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: E136 − 19a An American National Standard

Standard Test Method for

Assessing Combustibility of Materials Using a Vertical Tube
Furnace at 750°C1
This standard is issued under the fixed designation E136; 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 (´) indicates an editorial change since the last revision or reapproval.
This standard has been approved for use by agencies of the U.S. Department of Defense.

1. Scope* organic content; (3) the exposure temperature; (4) the air
1.1 This fire-test-response test method covers the determi- supply; (5) the location of thermocouples.
nation under specified laboratory conditions of the combusti- 1.3 This test method includes two options, both of which
bility of building materials. Materials passing this test are use a furnace to expose test specimens of building materials to
typically classified as noncombustible materials. a temperature of 750°C (1382°F).
1.2 Limitations of this fire-test response test method are 1.3.1 The furnace for the apparatus for Option A consists of
shown below. a ceramic tube containing an electric heating coil, and two
1.2.1 This test method does not apply to laminated or coated concentric vertical refractory tubes.
materials. 1.3.2 The furnace for the apparatus for Option B (Test
1.2.2 This test method is not suitable or satisfactory for Method E2652) consists of an enclosed refractory tube sur-
materials that soften, flow, melt, intumesce or otherwise rounded by a heating coil with a cone-shaped airflow stabilizer.
separate from the measuring thermocouple. 1.4 This test method references notes and footnotes that
1.2.3 This test method does not provide a measure of an provide explanatory information. These notes and footnotes,
intrinsic property. excluding those in tables and figures, shall not be considered as
1.2.4 This test method does not provide a quantitative requirements of this test method.
measure of heat generation or combustibility; it simply serves
as a test method with selected (end point) measures of 1.5 The values stated in SI units are to be regarded as
combustibility. standard. The values given in parentheses are for information
1.2.5 The test method does not measure the self-heating only.
tendencies of materials. 1.6 This standard is used to measure and describe the
1.2.6 In this test method materials are not being tested in the response of materials, products, or assemblies to heat and
nature and form used in building applications. The test speci- flame under controlled conditions, but does not by itself
men consists of a small, specified volume that is either (1) cut incorporate all factors required for fire-hazard or fire-risk
from a thick sheet; (2) assembled from multiple thicknesses of assessment of the materials, products, or assemblies under
thin sheets; or (3) placed in a container if composed of granular actual fire conditions.
powder or loose-fiber materials.
1.2.7 Results from this test method apply to the specific test 1.7 Fire testing is inherently hazardous. Adequate safe-
apparatus and test conditions and are likely to vary when guards for personnel and property shall be employed in
changes are made to one or more of the following: (1) the size, conducting these tests.
shape, and arrangement of the specimen; (2) the distribution of 1.8 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-
1
This test method is under the jurisdiction of ASTM Committee E05 on Fire priate safety, health, and environmental practices and deter-
Standards and is the direct responsibility of Subcommittee E05.23 on Combustibil- mine the applicability of regulatory limitations prior to use.
ity.
1.9 This international standard was developed in accor-
Current edition approved Dec. 15, 2019. Published January 2020. Originally
approved in 1958. Last previous edition approved in 2019 as E136 – 19 DOI: dance with internationally recognized principles on standard-
10.1520/E0136-19A. ization established in the Decision on Principles for the

*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
 E136 − 19a
Development of International Standards, Guides and Recom- 5. Significance and Use
mendations issued by the World Trade Organization Technical 5.1 Materials that pass this test by complying with the
Barriers to Trade (TBT) Committee. criteria in Section 15 are typically classified as noncombustible
2. Referenced Documents materials.
2.1 ASTM Standards:2 5.2 While actual building fire exposure conditions are not
D1929 Test Method for Determining Ignition Temperature duplicated, this test method will assist in indicating those
of Plastics materials which do not act to aid combustion or add appre-
D3174 Test Method for Ash in the Analysis Sample of Coal ciable heat to an ambient fire.
and Coke from Coal 5.3 Materials passing the test are permitted limited flaming
E84 Test Method for Surface Burning Characteristics of and other indications of combustion.
Building Materials
E136 Test Method for Assessing Combustibility of Materials 6. Apparatus for Option A
Using a Vertical Tube Furnace at 750°C 6.1 The test apparatus shown in Fig. 1, shall be used for
E176 Terminology of Fire Standards Option A and shall consist primarily of the following:
E2652 Test Method for Assessing Combustibility of Mate- 6.1.1 Refractory Tubes—Two concentric, refractory tubes,
rials Using a Tube Furnace with a Cone-shaped Airflow 76 and 102 mm (3 and 4 in.) in inside diameter and 210 to 250
Stabilizer, at 750°C mm (81⁄2 to 10 in.) in length, with axes vertical, and with heat
2.2 ISO Standard:3 applied by electric heating coils outside of the larger tube. A
ISO 871 Plastics – Determination of ignition temperature controlled flow of air is admitted tangentially near the top of
using a hot-air furnace the annular space between the tubes and passes to the bottom
ISO 1182 Noncombustibility Test for Building Materials of the inner tube. The outer tube rests on a refractory bottom
ISO 13943 Fire Safety – Vocabulary and the inner tube rests on three spacer blocks so as to afford
2.3 Other Standard: a total opening under the inner tube equal to or greater than that
BS 476 Combustibility Test of Materials3 of the annular space. The refractory bottom plate has a
3. Terminology removable plug for cleaning.
6.1.2 Transparent Cover—A transparent cover of heat-
3.1 Definitions—For definitions of terms found in this test resistant glass or other transparent material shall be provided
method, refer to Terminology E176 and ISO 13943. In case of over the top of the inner tubes. The cover shall have a circular
conflict, the definitions given in Terminology E176 shall opening 28.7 6 0.8 mm (11⁄8 6 1⁄32 in.) centered over the axis
prevail. of the tubes. This opening has an area of 645 mm2 (1.0 in.2).
The cover shall be in two equally-sized, movable parts.
4. Summary of Test Method
6.1.3 Thermocouples and an automatically recording device
4.1 This test method uses a furnace to expose building shall be provided. The thermocouples shall be located as
materials to a temperature of 750°C (1382°F) until failure follows:
occurs or for at least 30 min. 6.1.3.1 Thermocouple T1 is located in the center of the air
4.2 This test method offers the choice of two options: space between the two concentric, refractory tubes; approxi-
Option A (Sections 6 through 9) and Option B (Test Method mately 204 mm (8 in.) down from the top of the 102-mm
E2652). (4-in.) diameter tube (Note 1).
6.1.3.2 Thermocouple T3 is located at the approximate
4.3 The furnace for Option A consists of two concentric
geometric center of the specimen.
vertical refractory tubes.
6.1.3.3 Thermocouple T4 is located on the surface, in
4.4 The furnace for Option B (Test Method E2652) consists contact with the test specimen; in the same horizontal plane as
of an enclosed refractory tube surrounded by a heating coil T 3.
with a cone-shaped airflow stabilizer. 6.1.3.4 Thermocouples T1 , T3 and T4 shall have a time
4.5 Thermocouples are used to assess the temperature in- constant (time to reach 63.2 % of the furnace air temperature of
creases resulting from combustion of the building material. 750°C (1382°F)) of 5 to 10 s (Note 2).
4.6 Visual observation is used to assess the occurrence of NOTE 1—Thermocouple T1 is used for better regulation of the tempera-
flaming. ture of the air in the furnace space.
NOTE 2—Ungrounded, metallic-sheathed thermocouples of 1-mm di-
4.7 Section 15 is the report and acceptance criteria section ameter have been found to meet the time constant requirements.
for this test method (both options). 6.2 Specimen Holder—The specimen holder for solid test
specimens shall be as shown in Fig. 2.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or 6.2.1 Test specimens in granular or powder form shall be
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM contained in thin-wall, open-top vessels of inert materials
Standards volume information, refer to the standard’s Document Summary page on
whose outside dimensions conform to the test specimen shape
the ASTM website.
3
Available from American National Standards Institute (ANSI), 25 W. 43rd St., and maximum size specified in 7.2. These vessels shall have
4th Floor, New York, NY 10036, http://www.ansi.org. walls of either solid or mesh construction.

2
 E136 − 19a

NOTE 1—Inch-Pound Equivalents

in. 3 4 6 10 103⁄4 1 in.2 No. 16

Awg
2
mm 76 102 152 254 273 6.4 cm 1.29

FIG. 1 Cross Section of Furnace Assembly

6.3 Test Specimen Location—During the test, the geometric 8.2.2 The test apparatus shall not be exposed to drafts or any
center of the test specimen shall be located at the geometric other form of direct sunlight or artificial illumination which
center 63 mm (61⁄8 in.) of the 76-mm (3-in.) diameter tube. would adversely affect the observation of flaming inside the
furnace.
7. Test Specimens for Option A 8.2.3 The room temperature shall not change by more than
7.1 The test specimens for Option A shall comply with 7.2 3°C(5°F) during a test.
through 7.5. 8.3 Air Flow—Provide an external air source to supply clean
7.2 All test specimens shall be 38 by 38 by 51 6 2.5 mm air through a metal tube located near the top of the test
(1.5 by 1.5 by 2.0 6 0.1 in.). apparatus, tangentially between the annular spaced ceramic
tubes. The air shall be supplied at a steady and controllable rate
7.3 The test specimens shall be dried at 60 6 3°C
of 0.0027 m3/min (0.10 ft3/min) 6 20 %, which will give an air
(140 6 5°F) for not less than 24 h but no more than 48 h.
flow of 3 m (10 ft)/min past a loaded test specimen in the
7.4 Test specimens shall then be placed in a desiccator to furnace at 750°C (1382°F). Measure the air at room
cool at least 1 h before testing. temperature, as specified in 8.2.1 and meter by a rotameter or
7.5 Not less than four identical specimens shall be tested. other metering device in line with the metal tube.
8.4 Stabilized Furnace Temperature—Prior to the initial
8. Procedure for Option A heating period insert a thermocouple, T2, into the furnace from
8.1 The procedure for Option A shall comply with 8.2 the top and place it where the geometric center of the test
through 8.11. specimen will be during the test. Use this thermocouple to
8.2 Test Room Setup: establish the stabilized furnace temperature.
8.2.1 Conduct the test at room conditions of 21 6 3°C 8.5 Test Furnace Setup—Prepare the furnace by bringing the
(70 6 5°F). temperature of thermocouple T2, located in the furnace at the

3
 E136 − 19a

FIG. 2 Specimen Holder for Solid Specimens

position to be occupied by the geometric center of the minute. The final temperature reading shall be recorded as the
specimen, to a temperature of 750 6 5.5°C (1382 6 10°F). maximum temperature.
Maintain the temperature in the unloaded furnace for at least 15
8.8 Throughout the test make and record visual observations
min to ensure stability.
on the test specimens, noting quality, quantity, or intensity and
8.6 Once the operating temperature has been established by duration of flaming or smoking, or both, and change of state.
thermocouple, T2, monitor and record the temperature on
thermocouple T1 during the test. 8.9 Note and record the time of occurrence of any flaming
and the duration of such flaming in seconds.
8.7 Test Procedure—As rapidly as possible, insert the test NOTE 4—Flaming is sometimes difficult to identify. Some specimens
specimen into the furnace with thermocouple T3 inserted from exhibit only flame as a steady blue-colored luminous gas zone. Do not
the top of the test specimen to its geometric center and ignore this and note it under “observations during test” in the test report.
thermocouple T4 attached to the side surface of the test 8.10 Weigh each test specimen before and after testing and
specimen. record the weight, in g, before and after the test for each test
8.7.1 Close the top cover to the 6.4-cm2 (1-in.2) opening specimen.
immediately after insertion of the test specimen. Readings for
thermocouples T3 and T4 shall be made at intervals (Note 3) not 8.11 Record the temperatures (initial, maximum and final),
to exceed 10 s during the first 5 min, and as often as necessary in °C, as measured by the appropriate thermocouples.
afterwards to produce a smooth curve. Do not change the
regulation of the current through the heating coils and the air 9. Calculation for Option A
flow during the test. 9.1 The calculations for Option A shall be conducted in
NOTE 3—A continuous read-out recording is preferred since it is accordance with 9.2 through 9.3.
possible for the maximum temperature to occur between the 10-s
intervals. 9.2 Calculate and record the weight loss for each of the test
specimens, expressed as a percentage of the initial weight of
8.7.2 Continue the test until the temperatures at thermo- the test specimen, to the nearest 1 %.
couples T3 and T4 have reached maxima, or until it is evident
that the specimen does not pass this test. 9.3 Calculate and record the temperature rise, in °C, for
8.7.3 After 30 min of testing have elapsed, or at any time each of the test specimens.
subsequent to that, testing shall be discontinued if, over the 9.3.1 Calculate the temperature rise as the difference be-
previous 10 minutes, the temperature measured at the center tween the maximum temperature and the initial temperature, as
thermocouple T3 has risen by no more than 1°C in any one measured by thermocouple, T3.

4
 E136 − 19a
10. Apparatus for Option B 15.2 If the weight loss of the test specimen is 50 % or less,
10.1 The apparatus used for Option B shall be in accordance the material passes the test when the criteria in 15.2.1 and in
with Section 6 of Test Method E2652. 15.2.2 are met:
15.2.1 The recorded temperatures of the surface and interior
10.2 When the apparatus of Test Method E2652 is used to thermocouples do not at anytime during the test rise more than
assess the behavior of building materials in accordance with 30°C (54°F) above the stabilized furnace temperature mea-
Test Method E136, measurements shall be made using both the sured at T2 prior to the test.
test specimen center thermocouple specified in 6.4.5.1 of Test 15.2.2 There is no flaming from the test specimen after the
Method E2652 and the test specimen surface thermocouple first 30 s.
specified in 6.4.5.2 of Test Method E2652. The values shall be
reported as required in Section 15 of Test Method E136 (see 15.3 If the weight loss of the specimen exceeds 50 %, the
also Appendix X1.8). material passes the test when the criteria in 15.3.1 and in 15.3.2
are met:
11. Test Specimens for Option B 15.3.1 The recorded temperature of the surface and interior
11.1 The test specimens used for Option B shall be in thermocouples do not, at any time during the test, rise above
accordance with Section 7 of Test Method E2652. the stabilized furnace temperature measured at T2 prior to the
test.
12. Test Setup and Calibration for Option B 15.3.2 No flaming from the test specimen is observed at any
12.1 The test specimens for Option B shall be in accordance time during the test.
with Section 8 of Test Method E2652. 15.4 Report the option that was used.
13. Test Procedure for Option B 16. Precision and Bias
13.1 The test procedure for Option B shall be in accordance 16.1 No information is presented about the precision and
with Section 9 of Test Method E2652. bias of this test method for measuring combustion character-
14. Calculations for Option B istics since the test results are nonquantitative and are reported
as pass or fail. (See X1.6.)
14.1 The calculations for Option B shall be in accordance
with Section 10 of E2652. 16.2 There have been attempts to determine precision and
bias for some of the numerical results for this test method but
15. Report the results have not been made public.
15.1 Report the material as passing the test if at least three
of the four test specimens tested meet the individual test 17. Keywords
specimen criteria detailed in 15.2 or 15.3. The three test 17.1 building materials; combustion; heated tube; limited
specimens do not need to meet the same individual test combustion; Setchkin furnace; tube furnace; vertical tube
specimen criteria. furnace

APPENDIX

(Nonmandatory Information)

X1. COMMENTARY

X1.1 Introduction Fire Underwriters (NBFU): Incombustible materials or con-

X1.1.1 The difference in fire risk between a combustible struction are those that “will not ignite or burn when subjected
building material and a noncombustible (or incombustible) one to fire.” In 1943 the same code redefined incombustible
is generally obvious. However, some materials may contain construction as “assemblies which do not involve materials of
only a limited amount of combustible content and may not such kind or quantity or so contained as to burn during
contribute appreciably to an ambient fire. The term exposure in a test fire or continue flaming or ignite after the
noncombustible, while in recognized use as indicating a furnace is shut off.”
material that will not ignite or burn, is indefinite in its X1.2.2 About this same time Committee C05 (now E05)
application unless referenced to a well defined testing proce- and the New York City Building Code suggested adding a
dure. reference of 649°C (1200°F) as the fire exposure temperature.
By 1949 the term incombustible was changed to noncombus-
X1.2 Definition tible in the National Building Code without definition. The first
X1.2.1 Most dictionaries have defined noncombustible in edition of the BOCA Basic Building Code (1950) defined a
simple terms, such as that used in the 1920 edition of the noncombustible material as “any material which will neither
National Building Code promulgated by the National Board of ignite or actively support combustion in air at a temperature of

5
 E136 − 19a
649°C [1200°F] during an exposure of five minutes in a vented conditions anticipated, will not ignite, burn, support
tube or vented crucible furnace.” combustion, or release flammable vapors, when subjected to
X1.2.3 The 1955 edition of the NBFU National Building fire or heat.
Code established a definition for noncombustible material (1)4 X1.2.6 To avoid misinterpretation in the use of the term
that was subsequently adopted by other model codes, the Life noncombustible, Committee E05 has decided to limit the use of
Safety Code (2), and most local codes. The adopted definition this term, and it was eliminated from the title and text of Test
was as follows: Method E136 in 1979. The current title provides a more
Noncombustible as applied to a building construction mate- specific description of the restricted nature of the test method.
rial means a material that, in the form in which it is used, falls
in one of the following groups (a) through (c). It does not apply X1.3 Origin and Early History of Test Method E136
to surface finish materials nor to the determination of whether X1.3.1 In 1912 R. E. Prince developed a furnace apparatus
a material is noncombustible from the standpoint of clearances to study the ignitability of various wood species and investigate
to heating appliances, flues or other sources of high tempera- the effect of fire-retardant chemical treatments on their ignition
ture. No material shall be classed as noncombustible which is characteristics (3, 4). This apparatus is shown in Fig. X1.1; it
subject to increase in combustibility or flame spread rating was called an “inflammability” apparatus and was originally
beyond the limits herein established, through the effects of age, described as the “Inflammability Apparatus No. 1.” It consisted
moisture or other atmospheric condition. Flame spread rating essentially of a quartz cylinder 76 mm [3 in.] in diameter and
as used herein refers to ratings obtained in accordance with 254 mm [10 in.] long, which was wound with a high electrical
Test Method E84. resistance nichrome ribbon. The cylinder was heavily insulated
a) Materials no part of which will ignite and burn when with asbestos. A lower chamber of about 89 mm (3.5 in.) in
subjected to fire. Any material that liberates flammable gas diameter and 203 mm (8 in.) deep formed a continuation of the
when heated to a temperature of 750°C (1382°F), for 5 min upper chamber. A natural draft was used. No attempt was made
shall not be considered noncombustible within the meaning of to control the temperature or humidity of the air passing
this paragraph. through the apparatus. The test temperature was 200°C
b) Materials having a structural base of noncombustible (392°F). The 32 by 32 by 102-mm (11⁄4 by 11⁄4 by 4-in.)
material, as defined in (a), with a surfacing not over 1⁄8-in. thick specimen was first weighted and then lowered in the hot quartz
that has a flame spread rating not higher than 50. cylinder where it remained until it ignited or for 40 min.
c) Materials, other than as described in (a) or (b), having a Ignition time, if it occurred, was recorded and the specimen
surface flame spread rating not higher than 25 without evidence was then moved into the lower cooler chamber and allowed to
of continued progressive combustion and of such composition burn for not more than 3 min. Loss of weight was then
that surfaces that would be exposed by cutting through the determined. A property defined as “intensity of burning” was
material in any way would not have a flame spread rating also measured.
higher than 25 without evidence of continued progressive
combustion. X1.3.2 An apparatus quite similar to the Prince-FPL appa-
ratus was later adopted, in 1932, as one of the parts of British
X1.2.4 In adopting this definition, NBFU stated that it was Standard 476. In a revision of that part of BS 476 in 1953 (BS
based on a determination of which materials “could be properly 476-4), the test was renamed, and the furnace was preheated
classed as noncombustible and then fixing the qualifying and maintained at 750°C (1382°F) prior to introduction of the
conditions in the definition to include these materials.” The specimen. This test specified that a material shall be considered
definition was considered to apply to materials used for the combustible if, during the 15-min test period, any one of six
walls, roofs, or other structural parts of buildings, but not to specimens was observed to flame, to produce vapors that were
surface finish materials and not to the determination of whether ignited by a pilot flame, or to cause the temperature of the
a material is noncombustible from the standpoint of clearances furnace to increase 50°C or more above 750°C ([1382°F). In a
to heating appliances, flues, or other sources of high tempera- report dated April 11, 1945, Dr. S. H. Ingberg suggested to
ture. Committee C05 (now E05) a method of test quite similar to the
X1.2.5 After Test Method E136 was promulgated, (initially British test. The apparatus, which is shown in Fig. X1.2, was
as a tentative in 1958, then as a full standard in 1965), many called an apparatus for incombustibility tests. A paper describ-
building codes replaced either part (a) of the NBFU definition ing the test was published in the ASTM proceedings (5, 6). The
or the entire definition with the specification that materials method differed from the British test by having the insulation
shall have been successfully tested in accordance with Test enclosure round instead of square and employed a constant
Method E136. In 1973, the American Insurance Association temperature of 750°C (1382°F) instead of a graduated tem-
(successor to NBFU) introduced a definition of a limited- perature. Specimen size was 50 by 38 mm [2 by 11⁄2 in.] by T
combustible material and redefined a noncombustible material where T equals the normal thickness or a maximum of 38 mm
as one that, in the form in which it is used and under the (11⁄2 in.).
X1.3.3 A variation of the 1945 proposed apparatus and a
method for determining the ignition temperature of plastics
4
The boldface numbers in parentheses refer to the list of references appended to under well controlled conditions was reported by N. P. Setch-
this method. kin in December 1949 (7). This apparatus is shown in Fig.

6
 E136 − 19a

FIG. X1.1 Inflammability Apparatus No. 1

X1.3. This test was subsequently adopted by Committee D20 X1.4. Committee E05 voted for retention of the standard
as Test Method D1929 in 1962, as a test method for determin- following its October 1963 meeting and at the same meeting
ing ignition temperature of plastics, and also by the ISO voted to advance Test Method E136 to a full standard that was
Technical Committee TC61 on Plastics as ISO 871, in 1980. published in 1965, with the title of “Standard Test Method for
Major changes included elimination of the lower chamber, the Determining Noncombustibility of Elementary Materials.” A
provision of two concentric refractory cylinders and a con- number of changes have been incorporated in revisions of the
trolled air flow directed between the cylinders, and the location apparatus and other provisions of this test method and some of
of thermocouples. them are described in other appendix sections.
X1.3.4 At the request of Subcommittee V (Nomenclature
and Definitions) of Committee E05, tests on 47 specimens of X1.4 Other Test Methods
solid materials were made in 1952 at the National Bureau of X1.4.1 At the request of the U.S. Coast Guard (June 3,
Standards (NBS; later renamed as National Institute of Stan- 1970), a test program at the NBS was coordinated by a task
dards and Technology (NIST)), the National Research Council subgroup of what was then a Subcommittee E05.05 to evaluate
of Canada, The Ohio State University, Southwest Research two principal tests used to determine combustibility: Test
Institute, and Owens-Corning Laboratories for the purpose of Method E136 and ISO R 1182(12). A modification of ISO 1182
evaluating a technique for determining the combustibility was adopted in 1973 by the Intergovernmental Maritime
classifications of solid materials (8, 9). Professor Shank, at The Consultative Organization (IMCO), an agency of the United
Ohio State University, continued work on the test method. Nations, for qualifying marine materials as noncombustible.
Through his efforts publication of a revised draft of the This test was designated Resolution A270 (VIII) and incorpo-
proposed test in the ASTM Bulletin was authorized at the rated changes in equipment details plus requirements for
February 8, 1957, meeting of Committee E05. Publication was approval as noncombustible materials; in the test method, the
for information purposes and comment (10). average duration of flaming was limited to 10 s. This test
X1.3.5 It was reported at the February 12, 1958, meeting of method was adopted in 1976 as the U.S. Coast Guard test for
Committee E05 that no comments or criticisms had been approval of noncombustible materials for merchant vessels.
received on the test method; a motion to publish it as a tentative X1.4.2 The test equipment in ISO R 1182 consists of a
test method was carried (11). The apparatus, described in 1958 refractory tube furnace insulated and surrounded by a heating
as the Tentative Standard Method of Test for Defining Non- coil. A cone-shaped airflow stabilizer is attached to the base of
combustibility of Building Materials was as shown in Fig. the furnace and a draft shield to its top. The testing is

7
 E136 − 19a

NOTE 1—

Legend:
Th 1—Thermocouple on outer wall
Th 2—Thermocouple in air stream
Th 3—Thermocouple in or on the specimen

FIG. X1.2 Ingberg Apparatus, called Apparatus for Incombustibil-

ity Tests FIG. X1.3 Setchkin Apparatus for Determining Ignition Tempera-
ture for Solids

performed in an open, vertically positioned, cylindrical fur- X1.4.5 The U.S. Coast Guard issued, in 1997, a Guide for
nace. The furnace is preheated to 750 °C before the test Structural Fire Protection as part of its Navigation and Vessel
specimen is introduced. During the test, temperatures in the Inspection Circular 9-97 (NVIC 9-97). This document was
furnace and at the specimen are measured. The duration of updated by a change (CH-1) on September 28, 2010, which
sustained flaming is also observed. The specimens are weighed became effective October 1, 2010. The U.S. Coast Guard stated
before and after the test, and the mass loss is assessed. One key that it does not intend to publish an amendment to the NVIC
difference between this test equipment and the original test beyond that notice.
equipment in Test Method E136 is that the latter does not X1.4.5.1 In NVIC 9-97 CH-1, the U.S. Coast Guard ad-
include a cone-shaped airflow stabilizer. opted the 1990 edition of ISO 1182 for assessment of noncom-
bustibility. NVIC 9-97 states that the temperature rise limits are
X1.4.3 ISO R 1182-1970 was superseded by ISO 1182-1979 determined by calculating the difference between the maxi-
using the apparatus shown in Fig. X1.5. The 1979 version mum furnace or surface temperature recorded during the test
contained modifications in the test method and equipment and the final furnace or surface temperatures, without taking
details. Furthermore, in that edition materials were no longer into account the initial furnace stabilization temperature. It
classified as noncombustible; instead, the following (average) specifies further that the timing device used to determine the
test results were reported: (1) maximum readings of the duration of flaming is to be started immediately following
furnace, surface, and center thermocouples; (2) duration of insertion of the specimen into the furnace. If the specimen
sustained flaming; and (3) mass loss. The annex in that edition exhibits open flaming before or during insertion, the test is
of ISO 1182 provided “suggested criteria for evaluation: not considered a failure irrespective of the material’s performance
more than 50 °C rise; not more than 20 s flaming; and not more after the timer has been started. NVIC 9-97 adopted the
than 50 % mass loss.” following noncombustibility acceptance criteria:
X1.4.4 The 1979 edition of ISO 1182 was superseded by (1) The average furnace temperature must not rise more
editions issued by ISO in 1990, 2002, and 2010, which than 30 °C;
involved a variety of changes. The 2010 edition of ISO 1182 (2) The specimen average surface temperature must not
contains no acceptance or suggested evaluation criteria. rise more than 30 °C;

8
 E136 − 19a

FIG. X1.4 Cross Section of Furnace Assembly

(3) The average duration of flaming must not exceed 10 s; X1.5.1.1 The need to measure and to limit the duration of
and flaming and the rise in temperature arose since a brief period of
(4) The average specimen weight loss must not exceed 50 flaming and a small amount of self heating were not considered
%. serious limitations to the use of building materials which would
otherwise be acceptable. Based on a series of tests on a wide
X1.5 Rationale for Test Method E136 Criteria variety of materials (9), a 30-s flame duration and a 30°C
X1.5.1 The choice of the 750°C (1382°F) furnace tempera- (54°F) rise were proposed as two criteria that could help to
ture derives basically from the BS 476 temperature limit. To distinguish between clearly combustible and clearly noncom-
some extent, it also represents the upper limit of temperatures bustible materials. The results of these tests indicated that the
quoted in early code definitions of noncombustible materials. It proposed levels would limit the combustible portion of non-
is a temperature that is representative of levels that are known combustible materials to a maximum of 3 %. It was further
to exist during building fires, although temperatures from 1000 suggested that the fire hazard characteristics of materials of
to 1200°C (1800 to 2200°F) are attained in intense fires. It is uncertain classification should be determined in large-scale
also used for determining the ash content of coal (Test Method tests.
D3174) although loss on ignition tests are commonly con- X1.5.2 The need to test at least four identical specimens was
ducted at 900 to 1000°C (1600 to 1800°F). For many building acknowledged in the initial 1957 proposal that specified that
materials, complete burning of the combustible fraction will the results of tests should be averaged (10). In 1958 (or 1959),
occur as readily at 750°C (1382°F) as at 900 to 1000°C (1600 the test method was written to require that the criteria apply to
to 1800°F). “three or more of the four specimens tested,” possibly to

9
 E136 − 19a

FIG. X1.5 ISO 1182-1979 Test Apparatus – General arrangement

recognize the variable nature of the measurement and the fact X1.5.4 It appears that the scope limitations to elementary
that there were difficulties in observing the presence and materials (through the 1973 edition) and the exclusion of
duration of flaming. laminated and coated materials reflected the uncertainties
X1.5.3 The 50 % weight loss limitation (8.2.3) is provided associated with more complex materials and with products that
to preclude the possibility that combustion of low density could not be tested in a realistic configuration.
materials will occur so rapidly that the recorded temperature
rise and the measured flaming duration will be less than the X1.6 Precision, Bias, and Sensitivity
prescribed limits. The choice of 50 % was considered desirable X1.6.1 This test method does not contain a numeric preci-
for materials that contain appreciable quantities of combined sion and bias statement because the reported results are
water (or gaseous components). recorded as pass or fail.

10
 E136 − 19a
X1.6.2 There have been attempts to determine precision and X1.7.2 A change that had generated controversy is the
bias for this method. Two series of interlaboratory tests have elimination of the previous restriction to elementary materials
been conducted in accordance with previous versions of this and the retention of the exclusion of laminated and coated
test method. In 1947, twelve years prior to the initial adoption materials. A 2018 ballot proposed reinstating the allowance to
of Test Method E136, a total of 47 solid materials were test laminated and coated materials but it received insufficient
provided for testing by seven laboratories, but no summary support.
report or conclusions on interlaboratory reproducibility appear X1.7.2.1 The major changes from E136 – 73 to E136 – 79
to have been developed. were (a) change in title; (b) removal of elementary from the
X1.6.3 In 1963, several laboratories participated in a limited scope; (c) addition of Significance and Use section; and (d)
round robin involving 13 materials and two test methods, replacement of the Interpretation of Results section containing
E136 – 73 and ISO R 1182. Results from three laboratories that the phrase “. . . shall be reported as noncombustible if . . .” with
provided data for Test Method E136 were compared in terms of a Report section containing the phrase “Report the material as
the surface temperature rise and in terms of the classification of passing the test if . . .” (13).
combustible or noncombustible (12). The variation in peak X1.7.3 During the December 1979 meeting of Committee
surface temperature rise typically ranged from 15 to 20°C (27 E05, a question was raised about the length of the ceramic
to 36°F) for temperature rises near the limiting value, for tubes in the Test Method E136 furnace specified to be 254 mm
example, 30 6 20°C (54 6 36°F) rise. In terms of (10 in.) long (outside cover 273 mm (103⁄4 in.)). A survey was
classification, the three laboratories agreed on a noncombus- made of Committee E05 members in January 1980 concerning
tible classification for four materials and on a combustible experience with and impact of size of tube on test results. A
classification for eight materials (although not necessarily by successful ballot to revise the size of the refractory tubes was
the same criteria). One material was classified combustible by accepted at the December 1980 meeting of the committee. The
one laboratory and noncombustible by two laboratories. revision is as currently stated in 6.1.1.
However, agreement would probably have been attained if the X1.7.4 In 1980 a proposal was made to substitute the
tests had not been terminated prematurely. No known sensitiv- furnace employed in ISO 1182 for the furnace used in Test
ity studies have been conducted on Test Method E136, al- Method E136 but to retain all other details of the test method.
though one laboratory did perform a sensitivity study in 1973 This proposal was not accepted.
on ISO R 1182 and concluded that the peak surface tempera-
ture rise was not sensitive to the prescribed change in furnace X1.7.5 Additional information can provide comparisons of
temperature level 730°C versus 750°C or in specimen location Test Method E136, ISO 1182, and the IMCO (modified ISO)
(mid-height of furnace versus 20 mm (3⁄4 in.) below mid- test methods (14-20). Test Method E136 is under the jurisdic-
height). tion of Subcommittee E05.23 of Committee E05 on Fire
Standards.
X1.7 Activity at Committee E05 after 1970 X1.7.6 In 1992, Subcommittee E05.23 approved an addition
X1.7.1 In addition to the inclusion of the weight loss to this test method in order to provide a value for the volume
limitation, the 1973 edition of the test method also included the air flow rate through the test furnace, in addition to the linear
response characteristics of the measuring thermocouples T3 air flow rate that had been listed since the creation of the
and T4 in terms of a specified time constant. A mandatory standard. The volume flow, which is derived from the linear
caveat established by the ASTM Board of Directors for flow, is the value actually used to monitor the air flow rate
fire-test-response standards was added editorially in July 1974, during testing. The value for volume flow rate in the 1993 and
and later amended to be identical to that in Section F2.2.2.1 of 1994 versions of this test method was incorrect. This value
the ASTM Form and Style Manual. More recently, the Form assumed that the linear flow rate (3.0 m/min) was at room
and Style Manual required a second caveat for fire test temperature (approximately 21 °C), rather than at the elevated
methods, contained in Section F2.2.2.6. furnace temperature 750 °C. The difference in the two calcu-
X1.7.1.1 Following extensive debate regarding the elimina- lations for the volume flow rate is approximately a factor of
tion of pass-fail criteria, the criteria remained. The rationale for three (correct calculation, 0.00267 m3 /min; incorrect
eliminating the pass-fail feature of the test was that the calculation, 0.00927 m3/min). It was not the intent of the task
selection of limit values was arbitrary and that these should group or subcommittee to change the test method, which was
properly be set by the building officials using the test method. based on linear air flow rate.
While physical, thermal, and flammability properties are com- X1.7.7 In 2007 another proposal suggested the substitution
monly included in specifications, such endpoints are not of the test apparatus for the ISO 1182 apparatus and it was
normally included in ASTM fire test methods, except as a again not accepted.
means for separating materials into classes or types. However X1.7.7.1 In 2008 agreement was reached between ASTM
it was also held that the inclusion of a single set of commonly and ISO that ASTM would develop a new fire test standard
accepted limit values would avoid a possible proliferation of based on the ISO 1182 test apparatus. That resulted in the
endpoints in different codes and standards. In fact, the pass-fail development of Test Method E2652.
criteria in Section 15 are typically used to determine that a X1.7.7.2 In 2009 a first edition of Test Method E2652 was
material is noncombustible in accordance with this test published, and in 2011, Test Method E136 was revised to
method. contain an Option A (which is the traditional test apparatus)

11
 E136 − 19a
and an Option B (which is the Test Method E2652 test Test Method E136. The use of these thermocouples is manda-
apparatus). The pass-fail criteria to be used for both options is tory when testing with Test Method E2652 and is intended to
the same and it is the one previously contained in Test Method comply with Test Method E136 but not when testing is
E136. intended to comply with ISO 1182.
X1.7.7.3 In 2012 an annex was added to Test Method E2652 X1.8.2 The apparatus used for Option B of Test Method
describing thermocouples at the test specimen center and test E136 is the apparatus of Test Method E2652.
specimen surface (see Appendix X1.8). Since then, when Test
X1.8.3 Therefore, Section 10.2 of Test Method E136 and
Method E2652 is conducted to compare with the pass-fail
Section 6.4.8 of Test Method E2652 explain that when the
criteria in Test Method E136, those two thermocouples are
apparatus of Test Method E2652 is used to assess the behavior
required to be used.
of building materials in accordance with Test Method E136,
measurements need to be made using both of the optional
X1.8 Optional Thermocouples in Test Method E2652
thermocouples specified in Sections 6.4.6 (test specimen center
X1.8.1 Earlier editions of Test Method E2652 did not thermocouple) and 6.4.7 (test specimen surface thermocouple)
require the use of the test specimen center thermocouple or of of Test Method E2652. The sections also explain that the
the test specimen surface thermocouple. However, measure- values of these measurements must be reported as required in
ments using these thermocouples are required in Section 15 of Section 15 of Test Method E136.

REFERENCES

(1) “Definition of Noncombustible Building Construction Material,” (10) Proposed Method of Test for Defining Noncombustibility of Build-
Special Interest Bulletin No. 294, revised August 1967, American ing Materials “,” ASTM Bulletin, February 1957. pp. 33–34.
Insurance Assn., New York, NY. (11) Yuill, C. H., “Fire Terms and Fire Tests,” Materials Research and
(2) “Life Safety Code,” NFPA 101, National Fire Protection Assn., Standards, Vol 10, No. 10. American Society for Testing and
Quincy, MA 1976. Materials, 1970, pp. 24–26.
(3) Eickner, H. W., “Fire Research at the U.S. Forest Products (12) Gross, D., Lindauer, R. A., and Willard, R., “Evaluation of Two Test
Laboratory,” Approved Technical Article, Fire Research Abs. and Methods for Noncombustibility: ASTM E136 and ISO R1182,”
Rev., National Academy of Science and National Research Council, Unpublished NBS Report, 1973.
Vol 6, No. 1, 1964. Washington, D.C. (13) Explanation accompanying ballot on ASTM Test Method E136, Item
(4) Prince, R. E., “Tests on the Inflammability of Untreated Wood and 4, January 1978.
Wood Treated with Fire-Retarding Compounds,” NFPA Proceedings, (14) Loftus, J. J., “Noncombustibility of Mineral Wood and Glass Fiber
1915, pp. 108–112. Insulation Materials,” NBS Report 9988, Feb. 3, 1969.
(5) Setchkin, N. P. and Ingberg, S. H., “Test Criterion for an Incombus- (15) Benjamin, I. A., “ISO Noncombustibility Furnace,” NBS Report
tible Material,” Proceedings of the American Society for Testing 10330, Aug. 28, 1970.
Materials, Philadelphia, PA, Vol 45, 1945. (16) Gross, D. and Benjamin, I. A., “Evaluation of ISO Furnace Test for
(6) Ingberg, S. H., Notes on E136 – 59 T and Requirements for Noncombustibility,” Unpublished NBS Report, March 15, 1971.
Incombustibility, 11 pp. Minutes of ASTM Committee E-5, October (17) McDaniel, D. E., “Noncombustibility: A Marine View,” Ignition,
13, 1964 and January 15, 1965 (copy at ASTM Headquarters). Heat Release, and Noncombustibility of Materials, ASTM STP 502,
(7) Setchkin, N. P., “A Method and Apparatus for Determining the Am. Soc. Testing Mats., 1971.
Ignition Characteristics of Plastics,” Research Paper RP 2052, Jour- (18) Herpol, G. A., “Noncombustibility—Its Definition, Measurement,
nal of Research, National Bureau of Standards Vol 43, December and Applications,” Ignition, Heat Release, and Noncombustibility of
1949, pp. 591–608. Materials, STP 502, Am. Soc. Testing Mats., 1971.
(8) Sumi, K., Comparison of Combustibility Test Procedures, Report No. (19) Loftus, J. J. and Robertson, A. F., Experiments with A Proposed Test
43, Division of Building Research, National Research Council of Procedure for Noncombustible Materials, NBS Report 9529, May 4,
Canada, Ottawa, Ont., July 1955. 1967.
(9) Setchkin, N. P., Combustibility Tests of 47 ASTM Material Samples (20) Report of Test on Five Asbestos Type Insulation Boards for United
National Bureau of Standards (NBS) Project 1002-43-1029, Report States Coast Guard—Report No. TG10210-2183: FR 3720. U.S.
No. 1454, Feb. 6, 1952, Washington, D.C. National Bureau of Standards.

12
 E136 − 19a
SUMMARY OF CHANGES

Committee E05 has identified the location of selected changes to this standard since the last issue (2019) that
may impact the use of this standard. (Approved Dec. 15, 2019.)

(1) Appendix Sections X1.3, X1.4, and X1.7 were updated.

Committee E05 has identified the location of selected changes to this standard since the last issue (2016a) that
may impact the use of this standard. (Approved Feb.1, 2019.)

(1) The title was revised. (3) Paragraph 5.1 was added.
(2) Paragraph 1.1 was revised.

ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentioned
in this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the risk
of infringement of such rights, are entirely their own responsibility.

This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years and
if not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standards
and should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of the
responsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you should
make your views known to the ASTM Committee on Standards, at the address shown below.

This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,
United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the above
address or at 610-832-9585 (phone), 610-832-9555 (fax), or service@astm.org (e-mail); or through the ASTM website
(www.astm.org). Permission rights to photocopy the standard may also be secured from the Copyright Clearance Center, 222
Rosewood Drive, Danvers, MA 01923, Tel: (978) 646-2600; http://www.copyright.com/

13