D93_11 Procedure A (16A)
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Ensure that the
sample container is
filled to the volume capacity
requirements specified
in 8.2 of the written standard.
Fill the test cup with the test
specimen to the filling mark
inside of the test cup.
The temperature of the test
cup and the test specimen
shall be at least
18 degrees Celsius
or 32 degrees Fahrenheit below
the expected flash point.
If too much test specimen has
been added to the test cup,
remove the excess using a
syringe or similar device
for withdrawal of fluid.
Place the test cover
on the test cup,
and place the assembly
into the apparatus.
Be sure the locating or locking
device is properly engaged.
If the temperature measuring
device is not already in place,
insert the device
into its holder.
Light the test
flame, and adjust it
to a diameter of 3.2 millimeters
to 4.8 millimeters, 0.126
inches to 0.189 inches, or
switch on the electric igniter
and adjust the
intensity in accordance
with the manufacturer's
instructions.
Warning.
Gas pressure should
not be allowed
to exceed 3 kilopascals, 12
inches of water pressure.
Warning.
Exercise care when
using a gas test flame.
If it should be extinguished,
it will not ignite the vapors
in the test cup and
the gas for the test
flame that then enters the vapor
space can influence the result.
Warning.
The operator should exercise
and take appropriate safety
precautions during the initial
application of the ignition
source, since test specimens
containing low flash material
can give an abnormally strong
flash when ignition source is
first applied.
Warning.
The operator should exercise
and take appropriate safety
precautions during the
performance of these test
methods.
The temperatures attained
during these test methods
up to 370 degrees Celsius,
698 degrees Fahrenheit,
are considered hazardous.
Warning.
As a safety practice when using
automated or manual apparatus,
it is strongly advised,
before heating the test cup
in specimen, to dip
the igniter to check
for the presence of
unexpected volatile material.
Apply the heat at such a
rate that the temperature as
indicated by the temperature
measuring device increases
5 degrees Celsius to
6 degrees Celsius,
9 degrees Fahrenheit to 11
degrees Fahrenheit, per minute.
Turn the stirring device to
90 revolutions per minute
to 120 revolutions
per minute, stirring
in a downward direction.
Warning.
Meticulous attention
to all details relating
to the ignition source,
size of test flame,
or intensity of the
electric igniter,
rate of temperature
increase, and rate
of dipping the ignition source
into the vapor of the test
specimen is desirable
for good results.
If the test specimen is
expected to have a flash
point of 110 degrees Celsius,
or 230 degrees Fahrenheit
or below, apply
the ignition source
when the temperature of the
test specimen is 23 degrees
Celsius plus or minus
5 degrees Celsius,
or 41 degrees Fahrenheit plus
or minus 9 degrees Fahrenheit,
below the expected flash
point, and each time thereafter
at a temperature reading that is
a multiple of 1 degree Celsius
or 2 degrees Fahrenheit.
Discontinue the stirring
of the test specimen,
and apply the ignition source
by operating the mechanism
on the test cover which
controls the shutter so
that the ignition source
is lowered into the vapor
space of the test
cup in 0.5 seconds,
left in its lowered
position for one second,
and quickly raised to
its upward position.
If the test specimen is expected
to have a flash point above 110
degrees Celsius or 230
degrees Fahrenheit,
apply the ignition source
in the manner described
in 11.1.5.1 of the written
standard at each temperature
increase of 2 degrees Celsius,
or 5 degrees Fahrenheit,
beginning at a temperature of
23 degrees Celsius plus or minus
5 degrees Celsius, or 41
degrees Fahrenheit plus or minus
9 degrees Fahrenheit, below
the expected flash point.
Warning.
As a safety practice when using
automated or manual apparatus,
it is strongly advised
that, for an expected flash
point above 130 degrees Celsius,
to dip the igniter every 10
degrees Celsius
throughout the test
until the sample temperature
reaches 28 degrees
Celsius below the
expected flash point,
and then follow the
prescribed dipping procedure.
This practice has
been shown to reduce
the possibility of a
fire and, on average,
not to significantly
affect the result.
A limited study has
shown that this dipping
practice has no observable
effect on test method
repeatability.
When testing materials to
determine if volatile material
contamination is
present, it is not
necessary to adhere
to the temperature
limits for initial
ignition source application
as stated in 11.1.5 of
the written standard.
When testing materials where
the expected flash point
temperature is not known,
bring the material to be tested
and the tester to a temperature
of 15 degrees Celsius
plus or minus 5 degrees Celsius,
or 60 degrees Fahrenheit
plus or minus 10
degrees Fahrenheit.
When the material
is known to be very
viscous at this temperature,
heat the specimen
to a starting
temperature as described
in 8.6 of the written standard.
Apply the ignition
source in the manner
described in 11.1.5.1
of the written standard,
beginning at least 5 degrees
Celsius or 10 degrees
Fahrenheit higher than
the starting temperature.
Flash point results determined
in an unknown expected flash
point mode should be
considered approximate.
This value can be used
as the expected flash
point when a fresh specimen
is tested in the standard mode
of operation.
Record as the
observed flash point,
the reading of the temperature
measuring device at the time
ignition source application
causes a distinct flash
in the interior of the test cup.
The sample is deemed
to have flashed
when a large flame appears
and instantaneously propagates
itself over the entire
surface of the test specimen.
Warning.
For certain mixtures containing
halogenated hydrocarbons,
such as methylene chloride,
or trichloroethylene,
no distinct flash as
defined is observed.
Instead, a significant
enlargement
of the test flame,
not halo effect,
and changing color
of the test flame
from blue to
yellowish-orange occurs.
Continued heating and
testing of the samples
above ambient temperature can
result in significant burning
of vapors outside
of the test cup
and can be a
potential fire hazard.
See appendix X1 and appendix
X2 of the written standard
for more information.
When the ignition
source is a test flame,
the application
of the test flame
can cause a blue halo
or an enlarged flame
prior to the actual flash point.
This is not a flash
and shall be ignored.
When a flash point is detected
on the first application,
the test shall be discontinued,
the result discarded,
and the test repeated with
a fresh test specimen.
The first application
of the ignition source
with the fresh test specimen
shall be 23 degrees Celsius
plus or minus 5 degrees Celsius,
or 41 degrees Fahrenheit
plus or minus 9
degrees Fahrenheit,
below the temperature at which
a flash point was detected
on the first application.
When a flash point is detected
at a temperature which
is greater than 28
degrees Celsius or 50
degrees Fahrenheit
above the temperature
of the first application
of the ignition source,
or when a flash point is
detected at a temperature which
is less than 18 degrees Celsius
or 32 degrees Fahrenheit
above the temperature
of the first application
of the ignition
source, the result
shall be considered
approximate and the test
repeated with a
fresh test specimen.
Adjust the expected flash
point for this next test
to the temperature of
the approximate result.
The first application
of the ignition source
with the fresh test specimen
shall be 23 degrees Celsius
plus or minus 5 degrees Celsius,
or 41 degrees Fahrenheit
plus or minus 9
degrees Fahrenheit,
below the temperature at which
the approximate result was
found.
When the apparatus has cooled
down to a safe handling
temperature, less than
55 degrees Celsius,
130 degrees Fahrenheit, remove
the test cover and the test cup
and clean the apparatus
as recommended
by the manufacturer.
Exercise care when cleaning and
positioning the lid assembly so
not to damage or dislocate
the flash detection
system or temperature
measuring device.
See the manufacturer's
instructions for proper care
and maintenance.
The automated apparatus shall
be capable of performing
the procedure as described in
11.1 of the written standard,
including control
of the heating rate,
stirring of the test specimen,
application of the ignition
source, detection
of the flash point,
and recording the flash point.
Store the automated
apparatus in accordance
with the manufacturer's
instructions.
Warning.
Failure to install the sample
temperature measuring device
correctly when using
automated apparatus
can result in uncontrolled
heating of the test
portion and potentially a fire.
Some automated apparatus
include provisions
to avoid this occurrence.
The apparatus shall follow
the procedural details
described in 11.1.3 through
11.1.8 of the written standard.