ASTM C1900-20

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: C1900 − 20
Standard Practice for
Weathering and Evaluation of Laminated Glass
This standard is issued under the fixed designation C1900; 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.
1. Scope D1435Practice for Outdoor Weathering of Plastics
D2244Practice for Calculation of Color Tolerances and
1.1 This practice is intended to cover procedures for the
Color Differences from Instrumentally Measured Color
exposure of laminated glass materials to natural and acceler-
Coordinates
ated weather.
D2565Practice for Xenon-Arc Exposure of Plastics In-
1.2 This practice is limited to the method by which the
tended for Outdoor Applications
material is to be exposed and the general procedure to be
D4459Practice for Xenon-Arc Exposure of Plastics In-
followed. It is intended for use with finished articles of
tended for Indoor Applications
commerce as well as with all sizes and shapes of test
E308PracticeforComputingtheColorsofObjectsbyUsing
specimens.
the CIE System
1.3 Means of evaluation of the effects of weathering will E313Practice for Calculating Yellowness and Whiteness
Indices from Instrumentally Measured Color Coordinates
depend on the intended use for the test material.
G7Practice for Atmospheric Environmental Exposure Test-
1.4 The values stated in SI units are to be regarded as
ing of Nonmetallic Materials
standard. The values given in parentheses after SI units are
G84Practice for Measurement of Time-of-Wetness on Sur-
providedforinformationonlyandarenotconsideredstandard.
faces Exposed to Wetting Conditions as in Atmospheric
1.5 This standard does not purport to address all of the
Corrosion Testing
safety concerns, if any, associated with its use. It is the
G141Guide for Addressing Variability in Exposure Testing
responsibility of the user of this standard to establish appro-
of Nonmetallic Materials
priate safety, health, and environmental practices and deter-
G155Practice for Operating XenonArc LightApparatus for
mine the applicability of regulatory limitations prior to use.
Exposure of Non-Metallic Materials
1.6 This international standard was developed in accor- 3
2.2 ISO Standard:
dance with internationally recognized principles on standard-
ISO 4892-2Plastics — Methods of exposure to laboratory
ization established in the Decision on Principles for the
light sources — Part 2: Xenon-arc lamps
Development of International Standards, Guides and Recom-
mendations issued by the World Trade Organization Technical
3. Terminology
Barriers to Trade (TBT) Committee.
3.1 Definitions:
3.1.1 Fordefinitionsoftechnicaltermspertainingtoglazing
2. Referenced Documents
used in this practice, see Terminology C1036, C1048, and
2.1 ASTM Standards:
C1172.
C1036Specification for Flat Glass
C1048Specification for Heat-Strengthened and Fully Tem-
4. Significance and Use
pered Flat Glass
4.1 Tests conducted in accordance with this practice are
C1172Specification for Laminated Architectural Flat Glass
used to evaluate the stability of laminated glazing materials
D1003Test Method for Haze and Luminous Transmittance
when they are exposed outdoors or used indoors. The relative
of Transparent Plastics
durability of glazing in outdoor use can be very different
depending on the location of the exposure because of differ-
This practice is under the jurisdiction ofASTM Committee C14 on Glass and
ences in ultraviolet (UV) radiation, time of wetness,
Glass Products and is the direct responsibility of Subcommittee C14.08 on Flat
temperature, pollutants, and other factors. It cannot be
Glass.
assumed, therefore, that results from one exposure in a single
Current edition approved Aug. 1, 2020. Published September 2020. DOI:
10.1520/C1900-20.
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 Available from International Organization for Standardization (ISO), ISO
Standards volume information, refer to the standard’s Document Summary page on Central Secretariat, BIBC II, Chemin de Blandonnet 8, CP 401, 1214 Vernier,
the ASTM website. Geneva, Switzerland, http://www.iso.org.
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C1900 − 20
location will be useful for determining relative durability in a 5.1.5 Specimen Holders—Specimen holders shall be in
different location. When comparing exposure results, at a accordance with Practice D1435.
minimum, the locations of exposure are to be as similar as
5.2 Accelerated Weathering Exposure:
possible with regard to critical factors such as the amount and
5.2.1 Accelerated Chamber—Chamber shall comply with
rate of solar radiation deposited on the specimens, temperature
Practice G155 and shall be operated in accordance with the
and humidity levels during exposure. Exposures in several
conditions specified in 10.3.
locationswithdifferentclimatesthatrepresentabroadrangeof
5.2.2 Accelerated Wathering Racks—Theseracksshallbein
anticipated service conditions may be necessary.
accordance with Practice G155 with all portions of a specimen
4.2 Because of year-to-year climatological variations, re- being equidistant from the light source.
sults from a single exposure test cannot be used to predict the
5.3 Instruments for Measuring Climatological Data:
absolute rate at which a material degrades. Several years of
5.3.1 Instruments Used to Measure Ambient Temperature
repeat exposures are needed to get an average test result for a
and Relative Humidity—Instruments and procedures used for
given location.
measurement of ambient temperature and relative humidity
4.3 The results of short-term natural and accelerated expo- shall be in accordance with Practice G7.
sure tests can provide an indication of relative outdoor
5.3.2 Instruments Used to Measure Solar Radiation—
performance, but they should not be used to predict the Instruments and calibration procedures used for measurement
absolute long-term performance of a material. The results of
of total solar radiation, total solar ultraviolet radiation, or
tests conducted under natural exposure for less than twelve narrow band solar ultraviolet radiation shall be in accordance
months will depend on the particular season of the year in
with Practice G7.
which they begin.
6. Sampling
5. Test Sites and Apparatus
6.1 For natural weathering, sampling shall be in accordance
5.1 Natural Weathering Exposure:
with the pertinent considerations outlined in Guide G141 with
5.1.1 The natural test site shall conform to the requirements
a minimum of three specimens per interval.
of Practice G7.
6.2 For accelerated weathering a minimum of three speci-
5.1.2 Unlessotherwisespecified,positionexposureracksso
mens per interval shall be used.
that they face the equator.The angle of the exposure rack shall
be positioned relative to the horizontal conditions that are
7. Test Specimens
being evaluated.
7.1 Exposuretestspecimensshallbeaminimumsizeof152
NOTE 1—Test sites at latitudes less than 23°278 from the equator in
× 152 mm for natural exposure and a minimum size of 76 ×
either hemisphere will have a period during the year when the declination
127 mm for accelerated exposure. They must be capable of
of the sun will exceed the latitude of the site.
being mounted in a holder or applied directly to the racks.
5.1.3 Natural Weather Racks—These racks shall be in
Exposuretestspecimensshouldbelargeenoughthatmounting
accordance with Practice D1435.
edges may be removed where evaluation test results would
5.1.3.1 At-latitude Racks—These racks shall be adjusted
otherwise be affected but small enough to ensure consistent
such that the exposed surfaces are at an angle from the
exposure.
horizontal corresponding exactly to the site latitude angle
(Note 2). 7.2 As far as practical, exposure test specimens shall simu-
late service conditions of an end-use application or shall have
NOTE 2—At-latitude exposure provides maximum annual total solar
prescribed evaluation procedures to allow comparison of
radiant exposure at most nonsubtropical sites. In most non-desert areas,
however, maximum annual ultraviolet-radiant exposure is provided by products.
exposure at an angle of the latitude angle minus 10°.
7.3 The total number of specimens will be determined by
5.1.3.2 45° Racks—These racks shall be adjusted such that
the removal schedule and number of replicates plus file
the exposed surfaces of specimens are at an angle of 45° to the
specimens.Thesefilespecimensshallberetainedatconditions
horizontal.
of23.0 62°Cand50 620%relativehumidity.Theyshallbe
5.1.3.3 90° Racks—These racks shall be adjusted such that
covered with inert wrapping to exclude light exposure during
the exposed surfaces of specimens are at an angle of 90° to the
the exposure and retain period.
horizontal.
5.1.3.4 Horizontal Racks—These racks shall be positioned
8. Exposure Stages
such that the exposed surfaces of the specimens are horizontal
8.1 Use one of the following methods to specify the
(Note 3).
exposure stages at which changes in properties of test speci-
NOTE3—Toprovidemoisturerunoffformosthorizontal-typetestingof
mens are determined.
plastics, 5° south exposure is usually preferred. However, plastic roofing
NOTE 4—The same exposure stage (by whichever method isused) will
membranes, artificial turf, and other plastics that may be exposed at
notnecessarilygivethesamechangesinpropertiesofthetestspecimenat
horizontal in their end-use condition should be exposed at 0° horizontal.
different exposure sites. The exposure states must be regarded as provid-
5.1.4 Materials and Manner of Construction—Test racks
ing only a general indication of the degrees of exposure, and the results
and hardware shall conform to the requirements of Practices
should always be considered in terms of characteristics of the exposure
G7 and D1435. site as well.
C1900 − 20
TABLE 1 Accelerated Weathering Exposure Conditions
8.1.1 Natural Exposure Time—Specify the duration of the
Method A—Outdoor Applications No Spray
exposure in terms of months (1, 3, 6, 12, 15, etc.) or years (1,
Parameter Description
1.5, 2, 3, 4, 5, etc.), unless otherwise instructed.
Practice D2565 Cycle Cycle 1
Black Panel Temperature 64±2°C(145±4°F)
NOTE 5—The results for exposure stages of less than one year will
Relative Humidity 50±5%
depend on the season of the year in which the exposure was made. For
Spray Water None
instance, summer exposures are generally more severe than winter
A 2
Irradiance 0.35±0.02W/m at 340 nm, or
exposures. Seasonal effects are averaged in exposures of several years.
41.5 ± 2.5 W/m from 300 to 400 nm
A
Exposure Duration 3000 h
8.2 Accelerated Exposure Time—Specifythedurationofthe
A
Minimum acceptable levels of irradiance and duration are indicated and shall be
exposure in terms of hours (100, 500, 1000, 3000, etc.) unless
recorded in the report section.
otherwise instructed.
9. Procedure
TABLE 2 Accelerated Weathering Exposure Conditions
Method B—Outdoor Applications With Water Spray
9.1 Mark the test and control specimens to be exposed with
Parameter Description
an identifying number, letter, or symbol so that they may be
Practice D2565 Cycle Cycle 1
identifiedreadilyafterexposure.Specimenmarkingshallbeon
Black Panel Temperature 64±2°C(145±4°F)
Relative Humidity 50±5%
the exterior or No. 1 surface, such that there is no interference
Spray Water De-ionized
with the exposure, testing, or interlayer.
A 2
Irradiance 0.35±0.02W/m at 340 nm, or
41.5 ± 2.5 W/m from 300 to 400 nm
9.2 Natural weathering procedures shall be in accordance
A
Exposure Duration 3000 hours
with Practice D1435. On average, a one-year exposure ap-
A
Minimum acceptable levels of irradiance and duration are indicated and shall be
proximates a Total Ultraviolet (TUV) exposure of 300 6
recorded in the report section.
25 MJ/m at 295 to 385 nm.
9.2.1 All materials are exposed in an unbacked condition.
Specificconditionsofusemayrequiretheglassmaterialtoalso
weatheredconcurrentlytodeterminetheweatheringofglazing
be evaluated with a suitable backing material to conform to
and eliminate those changes from the interlayer or adhesive
projected practice. The effect of backing is highly significant
evaluation.
and may contribute to a change in the weathering performance
9.3.3.2 The specimens shall be exposed in accordance with
of the exposed materials.
Practice D2565 (or ISO 4892-2) and the following conditions
9.2.2 For products intended for external use (for example,
as stated in Table 2.
façade,storefront,window,door),usea26°Northlatitude,45°
9.3.4 Accelerated Weathering Exposure Method C—Indoor
angleofexposure,direct,facingSouth,open-backedmounting.
Applications Only:
9.2.3 For products intended for internal use only (for
9.3.4.1 The purpose of these tests is to determine whether
example, partitions, shower doors, balcony) use a 26° North laminated glazing is durable for indoor use.
latitude, 45° angle of exposure, direct, facing South, open-
9.3.4.2 Specimens passing the requirements of natural or
backed mounting. The specimens may be exposed under a
accelerated outdoor exposure and subsequent testing (Section
3 mm clear glass with visible light trans
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