regarded as
4.1 The lid of the test chamber is regulated to a temperature
standard. Temperatures are in degrees Celsius, pressure in
at least 18°C below the expected flash point.A1 6 0.1 mLtest
kilo-pascals. The values in parentheses are for information
specimen of a sample is introduced into the sample cup,
only.
ensuring that both specimen and cup are at a temperature at
1.7 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 appro-
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
priate safety and health practices and determine the applica-
Standards volume information, refer to the standard’s Document Summary page on
bility of regulatory limitations prior to use. For specific hazard
the ASTM website.
statements, see Note 6. 3
Available fromAmerican National Standards Institute (ANSI), 25 W. 43rd St.,
4th Floor, New York, NY 10036.
The method of detecting the flash point by monitoring the instantaneous
This test method is under the jurisdiction of ASTM Committee D-2 on pressure increase is covered by a patent. Interested parties are invited to submit
Petroleum Products and Lubricants and is the direct responsibility of Subcommittee information regarding the identification of an alternative(s) to this patented item to
D02.08 on Volatility. ASTMHeadquarters.Yourcommentswillreceivecarefulconsiderationatameeting
Current edition approved Aug. 10, 1999. Published October 1999. of the responsible technical committee, which you may attend.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
D6450–99
least 18°C below the expected flash point, cooling if necessary. 6.1.1 Test Chamber—The test chamber is formed by the
The cup is then raised and pressed onto the lid of specified samplecupandthetemperaturecontrolledlidandshallhavean
dimensions to form the continuously closed but unsealed test overall volume of 4 6 0.2 mL. A metal to metal contact
chamber with an overall volume of 4.0 6 0.2 mL. between the lid and the sample cup ensures good heat contact
4.2 After closing the test chamber, the temperatures of the but shall not be a tight seal to ensure ambient barometric
testspecimenandtheregulatedlidareallowedtoequilibrateto pressure inside the test chamber during the test. Critical
within1°C.Thenthelidisheatedataprescribed,constantrate. dimensions are shown in Fig. A1.2. The pressure inside the
Fortheflashtests,anarcofdefinedenergyisdischargedinside measuring chamber during the temperature increase is moni-
the test chamber at regular intervals.After each ignition, 1.5 6 tored. A seal that is too tight results in a pressure increase
0.5 mLof air is introduced into the test chamber to provide the aboveambientduetothetemperatureandthevaporpressureof
necessaryoxygenforthenextflashtest.Thepressureinsidethe the sample.Apoor heat contact results in a bigger temperature
continuously closed but unsealed test chamber remains at difference between the sample and the heated lid.
ambient barometric pressure, except for the short time during
6.1.2 Sample Cup—The sample cup shall be made of
the air introduction and except at a flash point.
nickel-plated aluminum or other material with similar heat
4.3 After each arc, the instantaneous pressure increase
conductivity. It shall have an overall volume of 4 mLand shall
above the ambient barometric pressure inside the test chamber
be capable of containing 1 6 0.1 mL of sample. The critical
is monitored. When the pressure increase exceeds a defined
dimensions and requirements are shown in Fig. A1.2.
threshold, the temperature at that point is recorded as the
6.1.3 Specimen Temperature Sensor—The specimen tem-
uncorrected flash point.
perature sensor (Fig. A1.1: Ts) shall be a thermocouple
(NiCr-Ni or similar) in stainless steel of 1-mm diameter with a
5. Significance and Use
response time of t(90)=3s.It shall be immersed to a depth of
5.1 The flash point temperature is one measure of the
at least 2 mm into the specimen. It shall have a resolution of
tendency of the test specimen to form a flammable mixture
0.1°C and a minimum accuracy of 6 0.2°C, preferably with a
with air under controlled laboratory conditions. It is only one
digital readout.
of a number of properties that must be considered in assessing
6.1.4 Magnetic Stirring—The apparatus shall have provi-
the overall flammability hazard of a material.
sions for stirring the sample. A rotating magnet outside the
5.2 Flash point is used in shipping and safety regulations to
sample cup shall drive a small stirring magnet, which is
define flammable and combustible materials and classify them.
inserted into the sample cup after sample introduction. The
Consult the particular regulation involved for precise defini-
stirring magnet shall have a diameter of 3 6 0.2 mm and a
tions of these classifications.
lengthof12 61mm.Therotationspeedofthedrivingmagnet
5.3 This test method can be used to measure and describe
shall be between 250 and 270 rev/min.
the properties of materials in response to heat and an ignition
6.1.5 Air Introduction—Theapparatusshallhaveprovisions
source under controlled laboratory conditions and shall not be
for introduction of 1.5 6 0.5 mLof air immediately after each
used to describe or appraise the fire hazard or fire risk of
flash test. The air shall be introduced by a short air pulse from
materials under actual fire conditions. However, results of this
a small membrane compressor by means of a T-inlet in the
test method may be used as elements of a fire risk assessment,
connecting tube to the pressure transducer.
which takes into account all of the factors that are pertinent to
6.1.6 Electricalheatingandthermoelectriccoolingofthelid
an assessment of the fire hazard of a particular end use.
(Fig.A1.1: PE) shall be used to regulate the temperature of the
5.4 Flash point can also indicate the possible presence of
test chamber for the duration of the test. The temperature
highly volatile and flammable materials in a relatively non-
regulation shall have a minimum accuracy of 6 0.2°C.
volatile or nonflammable material, such as the contamination
6.1.7 A high voltage electric arc shall be used for the
of lubricating oils by small amounts of diesel fuel or gasoline.
ignition of the flammable vapor. The energy of the arc shall be
3 6 0.5 mJ (3 6 0.5 Ws) per arc, and the energy shall be
6. Apparatus
applied within 43 6 3 ms.
6.1 Flash Point Apparatus, Continuously Closed Cup
Operation—The type of apparatus suitable for use in this test NOTE 3—Caution: Because samples containing low flash material or
having a flash point below the preset initial temperature can oversaturate
method employs a lid of solid brass, the temperature of which
the vapor inside the chamber and hence prohibit the detection of a flash
is controlled electrically. Two temperature sensors for the
point in the chosen range, the design of the apparatus should incorporate
specimen and the lid temperatures, two electrically insulated
step-wise ignitions in steps of 10°C, following the closing of the
pins for a high voltage arc, and a connecting tube for the
measuring chamber and before the sample reaches the initial temperature
pressuremonitoringandtheairintroductionareincorporatedin
of the test.
the lid. Associated equipment for electrically controlling the
6.1.8 The pressure transducer for the flash point detection
chamber temperature is used, and a digital readout of the
shall be connected to the connecting tube in the lid and shall
specimen temperature is provided. The apparatus and its
have a minimum operational range from 80 to 177 kPa with a
critical elements are shown in Figs. A1.1 and A1.2.
minimum resolution of 0.1 kPa and a minimum accuracy of
60.5 kPa. It shall be capable of detecting an instantaneous
pressure increase above barometric pressure of a minimum of
Continuously closed cup testers meeting these requirements are available from
Grabner Instruments, A-1220 Vienna, Dr. Otto Neurathgasse 1, Austria. 20 kPa within 100 ms.
D6450–99
NOTE 4—The monitoring of the instantaneous pressure increase above
Warming the sample is permitted, but do not heat the sample
barometric pressure is one of several methods used to determine a flash
above a temperature of 18°C below its expected flash point.
inside the test chamber. A pressure increase of 20 kPa corresponds to a
flame volume of approximately 1.5 mL. NOTE 7—Caution: If the sample is suspected of containing volatile
NOTE 5—An automatic barometric correction, which is performed in components, the treatment described in 8.4 and 8.5 should be omitted.
accordance with the procedure described in 12.1, can be installed in the
tester. The absolute pressure reading of the pressure transducer described
9. Quality Control Checks
in 6.1.8 may be used for the correction.
9.1 Verify the performance of the instrument at least once
6.1.9 The introduction of a test portion of 1.0 6 0.1 mL
per year by determining the flash point of a certified reference
shall be accomplished by the use of a pipette or syringe of the
material (CRM) such as those listed inAppendix X1, which is
required accuracy.
reasonably close to the expected temperature range of the
samplestobetested.Thematerialshallbetestedinaccordance
7. Reagents and Materials
with Section 11 of this test method, and the observed flash
7.1 Purity of Reagents—Use only chemicals of purity re-
point obtained in 11.11 shall be corrected for barometric
quested in Table X1.1. Unless otherwise indicated, it is
pressure as described in Section 12. The flash point shall be
intended that all reagents conform to the specifications of the
within the limits stated in Table X1.1.
Committee on Analytical Reagents of the American Chemical
9.2 Once the performance of the instrument has been
Society where such specifications are available. Other grades
verified, the flash point of secondary working standards
may be used, provided it is first ascertained that the reagent is
(SWSs) can be determined along with their control limits.
of sufficient purity to permit its use without lessening the
These secondary materials can then be utilized for more
accuracy of the determination.
frequent performance checks. (see Appendix X1). A perfor-
7.1.1 Anisole—Warning—See Note 6.
mance check with a SWS shall be performed every day the
7.1.2 Dodecane—Warning—See Note 6.
instrument is in use.
7.2 Cleaning Solvents—Use only noncorrosive solvents ca-
9.3 When the flash point obtained is not within the limits
pable of cleaning the sample cup and the lid. Two commonly
stated in 9.1 or 9.2, follow the manufacturer’s instruction for
used solvents are toluene and acetone.
cleaning and maintenance and check the instrument calibration
(see Section 10).After any adjustment, repeat the test in 9.1 or
NOTE 6—Warning: Anisole, dodecane, toluene, acetone, and many
solvents are flammable and are health hazards. Dispose of solvents and 9.2, using a fresh test specimen, with special attention to the
waste material in accordance with local regulations.
procedural details prescribed in this test method.
8. Sampling NOTE 8—Caution: The use of single component verification materials,
such as those listed in Table X1.1, will only prove the calibration of the
8.1 Obtain at least a 50 mL sample from a bulk test site in
equipment. It will not
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