Template For ENG STDS

WORLDWIDE
ENGINEERING Test Procedure GMW3232
STANDARDS

Test Method for Determining the

Flammability of Interior Trim Materials

1 Introduction
Note: Nothing in this standard supercedes applicable laws and regulations.
Note: In the event of conflict between the English and domestic language, the English language shall take
precedence.
1.1 Purpose. This test procedure shall be used to determine the horizontal burn rate of automotive materials.
Burn rate is determined immediately following an exposure for a short duration to a small flame. The small flame
is placed in contact with one (1) edge of the material.
1.1.1 This test procedure defines requirements, testing conditions and reporting requirements for interior raw
materials, including but not limited to textiles, leather, plastics, etc. to support the production part conformance
to government regulations. Aging and statistical requirements address variability seen in some raw materials
including textiles as well as sampling conditions defined in government regulations.
1.1.2 Part requirements and reporting shall conform to government regulations.
1.2 Applicability. The method permits testing of materials and parts of the vehicle interior, individually or in
combination up to a thickness of 13 mm. It is normally only applicable to materials and parts within a 13 mm
range to the passenger compartment air space.
1.2.1 Lot Identification. Each lot of material tested shall remain readily available and identifiable, until the tests
are complete so it may be retrieved in the event of inspection and/or test failure. Each lot of material shall have
a unique identification.
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1.2.2 Use of Incoming Material Test Data. When a source location can demonstrate that their process does
not adversely affect flammability, the source location may use test data from each lot of incoming material.
See 4.1.3 through 4.1.3.2.1.
1.3 Remarks. Not applicable.

2 References
Note: Only the latest approved standards are applicable unless otherwise specified.
2.1 External Standards/Specifications.
49 CFR 571.302 FMVSS 302 ISO 2768 KMVSS Article 95
CONTRAN Resolution 498/14 GB 8410
2.2 GM Standards/Specifications.
GMW3221
2.3 Additional References.
• CG5817 Part Level Flammability Test Result Data Sheet
• GBH (Part number FTTS0170)
• Test Report labelled GMW3232 PROTBEF_eng. available at GM SupplyPower
(https://gmsupplypower.covisint.com/web/portal/home) under Collaborate and Document Library

3 Resources
3.1 Facilities.
3.1.1 Calibration. The test facilities and equipment shall be in good working order and shall have a valid
calibration label.
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3.1.2 Alternatives. Alternative test facilities and equipment may also be used. However, all measuring variables
as specified in this standard shall be determined correctly with respect to their physical definition.
3.2 Equipment.
3.2.1 Test Cabinet. One (1) configuration satisfying these requirements is shown in Appendix A, Figure A1
through Figure A3. The test cabinet consists of a rectangular steel cabinet with internal dimensions of
381 mm ± 1.0 mm long, 203 mm ± 1.0 mm deep and 356 mm ± 1.0 mm high. It shall have a heat resisting glass
observation window, a closable opening to permit insertion of the test specimen mounting fixture and a hole to
accommodate tubing for a gas burner. A 13 mm clearance space around the top of the cabinet, ten (10) 19 mm
diameter holes in the base of the cabinet and legs to elevate the bottom of the cabinet by 10 mm are to be
provided for ventilation.
3.2.2 Conditioning Apparatus. Apparatus for conditioning as required and to the appropriate requirements as
described in GMW3221, (Code A), unless otherwise specified in the relevant material specification.
3.2.3 Oven. Drying oven capable of maintaining the specified temperature within the specified tolerances.
3.2.4 Chemical Fume Cupboard. Chemical fume cupboard suitable for mounting the test cabinet to avoid the
diffusion of combustion products to the laboratory during test. A natural venting hood is permissible, provided
adequate ventilation is assured. Any forced air ventilation shall be the minimum required for venting.
3.2.4.1 Specific Chinese Legal Requirements (GB 8410) Ventilating Cabinet (Reference Deviation
Section). The combustion box shall be placed in a ventilating cabinet. The inner volume of the cabinet shall be
20x to 110x that of the combustion box, and none of the length, width or height may be more than 2.5x than
either of the other two (2) dimensions. At points 100 mm from the front and back of the final position of the
combustion box, measure the speed of air passing the ventilating cabinet. The speed must be
0.10 m/s to 0.30 m/s.
3.2.5 Test Specimen Mounting Fixture. One (1) configuration satisfying these requirements is shown in
Appendix A, Figure A4 and Figure A5. This shall consist of two (2) matching U-shaped frames of metal (e.g.,
aluminum) stock 25 mm wide and 10 mm thick. The interior dimensions of the U-shaped frames shall be 51 mm
wide by 330 mm long. Gauge lines shall be marked (e.g., by slots) on the upper frame 38 mm and 292 mm
respectively from its open end. It is recommended that the frame include markings in 0.5 cm increments up to
25.5 cm for burn distance measurement. This frame can be obtained from GBH (Part number FTTS0170).
In order to support sub size test specimens and those that soften and bend during test, the lower frame shall
have the means to accommodate thin heat resistance wires that span the width of the U-shaped frame at 25 mm
intervals. (Grooves cut into the lower frame to accommodate 0.25 mm, nickel-chrome, thermo wire are
recommended.)
3.2.5.1 Specific Korean Legal Requirements (KMVSS Article 95) (Reference Deviation Section). In order
to support sub size specimens where the maximum available width is 50 mm or less, or in the case of specimens
that show vertical burning caused by sagging at the flaming end, the lower frame shall have the means to
accommodate thin heat resistant wires that span the width of the lower U-shaped frame at 25 mm intervals.
Wires shall not be used for other reasons for certification to KMVSS Article 95. (Grooves cut into the lower frame
to accommodate 0.25 mm, nickel chrome, thermo wire are recommended.)
3.2.6 Support Stand. One (1) configuration satisfying these requirements is shown in Appendix A, Figure A6. A
metal stand to locate and support the test specimen mounting fixture (3.2.5) in the center of the cabinet during
test is required.
3.2.7 Weights. In order to detect when the flame front has progressed to each of the gauge lines, it is
recommended to use lightweight cotton thread counterbalanced with approximately 14 g weights spanning the
full width of the lower U-shaped frame at the gauge lines (Appendix A, Figure A4).
3.2.8 Timer. A calibrated timer with a measurement accuracy of 0.5 s.
3.2.9 Burner. Bunsen burner with a tube of 10.0 mm ± 0.5 mm inside diameter and provided with a gas adjusting
valve to give a flame 38 mm ± 1 mm high when the tube is vertical and the air inlet to the burner is closed.
3.2.10 Gas Source. Gas to provide a flame temperature equivalent to that of natural gas.
3.2.11 Comb. Comb with seven (7) to eight (8) smooth rounded teeth per 25 mm.
3.2.12 Cutting Instruments. Cutting dies or shears for preparation of test specimens.
3.3 Test Vehicle/Test Piece.

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3.3.1 Ideal Specimen Size. Wherever possible, from the available material or component, rectangular test
specimens 355 mm ± 2 mm long and 100 mm ± 2 mm wide, shall be taken. The thickness of the test specimens
shall be that of the single or composite material used in the vehicle, except when the materials or composites
thickness exceeds 13 mm. If material or composite thickness exceeds 13 mm, the test specimens shall be cut
down to 13 mm, measured from the surface of the specimen closest to the passenger compartment air space,
as shown in the figure in S4.2.2 of 49 CFR 571.302 and presented as Figure 1 in this standard for convenience.

Figure 1: Occupant Compartment Air Space

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Note: Material A has a non-adhering interface with material B and is tested separately. Part of material B is within 13 mm of the occupant
compartment air space, and materials B and C adhere at every point of contact; therefore, B and C are tested as a composite. The cut is in
material C as shown, to make a specimen 13 mm thick.

3.3.2 Curved Specimen Size. Where it is not possible to obtain flat test specimens due to surface curvature,
the test specimens shall be cut to not more than 13 mm in thickness at any point. As far as possible, the test
specimens shall be of uniform thickness.
3.3.2.1 Specific Chinese Legal Requirements (GB 8410) (Reference Deviation Section). If the part is bent
so that it is impossible to take a flat sample, take the part that is most flat and make the arch rise of the sample
not more than 13 mm. If the arch rise of the sample exceeds 13 mm, make a standard sample with the same
material, same technique and same structure as the part (356 mm long × 100 mm wide), and let the thickness
be the minimum width but not ˃ 13 mm.
3.3.3 Testing of Smaller Sized Samples.
3.3.3.1 Specific Japanese Legal Requirements (Reference Deviation Section). The minimum acceptable
sample size shall be 25 mm in width and 293 mm in length.
3.3.3.2 Specific Brazilian Legal Requirements (Reference Deviation Section).
(CONTRAN Resolution 498/14). The sample thickness shall correspond to the part/material to be tested but may
not exceed 13 mm. Samples should have a constant section throughout the length.
a. For samples having a width of 3 mm to 60 mm, the length shall be 356 mm ± 2 mm.
b. For samples having a width of 60 mm to 100 mm, the length shall be at least 138 mm.
3.3.3.3 Specific Chinese Legal Requirements (GB 8410) (Reference Deviation Section). Where the shape
and size of the part are insufficient to be made into a standard sample of the specified size, make a sample of
the following minimum size, and keep records per a, b and c in 3.3.3.3.
a. If the part is 3 mm to 60 mm wide, it shall be at least 356 mm long. In this case, make the width of the sample
as close to that of the part as possible.
b. If the part is wider than 60 mm, it shall be at least 138 mm long. In this case, the possible burnt distance is
equivalent to the distance from the first gauge mark to the place where the flame goes out or from the first
gauge mark to the end of the sample as shown in Figure 2.

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c. If the part is 3 mm to 60 mm wide but shorter than 356 mm, or if it is wider than 60 mm but shorter than
138 mm, it shall not be tested per GB 8410. Samples that are narrower than 3 mm shall also not be tested.
3.3.3.4 Specific U.S. Legal Requirements (Reference Deviation Section). Where the shape and size of the
part are insufficient to be made into a standard sample of 100 mm ± 2 mm in width and 355 mm ± 2 mm in
length, it is permissible to cut a sample of the following minimum size, and keep records per a and b in 3.3.3.4.
If these requirements cannot be met, the sample shall be molded into the ideal specimen size per 3.3.4.
a. If the part is 3 mm to 60 mm wide, it shall be at least 356 mm long. In this case, make the width of the sample
as close to that of the part as possible. Or, use molded samples in accordance with 3.3.4.
b. If the part is wider than 60 mm, it shall be at least 138 mm long. In this case, the possible burnt distance is
equivalent to the distance from the first gauge mark to the place where the flame goes out or from the first
gauge mark to the end of the sample as shown in Figure 2. Or, use molded samples in accordance with
3.3.4.
c. If the part has dimensions smaller than described in item a or b, then test molded samples of the raw material
or composite in accordance with 3.3.4 Molded Samples.
3.3.4 Molded Samples. Where sample sizes or shapes restrict the ability to test, molded samples of raw material
or composites shall be made 100 mm ± 2 mm in width and 355 mm ± 2 mm in length with a thickness no thicker
than the thinnest component cross-section from the actual part for which the sample is being substituted.
In sampling the test panels, it shall be ensured the test panels are fully representative of the material or
composite under test.
3.3.5 Multiple Non-Composite Layers. In the case of materials made of superimposed layers of different
materials which are not composite materials, all the layers of the materials included within a depth of 13 mm
from the surface facing towards the passenger compartment air space shall be tested individually.
3.3.6 Test Directionality. For foam, textiles, and composites containing foam or textiles, test specimens shall
be cut from materials or composites both in production direction and perpendicular to this (e.g., warp and weft
direction, longitudinal and lateral direction respectively) if possible. The material direction of the longitudinal and
lateral test specimens must be clearly marked in a manner to identify their original orientation within the roll as
shown in Figure 1. For plastics, painted plastics, or composites not containing foam or textiles, plaques or parts
shall be burnt in only one direction. There shall be no markings to prevent contamination or alteration within the
test area of the specimen.
3.3.7 Sample Sectioning. The requirement concerning transmission of a flame front shall not apply to a surface
created by the cutting of a test specimen for purposes of testing.
3.3.8 Napped or Tufted Samples. Materials or composites with napped or tufted surface shall be placed on a
flat surface and combed twice against the nap with a comb as listed in 3.2.11.

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3.3.9 Plastic. The data of the initial tested color in plaque or part form can be used as surrogate for other colors
in plaque or part form if the first three criteria in 3.3.11 are fulfilled and:
• The burn rate (Bmax and Bstat) is ≤ 72 mm/minute for the tested color.
• Part or plaque thickness is equal to or greater than that of the previously tested part or plaque.
3.3.10 Painted Plastic. The data of the natural plastic, mold-in-color plastic, or the initial tested painted color in
plaque or part form can be used as surrogate for other painted colors in plaque or part form if the first three
criteria in 3.3.11 are fulfilled and:
• The burn rate (Bmax and Bstat) is ≤ 72 mm/minute for the natural plastic, mold-in-color plastic, or for the tested
painted color.
• Part or plaque thickness is equal to or greater than that of the previously tested part or plaque.
3.3.11 Plastic and Painted Plastic Criteria.
• Material is painted, natural or integrally colored plastic.
• Material is painted or made of one (1) layer (no laminate, no composite, no cellular structure).
• Same filler/additive package is used.
• For material level testing of plastics, plaque thickness must be < 2.2 mm.

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Figure 2: Example of Sampling

1 Example, Material Roll.

2 Material Direction.
3 Longitudinal Test Specimens.
4 Lateral Test Specimens.
Note: For specimens cut from direction 3, mark in alternating directions so that the material may be burned with the flame traveling into the
roll (nearest to furthest) or out from the roll (furthest to nearest). For specimens cut from direction 4, mark in alternating directions so that
the material may be burned from left to right or from right to left. See 4.3.1.1.

3.4 Test Time.

Calendar time: Reference Section 4 and Section 5 for timing details
Test time: Reference Section 4 and Section 5 for timing details
Coordination time: Reference Section 4 and Section 5 for timing details
3.5 Test Required Information. Material component information such as vendor name, raw material, production
date and pretreatment shall be reported to the test engineer.
3.6 Personnel/Skills. Personnel trained in accordance with the laboratory accreditation and Standard Operating
Procedure requirements.

4 Procedure
4.1 Preparation.
4.1.1 Specimen Handling. Specimens shall be maintained so that specimens remain free of contaminants prior
to testing. Samples shall not be placed on uncontrolled floors, tables/shelves or transports; Operators are to use
clean gloves; parts are to be transported in clean bags; specimens shall be cut at test site; and other appropriate
practices.
4.1.2 Preparation of Material Level Testing.
4.1.2.1 Conditioning. Immediately prior to testing all test specimens shall be conditioned for a minimum of 24 h
according to GMW3221, Code A.
4.1.2.2 Aging. In addition to tests conducted in the as received condition, all textile, foam, and composites
containing textile or foam materials, shall also be tested for flammability after the following Aged Test Cycle.
Both exposures defined in the Aged Test cycle shall be completed without interruption:
Aged Test Cycle:
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• 48 h ± 1 h at +40 °C ± 3 °C and 93% ± 5% relative humidity.

• 168 h ± 1 h at +90 °C ± 3 °C.

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4.1.2.3 Quantity of Test Specimens for Materials with Directional/Aged Requirements.

4.1.2.3.1 Initial Approval and Arbitration. For initial sample approvals and arbitration purposes, materials that
have directional burn and aged requirements such as textiles, foams, and composites containing textiles or
foams, materials shall test at least 20 specimens except when any individual specimen burn rate exceeds
100 mm/minute. If any individual specimen has a burn rate that exceeds 100 mm/minute, the material does not
meet the flammability requirement and all additional testing shall be terminated. If all burn rates are
< 100 mm/minute, test at least 10 specimens each, from the longitudinal and lateral directions with at least
five (5) specimens tested as received, and at least five (5) specimens tested after having been aged. For each
direction and aging condition, see 5.2.1.2 to determine if additional specimens must be tested.
4.1.2.3.2 Routine Quality Control. For quality control purposes, at least two (2) specimens each from both the
lateral and longitudinal direction in the as received condition shall be tested from each production lot. For the
samples from any one direction, half of the samples shall have the burn direction 180°degrees from the burn
direction of the other half of the samples. For each direction (lateral and longitudinal), test specimens in
alternating directions following the Note in Figure 1. The test shall be performed and the material must comply
with the requirements of 5.2.2 and 5.2.2.1 of this procedure prior to the release of the lot from the manufacturing
facility.
4.1.2.4 Quantity of Test Specimens for Materials with non-Directional/Aged Requirements.
4.1.2.4.1 Initial Approval and Arbitration. For initial sample approvals and arbitration purposes, materials that
do not have directional burn and aged requirements such as plastic, painted plastic materials, or composites not
containing textiles or foams shall test at least five (5) specimens except when any individual specimen burn rate
exceeds 100 mm/minute. If any individual specimen has a burn rate that exceeds 100 mm/minute, the material
does not meet the flammability requirement and all additional testing shall be terminated. See 5.2.1.2 to
determine if additional specimens must be tested.
4.1.2.5 Inherently Flame Resistant Materials. Materials which contain no added flame retardant additives and
exhibit no burn rates in excess of 75 mm/minute during approval testing and after quality control testing of twenty
successive production lots, shall be considered inherently flame resistant. No further production quality control
testing shall be required.
4.1.3 Preparation of Part Level Testing.
4.1.3.1 Conditioning. Immediately prior to testing, all test specimens shall be conditioned for a minimum of 24 h
according to GMW3221, Code A.
4.1.3.2 Aging. In addition to tests conducted in the as received condition, all textile, foam, and composites
containing textile or foam materials, shall also be tested for flammability after the following Aged Test Cycle.
Both exposures defined in the Aged Test cycle shall be completed without interruption:
Aged Test Cycle:
• 48 h ± 1 h at +40 °C ± 3 °C and 93% ± 5% relative humidity.
• 168 h ± 1 h at +90 °C ± 3 °C.
4.1.3.3 Quantity of Test Specimens.
4.1.3.3.1 Approval and Arbitration. For part approvals and arbitration purposes, test at least five (5) specimens
except when any individual specimen burn rate exceeds 100 mm/minute. If any individual specimen has a burn
rate that exceeds 100 mm/minute, the material does not meet the flammability requirement and all additional
testing shall be terminated.
4.1.3.3.2 Directional Burn Parts. It is acceptable to burn in only the worst case burn direction in a textile, foam,
or composite part, if it is known and have proof that worst case direction was chosen. Example of proof can be
material level testing that shows one direction worse than the other. Proof must be clearly shown in compliance
document. If worst direction is unknown, test at least ten (10) specimens each, from the longitudinal and lateral
directions with at least five (5) specimens tested as received, and at least five (5) specimens tested after having
been aged. All burn rates are < 100 mm/minute, see 5.2.1.2 to determine if additional specimens must be tested.
4.1.3.4 Non Flammable Parts. Parts made from materials that do not ignite or burn such as aluminum, steel,
and chrome plated plastic shall not be tested if a validation judgement letter exists which documents agreement
not to test part types.
4.2 Conditions.

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4.2.1 Environmental Conditions. Test shall be conducted at ambient conditions according to

GMW3221 (Code A).
4.2.2 Test Conditions. Deviations from the requirements of this standard shall have been agreed upon. Such
requirements shall be specified on component drawings, test certificates, reports, etc. See Appendix B.
4.3 Instructions.
4.3.1 Sectioning Samples. Test samples are to be cut to the specified dimensions prior to standard conditioning
and any required aging cycles.
4.3.2 Mounting Samples. Mount the test specimen, the surface closest to the passenger compartment air space
facing downward, so that both sides and one end are held by the U-shaped frame, and one end is even with the
open end of the frame. Where the maximum available width of the test specimen is 50 mm or less, so that the
sides of the test specimen cannot be held in the U-shaped frame, place the test specimen in position on the wire
supports with one end held by the closed end of the U-shaped frame. Test specimens shorter than 355 mm shall
be positioned so that one end aligns with the open end of the U-shaped frame.
4.3.2.1 Orientation Identification. Test specimens with an identifiable material orientation, (e.g., warp and weft
direction, longitudinal and lateral direction) should be tested as follows:
• Specimens from any one direction, e.g.; warp and weft direction, longitudinal and lateral direction
(3.3.6 and Figure 1), shall be tested in alternate material directions (right to left versus left to right, and nearest
to farthest versus farthest to nearest). For example; the longitudinal test specimens should be alternatively
tested in both the material and opposite material directions.
• The same is valid for the lateral direction. In this case, using the flame as a reference point, the material
direction of the test specimens shall be alternatively tested from both the right to left and left to right directions.
If the material does not display an identifiable direction, the samples should be tested randomly with respect
to the direction of burn and notation of this exception made on the test report.
4.3.3 Thread Placement. If the two (2) counter balanced cotton threads are used (3.2.7), place threads over the
test specimen at the gauge marks.
4.3.4 Aligning Frames. Place the upper U-shaped frame onto the lower frame so that both frames are matching
in the plan view and the test specimen is held between the two (2) frames under the weight of the upper frame.
If necessary, align the threads in the grooved gauge marks in the upper frame.
4.3.5 Sample Placement. Place the mounted test specimen on the support stand (3.2.6) in a horizontal position
in the center of the test cabinet.
4.3.6 Burner Ignition. Ignite the burner and adjust the flame height to 38 mm ± 1 mm with the air inlet to the
burner closed.
4.3.7 Burner Positioning. Position the burner and the test specimen so that the center of the burner nozzle is
19 mm ± 1 mm under the center of the bottom edge of the open end of the test specimen.
4.3.8 Burner Duration. Expose the test specimen to the flame for 15 s ± 1 s, then remove or extinguish the
burner.
4.3.9 Timer Start. Begin timing when the flame front from the burning test specimen reaches the first gauge
mark (i.e., 38 mm from the open end of the test specimen). If counterweights were used, the first thread will
break allowing the weight to fall.
4.3.10 Time Measurement. Measure the time taken for the flame front to reach the second gauge mark (i.e.,
38 mm from clamped end of test specimen). If counterweights were used, the second thread will break allowing
weight to fall.
• If the flame front does not reach the second gauge mark, time its progress to the point where flaming stops
and measure the length of the flame travel to this point, starting from the first gauge mark.
• If the time taken for the flame front to reach the second gauge mark exceeds four (4) minutes, the test may be
terminated and must be noted as terminated on the test report. The burn distance and elapsed time must be
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measured, and this information must be included on the test report also.
4.3.11 Burn Distance Measurement. Burn distance at the leading edge of the flame must be measured during
the test, preferably using a frame with markings in 0.5 cm increments. Measuring the burn distance after test
has been completed outside of the chamber is not acceptable.

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5 Data
5.1 Calculations.
5.1.1 Burn Rate. Calculate the burn rate from the formula:

𝑆
𝐵= ∗ 60
𝑇

Where:
B = Burn rate in mm (millimeter)/minute
S = Length the flame travels in mm
T = Time in seconds for the flame to travel S mm

5.1.2 Mean. Calculate the mean value from the formula:

𝑛
1
𝑋𝑚 = ∑ 𝑋𝑖
𝑛
𝑖=1

Where:
𝑋𝑚 = Mean value of test results from the same material direction and aging condition
𝑋𝑖 = Individual test result
n = Number of test specimens

5.1.3 Standard Deviation. Calculate the standard deviation from the formula:

𝑛
1
𝜎= √ ∑(𝑋𝑖 − 𝑋𝑚 )2
𝑛−1
𝑖=1

Where:
σ = Standard deviation of test results from same material direction and aging condition
𝑋𝑚 = Mean value of test results from the same material direction and aging condition
𝑋𝑖 = Individual test result
n = Number of test specimens

5.1.4 Statistical Burn Rate. Calculate the statistical burn rate of test results from each material direction and
aging condition using the formula:

𝑩𝒔𝒕𝒂𝒕 = 𝑿𝒎 + 𝟑 ∗ 𝝈

Where:
𝐵𝑠𝑡𝑎𝑡 = Statistical burn rate in mm/minute
𝑋𝑚 = Mean value of test results from the same material direction and aging condition
σ = Standard deviation of test results from same material direction and aging condition
5.1.5 Burn Rate Terminology. Report the burn rate of each of the test specimens tested using the terminology
as defined in Figure 3.
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Figure 3: Zone Distribution

Note 1: 1st gauge mark.

Note 2: 2nd gauge mark.
Note: The zones within the burning area of the U-shaped frame Figure 2 designate the general locations whereby the definitions listed in
5.1.5.1 thru 5.1.5.5 apply.

5.1.5.1 Zone A. Does Not Ignite (DNI). The test specimen does not show any flame after the 15 s ignition period.
5.1.5.2 Zone B. Self-Extinguishing (SE). The test specimen ignites but does not burn to the first timing mark
after 5 minutes (end of Zone B).
5.1.5.3 Zone C. Self-Extinguishing No Burn Rate (SENBR). The test specimen ignites but stops burning before
it has burned for 60 s from the start of timing, and does not burn more than 50 mm from the point where timing
was started.
5.1.5.4 Zone D. Self-Extinguishing with a Burn (SEB) rate of B (see 5.1.1). The test specimen ignites but stops
burning before the flame front exits Zone D. Burn rate B is calculated from the formula in 5.1.1 and rounded up
to the nearest mm/minute.
5.1.5.5 Zone E. Burn rate of B (5.1.1). Burn rate B is calculated from the formula in 5.1.1 and rounded up to the
nearest mm/minute.
5.1.5.6 Specific Chinese Legal Requirements (GB 8410) (Reference Deviation Section). In the cases where
the sample is ignited by the flame and the flame reaches the first gauge mark within 15 s of initial application of
the flame, the sample shall be regarded as not meeting the requirements for burning rate, and the result will be
recorded as E.
5.1.6 Recording Burn Rate. The burn rate shall be recorded:
• As the maximum burn rate of all individual test results from all material directions and aging conditions B Max
(calculated from formula in 5.1.1).
• And as the maximum statistical burn rate B Stat of all sets of test specimens from all material directions and
aging conditions (calculated from formula in 5.1.4 in combination with 5.2.1.4).
• Round up to the nearest mm/minute.
5.2 Interpretation of Results.
5.2.1 Burn Rate Requirements. Unless otherwise specifically agreed, the material under test shall be deemed
to pass only if all test specimens tested conform to the following requirements per 5.2.1.1 through 5.2.1.4.
5.2.1.1 Basic Burn Rate. Material described in 1.2 shall not exhibit a maximum burn rate > 100 mm/minute, if
no lower burn rate is specified in the relevant material specification.
5.2.1.2 Statistical Burn Rate.
For each material direction and each test condition (as received, aged), the highest B stat shall not exceed
100 mm/minute Additionally, the highest Bmax shall not exceed 100 mm/minute.
• Do not include DNI, SE, SENBR in the Bstat calculation as zero. Only non-zero numerical burn rates are to be
included.

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• If there are two or less non-zero numerical burn rates and neither exceeds 75 mm/minute, report the highest
burn rate or the only burn rate as the Bmax.
• Only calculate the Bstat if there are three or more non-zero numerical burn rates.
• If there are either one or two non-zero numerical burn rates and if either or both exceeds 75 mm/minute, burn
an additional five specimens. If there are at least three non-zero numerical burn rates total from all ten
specimens, calculate the Bstat.
5.2.2 Routine Quality Control. Textile and foam materials described in 1.2 shall not burn, nor transmit a flame
front across its surface, at a rate of more than 100 mm/minute, if no lower burn rate is specified in the relevant
material specification.
5.2.2.1 Burn Rate Comparison. Compare burn rates to the burn rates from the initial approval sample. Burn
rates shall not exceed the BStat value for the as received condition and respective burn direction as determined
from the initial approval sample (5.1.4) or 75 mm/minute if the respective BStat value is < 75 mm/minute, or if BStat
could not be calculated from the initial approval sample.
5.3 Test Documentation. With reference to this test procedure, the results of all measurements along with the
maximum burn rate Bmax and the statistical burn rate BStat shall be presented in the test report labeled
GMW3232 PROTBEF_eng available at GM Supply Power
(https://gmsupplypower.covisint.com/web/portal/home) under Collaborate and Document Library and shown in
Appendix C.
5.4 Part Level Test Documentation. With reference to this test procedure, the results of all measurements
along with the maximum burn rate Bmax and the statistical burn rate BStat shall be presented in the test report
labeled GMW3232 PROTBEF_eng available at https://gmsupplypower.covisint.com. Additionally, CG5817 shall
be provided to document parts or assemblies with multiple material/part tests.

6 Safety
This Engineering Standard may involve safety requirements for hazardous materials, the method of operations
and equipment. This standard does not propose to address all the safety issues associated with its use. It is the
responsibility of the user of this standard to ensure compliance with all appropriate safety and health practices.
This would include any specific training that may be required. The safety and health standards include site
specific rules and procedures, company rules and procedures, and Government Standards. Contact shall be
made with the appropriate site Safety and Health personnel for further direction and guidance in these matters.

7 Notes
7.1 Glossary.
Burn Rate: The burn rate, expressed in mm/minute, is the burn distance divided by the time to burn this distance.
Composite Material: A composite material is a material composed of more than one (1) layer intimately held
together at every point of contact by cementing, bonding, cladding, welding etc. When layers are intermittently
held together (e.g., by sewing, high frequency welding, riveting, spot glues, or other methods leaving air space
loose material) the layers are not considered to be composite materials, and must be tested individually.
Directional Burn Material: Material whose burn rate is dependent upon burn direction. Materials with directional
burn requirements include textiles, foams, and composites containing textiles or foams. These materials must
be tested in the lateral and longitudinal direction per Figure 1.
Exposed Side: The Exposed Side is the side which is facing towards the passenger compartment when the
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material is mounted in the vehicle as per the intended component design.

Lot: A lot is a batch, a jumbo roll or a quantity of material which has been produced in a single run from the
same base compound material and is homogeneous in nature.
Non-Directional Burn Material: Material whose burn rate is not dependent upon material burn direction.
Materials without directional burn requirements include plastics, painted plastics, metals, and composites not
containing textiles or foams.
Passenger Compartment Air Space: The Passenger Compartment Air Space is the space within the
passenger compartment that normally contains refreshable air.

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7.2 Acronyms, Abbreviations, and Symbols.

Bmax Maximum Burn Rate
BStat Statistical Burn Rate
DNI Does Not Ignite
FMVSS Federal Motor Vehicle Safety Standards
GSSLT Global Subsystem Leadership Team
KMVSS Korean Motor Vehicle Safety Standards
mm millimeter
SE Self-Extinguishing
SEB Self-Extinguishing with a Burn Rate
SENBR Self-Extinguishing No Burn Rate
US United States

8 Coding System
This standard shall be referenced in other documents, drawings, etc., as follows:
Test to GMW3232. Flammability to meet GMW3232 and must meet all applicable government regulations for
the regions of sale, e.g., FMVSS 302.

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9 Release and Revisions

This standard was originated in May 1999. It was first approved by Global Material Engineering in December
2001. It was first published in December 2001.
Publication
Issue Description (Organization)
Date
1 DEC 2001 Initial publication.
2 AUG 2005 Section 3.2.4 Added word “calibrated” / Section 4.1.6 Reworded “in a manner to identify their
original orientation within the roll shown in Figure 1” / Figure 1: Redrawn for clarification /
Section 5.1 Added “beyond the timing mark”/Section 5.2.1 was “(24 ± 2) h”. / Section 5.3.1.2
Added “and the material must comply with the requirements of paragraphs 6.1.1.2 and
6.1.1.2.1 of this specification”. / Section 5.3.3.1.1 Reworded “an identifiable material
orientation” Added “If the material does not display an identifiable direction, the samples should
be tested randomly with respect to the direction of burn and a notation of this exception made
on the test report.” / Section 6.1.1.2.1 Reworded “value for the as received condition and
respective burn direction as determined from the initial approval sample (6.1.2.4) or 75 mm/min
if the respective Bstat value is less than 75 mm/min or if Bstat could not be calculated from the
initial approval sample.” / Figure 4: Removed sentence: “Tolerance: ± 0.2 mm all dimensions”
(Global Material Engineering)
3 FEB 2007 Section 4.1.9: Added / Section 5.2.2: Text “which do not meet ... 4.1.9.1” added. (Global
Material Engineering)

4 AUG 2011 Section2.1 KMVSS Article 95 and GB8410 added. Section 3.2.1.1. Specific Korean Legal
Requirements added. Section Deviations. Specific Korean Legal Requirements added.
Section 3.2.9 Specific Chinese Legal Requirements added. Section 3.3.2.1 Specific Chinese
Legal Requirements added. Section 3.3.3.4 Specific Chinese Legal Requirements added.
Section 5.1.5.6 Specific Chinese Legal Requirements added. Section Deviations, Specific
Chinese Legal Requirements added.
A complete revision of format. (Textiles/Trim Materials GSSLT)
5 DEC 2016 Updated to current template. (Textiles/Trim Materials Global Subsystem Leadership Team)
6 DEC 2018 Included clarification to supplemental document CG4632 in 5.3. (Materials – Textile/Trim
Materials Global Subsystem Leadership Team (GSSLT))
7 MAR 2020 1.1.1 and 1.1.2 added; 2.3 CG4632 removed, PROTBEF_eng reference corrected, CG5817
added, and supplypower URL updated; Titles added to each section; 3.2.5 added
recommended frame; 3.2.5.1 added wires for vertical burning sample; 3.2.8 updated from
stopwatch to calibrated timer; 3.3.1 Figure added; 3.3.3.2 updated; 3.3.3.4 Specific United
States (US) Legal Requirements added; 3.3.9 updated “50” to “72” for mold in color plastic
parts and text “part or plaque thickness - tested part or plaque” added; 3.3.10 Painted Plastic
added; 3.3.9.1 Criteria updated to 3.3.11; 4.1 added; 4.1.2 for material testing and 4.1.3 for
part testing added; 4.1.2.3 Quantity of Test Specimens for Materials with Directional/Aged
Requirements and 4.1.2.4 Quantity of Test Specimens for Materials with Non-Directional/Aged
Requirements added; 4.1.3.3.2 and 4.1.3.4 added; 4.3.11 added; Removed “arithmetical” from
5.1; Updated Note 1 arrow in Figure 3 Zone Distribution; 5.1.5.2 added five (5) minute time
limit; 5.2.1.2 Updated verbiage; 5.3 updated forms and URL; 5.4 added; 7.1 Glossary added
directional burn material and non-directional burn material; Section 8 updated; Appendix C
PROTBEF_eng Test Report Reference added. (Materials – Textile/Trim Materials GSSLT)
8 FEB 2021 3.3.3.4 Modified item c to direct very small parts to be testing in molded standard size.
(Materials - Textile/Trim GSSLT)

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Appendix A: Recommended Test Equipment Construction

Figure A1: Front View and Side View of Test Cabinet

General Tolerances to ISO 2768 m

Note 1: Burner.

Figure A2: Bottom View of Test Cabinet

Note 1: 10 holes 19 mm Ø.
Notes: Dimensions of housing: All overall dimensions inner dimensions. Window: Glass to be 5.8 mm thick, heat-resistant. Material: Cold
rolled steel 0.9 mm thick except where otherwise noted.
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Figure A3: Test Cabinet Cover

Figure A4: U-frame Assembly with Typical Test Specimen

Note 1: Top U-frame.

Note 2: Slot for Thread.
Note 3: Timing Zone.
Note 4: Thread Guide.
Note 5: Wire.
Note 6: Bottom U-Frame.
Note 7: Thread.
Note 8: Weight.
Note 9: Test Specimen.
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Figure A5: Material Mounting Fixture (Top and Bottom U-Frame)

Note 1: Slot (for thread clearance).

Note 2: Wire guide for thread.
Note 3: 12 Slots each side (for wire supports).

Figure A6: Stand

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Note: Material. Aluminum.

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Appendix B: Recommended Precautionary Measures for Performance of Flammability

Tests to GMW3232

1. The U-shaped frames should always be cleaned prior to each burn test since residual oils; tars, carbon,
etc., tend to form on the frame during each test.
2. Ensure that the support wires, if used, are straight and horizontal so as to prevent sagging of test
specimens.
3. Ensure door always fits flush to the test cabinet (expansion effects can cause poor door fit leading to
drafts).
4. Purge the smoke inside the test cabinet (for example using compressed air from a hand controlled
nozzle) after each test.
5. Before each test ensure as far as possible that the temperature of the test cabinet has not increased
excessively (spare cabinet covers and U-shaped frames, compressed air are useful optional items).
6. Lead flames (a flame that flashes forward of the main burning area) usually occur on vinyl coated fabrics
and must be observed very carefully by the operator.
Note: FMVSS 302 legislation defines lead flame.
7. In performing duplicate tests, test specimens should always be cut from the same area of the material
considering thickness, width, ribs, etc.
8. All ventilation holes must be regularly inspected and cleaned to ensure adequate air circulation in the
cabinet.
9. Particular care must be taken in marking test specimens for identification purposes, since enamels, inks,
etc., could affect test results.
10. Test specimens shall be carefully extinguished after removal from test cabinet, e.g., by dipping in water
or storage in a metal vessel with a metal cover.
11. Test samples are to be cut to the specified dimensions prior to standard conditioning and any required
aging cycles.

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Appendix C: PROTBEF_eng Test Report Reference

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Deviations

The following paragraph shall only be applied at the Korean market:

Dev 3.2.5.1 Specific Korean Legal Requirements (KMVSS Article 95).
Reason:
For the Korean market apply a support wire for sub size sample or vertical burning sample by legal requirements.
No consideration of material soften and bend during test by legal requirements. Test specimens will be taken
from parts in vehicles for compliance test by Korean Government Institute.

The following paragraph shall only be applied at the Japanese market:

Dev 3.3.3.1 Specific Japanese Legal Requirements.
Reason:
For the Japanese market apply a minimum acceptable sample size by legal requirements.

The following paragraph shall only be applied at the Brazilian market:

Dev 3.3.3.2 Specific Brazilian Legal Requirements (CONTRAN Resolution 498/14).
Reason:
For the Brazilian market apply a minimum acceptable sample size by legal requirements.

The following paragraphs shall only be applied at the Chinese market:

Dev 3.2.4.1 Specific Chinese Legal Requirements (GB 8410) Ventilating Cabinet.
Dev 3.3.2.1 Specific Chinese Legal Requirements (GB 8410).
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Dev 3.3.3.3 Specific Chinese Legal Requirements (GB 8410).

Dev 5.1.5.6 Specific Chinese Legal Requirements (GB 8410).
Reason:
For the Chinese market apply a ventilating cabinet, sample preparation method when flat sample is not
available, and minimum acceptable sample size for test by legal requirements. In addition, reporting for the
case of the sample ignited in the flame in 15 s and the flame reaches the 1st gauge mark by legal requirement.

The following paragraph shall only be applied at the United States (US) market:
Dev 3.3.3.4 Specific US Legal Requirements.
Reason:
For the US market apply a minimum acceptable sample size by legal requirements.

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