Standard Practice Filtered Open-Flame Carbon-Arc Type Exposures of Plastics

SCOPE
1.1 This practice covers specific variations in test conditions which shall be applicable when Practice G23 is employed for the exposure of plastics. Also covered are the preparation of test specimens, the test conditions best suited for plastics, and the evaluation of test results.
1.2 This standard does not purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.> Note 1-This practice and ISO/DIS4892 are related in title and in technical content. However, the user should note that there may be significant technical differences. ISO/DIS4892 permits the use of different instruments and different procedures among users.

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Historical
Publication Date
09-Jan-1999
Technical Committee
Current Stage
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ASTM D1499-99 - Standard Practice Filtered Open-Flame Carbon-Arc Type Exposures of Plastics
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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: D 1499 – 99
Standard Practice for
Filtered Open-Flame Carbon-Arc Exposures of Plastics
This standard is issued under the fixed designation D 1499; 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 * D 5870 Practice for Calculating Property Retention Index
of Plastics
1.1 This practice covers specific procedures and test condi-
E 691 Practice for Conducting an Interlaboratory Study to
tions that are applicable for exposure of plastics in filtered
Determine the Precision of a Test Method
open-flame carbon-arc devices conducted in accordance with
G 23 Practice for Operating Light-Exposure Apparatus
Practices G 151 and G 152. This practice also covers the
(Carbon-Arc Type) With and Without Water for Exposure
preparation of test specimens, the test condition suited for
of Nonmetallic Materials
plastics, and the evaluation of test results.
G 113 Terminology Relating to Natural and Artificial
NOTE 1—Previous versions of this practice allowed use of both filtered 4
Weathering Tests of Nonmetallic Materials
open-flame and enclosed carbon-arc devices, and referenced carbon-arc
G 141 Guide forAddressingVariability in ExposureTesting
devices in Practice G 23, which described very specific equipment
on Nonmetallic Materials
designs. Practice G 23 is being replaced by Practice G 151, which
G 147 Practice for Conditioning and Handling of Nonme-
describes performance criteria for all exposure devices that use laboratory
light sources, and by Practice G 152, which gives requirements for tallicMaterialsforNaturalandArtificialWeatheringTests
exposing nonmetallic materials in filtered open-flame carbon-arc devices.
G 151 Practice for Exposing Nonmetallic Materials in Ac-
Practice G 23 will be balloted for withdrawal before December 2000.
celerated Test Devices That Use Laboratory Light
Sources
1.2 This practice does not cover enclosed carbon-arc expo-
G 152 Practice for Operating Open-Flame Carbon-Arc
sures of plastics, which had been allowed in Practice D 1499.
Light Apparatus for Exposure of Nonmetallic Materials
Enclosed carbon-arc exposures of nonmetallic materials are
G 153 Practice for Operating Enclosed Carbon-Arc Light
described in Practice G 153. Practice D 5031 describes en-
Apparatus for Exposure of Nonmetallic Materials
closed carbon-arc exposures of paints and related coatings.
G 155 Practice for Operating Xenon-Arc Light Apparatus
NOTE 2—Subcommittee D20.50 is developing a new standard describ-
for Exposure of Nonmetallic Materials
ing exposures of plastics in enclosed carbon-arc devices, and which will
2.2 ISO Standard:
reference Practice G 153.
ISO 4892-4 Plastics—Methods of Exposure to Laboratory
1.3 This standard does not purport to address all of the
Light Sources—Part 4, Open-Flame Carbon Arc Lamp
safety concerns, if any, associated with its use. It is the
responsibility of the user of this standard to establish appro-
3. Terminology
priate safety and health practices and determine the applica-
3.1 The definitions in Terminology G 113 are applicable to
bility of regulatory limitations prior to use.
this practice.
NOTE 3—This practice is technically equivalent to ISO 4892-4.
4. Significance and Use
2. Referenced Documents
4.1 The ability of a plastic material to resist deterioration of
2.1 ASTM Standards: its electrical, mechanical, and optical properties caused by
D 3980 Practice for Interlaboratory Testing of Paint and exposure to light, heat, and water can be very significant for
Related Materials many applications.This practice is intended to induce property
D 5031 Practice for ConductingTests on Paints and Related changes associated with end-use conditions, including the
Coatings and Materials Using Enclosed Carbon-Arc Light effects of sunlight, moisture, and heat. The exposure used in
and Water Exposure Apparatus thispracticeisnotintendedtosimulatethedeteriorationcaused
This practice is under the jurisdiction of ASTM Committee D-20 on Plastics
and is the direct responsibility of Subcommittee D20.50 on Permanence Properties. Annual Book of ASTM Standards, Vol 08.03.
Current edition approved Jan. 10, 1999. Published April 1999. Originally Annual Book of ASTM Standards, Vol 14.02.
published as D 1499 – 50 T. Last previous edition D 1499 – 92a. Available from American National Standards Institute, 11 W. 42nd St., 13th
Annual Book of ASTM Standards, Vol 06.01. Floor, New York, NY 10036.
*A Summary of Changes section appears at the end of this standard.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
D 1499
by localized weather phenomena, such as, atmospheric pollu- 6.3 Follow the procedures described in Practice G 147 for
tion, biological attack, and saltwater exposure. identification and conditioning and handling of test specimens,
4.2 Caution—Variation in results may be expected when and reference materials prior to, during, and after exposure.
operating conditions are varied within the accepted limits of 6.4 Do not mask the face of a specimen for the purpose of
this practice. Therefore, no reference to the use of this practice showing on one panel the effects of various exposure times.
shall be made unless accompanied by a report prepared in Misleading results may be obtained by this method, since the
accordance with Section 9 that describes the specific operating masked portion of the specimen is still exposed to temperature
conditions used. Refer to Practice G 151 for detailed informa- and humidity cycles that in many cases will affect results.
tion on the caveats applicable to use of results obtained in 6.5 Since the thickness of a specimen may markedly affect
accordance with this practice. the results, thickness of test and control specimens shall be
within 610 % of the nominal dimensions.
NOTE 4—Additional information on sources of variability and on
strategies for addressing variability in the design, execution, and data
NOTE 5—This is especially important when mechanical properties are
analysis of laboratory-accelerated exposure tests is found in Guide G 141.
being investigated.
4.3 Reproducibility of test results between laboratories has
6.6 Incident energy at the extremes of the specimen expo-
been shown to be good when the stability of materials is
sure area in older equipment may be only 60 to 70 % of that at
evaluated in terms of performance ranking compared to other
the center. If the irradiance at any position within the exposure
,
6 7
materials or to a control. Therefore, exposure of a similar
area is less than 90 % of the peak irradiance, follow one of the
material of known performance (a control) at the same time as
procedures outlined in Practice G 152 to ensure either equal
the test materials is strongly recommended. It is recommended
radiant exposure or compensation for differences in radiant
that at least three replicates of each material be exposed to
exposure.
allow for statistical evaluation of results.
6.7 Retain a supply unexposed file specimens of all material
4.4 Test results will depend upon the care that is taken to
evaluated.
operate the equipment in accordance with Practice G 152.
6.7.1 When destructive tests are run, ensure that sufficient
Significant factors include regulation of line voltage, freedom
file specimens are retained so that the property of interest can
from salt or other deposits from water, temperature and
be determined on unexposed file specimens each time exposed
humidity control, and conditions of the electrodes.
materials are evaluated.
6.8 Specimens should not be removed from the exposure
5. Apparatus
apparatus for more than 24 h and then returned for additional
5.1 Use filtered open-flame carbon-arc apparatus that con- tests, since this does not produce the same results on all
forms to the requirements defined in Practices G 151 and materials as tests run without this type of interruption. When
G 152. specimensareremovedfromtheexposureapparatusfor24hor
5.2 Unless otherwise specified, the spectral power distribu- more and then returned for additional exposure, report the
tion of the filtered open-flame carbon-arc shall conform to the elapsed time in accordance with Section 9.
requirements in Practice G 152 for carbon-arc with daylight
NOTE 6—Since the stability of the file specimen may also be time-
filters.
dependent, users are cautioned that over prolonged exposure periods, or
where small differences in the order of acceptable limits are anticipated,
6. Test Specimen
comparisonofexposedspecimenswiththefilespecimenmaynotbevalid.
Instrumental measurements are recommended whenever possible.
6.1 The size and shape of specimens to be exposed will be
determined by the specifications of the particular test method
7. Procedure
used to evaluate the effects of the exposure on the specimens;
7.1 Practice G 152 lists several exposure cycles that are
the test method shall be determined by the parties concerned.
used for filtered open-flame carbon-arc exposures of nonme-
Where practical, it is recommended that specimens be sized to
tallic materials. Obtain mutual agreement between all con-
fit specimen holders and racks supplied with the exposure
cerned parties for the specific exposure cycle used. Additional
apparatus. Unless supplied with a specific backing as an
intervals and methods of wetting, by spray or condensation, or
integral part of the test, specimens shall be mounted so that
both, may be substituted upon mutual agreement between the
only the minimum specimen area required for support by the
concerned parties.
holder shall be covered. This unexposed surface must not be
7.1.1 Byhistoricalconvention,thefollowingexposurecycle
used as part of the test area.
has been commonly used for plastics.
6.2 Unless otherwise specified, expose at least three repli-
7.1.1.1 Continuous light with equilibrium uninsulated black
cate specimens of each test and control material.
panel temperature controlled to 63 6 3°C (145 6 9°F),
consisting of the following alternating intervals:
7.1.1.2 102 minutes light only followed by 18 minutes of
Fischer, R., “Results of Round Robin Studies of Light- and Water-Exposure
light with water sprayed on the test specimens.
Standard Practices,” Accelerated and Outdoor Durability Testing of Organic
7.1.1.3 Unless otherwise specified in devices which allow
Materials, ASTM STP 1202, Warren D. Ketola and Douglas Grossman, eds.,
for control of relative humidity, maintain relative humidity at a
American Society for Testing and Materials, Philadelphia, 1993.
Ketola, W., and Fischer, R., “Characterization and Use of Reference Materials
50 6 5 % equilibrium during the light-only interval.
in Accelerated Durability Tests,” VAMAS Technical Report No. 30, available from
NIST, Gaithersburg, MD. NOTE 7—The equilibrium black panel temperature is obtained without
D 1499
a spray period. For light intervals less than 30 min, the maximum black
8.2.2 The minimum exposure time used shall be that nec-
panel temperature may not reach equilibrium.
essary to produce a substantial change in the property of
NOTE 8—The test cycle described in 7.1.1 is also referred to as the
interest for the least stable material being evaluated. An
“102-18 cycle” and may not adequately simulate the effects of outdoor
exposure time that produces a significant change in one type of
exposure.
material cannot be assumed to be applicable to other types of
7.2 It is recommended that all unused spaces in the speci- materials.
8.2.3 The relation between time to failure in an exposure
men exposure area be filled with blank metal panels.
conducted in accordance with this practice and service life in
7.3 Water Purity:
an outdoor environment requires determination of a valid
7.3.1 The purity of water used for specimen spray is very
acceleration factor. Do not use arbitrary acceleration factors
important.Without proper treatment to remove cations, anions,
relating time in an exposure conducted in accordance with this
organics, and particularly silica, exposed panels will develop
practice and time in an outdoor environment because they can
spots or stains that may not occur in exterior exposures.
giveerroneousinformation.Theaccelerationfactorismaterial-
7.3.2 Follow the requirements for water purity described in
dependent and is only valid if it is based on data from a
Practice G 151.
sufficient number of separate exterior and laboratory-
7.3.3 If specimens are found to have deposits or stains after
accelerated exposures so that results used to relate times to
exposure in the apparatus, the water purity must be checked to
failure in each exposure can be analyzed using statistical
determine if it meets the requirements of 7.3.2. On some
methods.
occasions,exposedspecimenscanbecontaminatedbydeposits
from bacteria that can grow in the purified water used for
NOTE 9—An example of a statistical analysis using multiple-laboratory
specimen spray. If bacterial contamination is detected, the
and exterior exposures to calculate an acceleration factor is described by
entire system used for specimen water spray must be flushed Simms. See Practice G 151 for more information and additional cautions
about the use of acceleration factors.
with chlorine and thoroughly rinsed prior to resuming expo-
sures.
8.3 After each exposure increment, evaluate or rate changes
7.3.4 The temperature of water used for specimen spray
in exposed test specimens in accordance with the applicable
should be 16 6 5°C (60.8 6 9°F).
ASTM test methods.
7.3.5 Whentheprecedingwaterpurityrequirementsaremet
NOTE 10—For some materials, changes may continue after the speci-
and there is disagreement between parties on the extent of
men has been removed from the exposure apparatus. Measurements
problems caused by stain or deposit, run referee tests in at least
(visual or instrumental) should be made within a standardized time period
one other laboratory that can meet the water quality require-
or as agreed upon between the interested parties. The standardized time
ments described in 7.3. period needs to consider conditioning prior to testing.
7.4 Some tests for lightfastness are run without any speci-
8.4 Use of results from exposures conducted in accordance
menwetting.Whenthis type of test is required, omittheperiod
with this practice in specifications:
where water is sprayed on specimens.
8.4.1 If a standard or specification for general use requires a
7.5 It is recommended that a control material be exposed at
definite property level
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