ASTM D3874-20

Standard Test Method for Ignition of Materials by Hot Wire Sources

SIGNIFICANCE AND USE
5.1 During operation of electrical equipment, including wires, resistors, and other conductors, it is possible for overheating to occur, under certain conditions of operation or when malfunctions occur. When this happens, a possible result is ignition of the insulation material.  
5.2 This test method assesses the relative resistance of electrical insulating materials to ignition by the effect of hot wire sources.  
5.3 This test method determines the average time, in seconds, required for material specimens to ignite under the specified conditions of test.  
5.4 This method is suitable to characterize materials, subject to the appropriate limitations of an expected precision of ±15 %, to categorize materials.  
5.5 In this procedure the specimens are subjected to one or more specific sets of laboratory conditions. If different test conditions are substituted or the end-use conditions are changed, it is not always possible by or from this test to predict changes in the fire-test-response characteristics measured. Therefore, the results are valid only for the fire test exposure conditions described in this procedure.
SCOPE
1.1 This test method is intended to differentiate, in a preliminary fashion, among materials with respect to their resistance to ignition because of their proximity to electrically-heated wires and other heat sources.2  
1.2 This test method applies to molded or sheet materials available in thicknesses up to and including 13.0 mm (0.51 in.).  
1.3 This test method applies to materials that are rigid or flexible at normal room temperatures. It is important to minimize deformation during preparation, especially during the wire-wrapping step described in 10.1, by following the method outlined under Clause 10, Sample Preparation. Examples of deformation include bowing, in either a transverse or a longitudinal direction, twisting of the specimen, and indentation of the wire into the specimen during the wire-wrapping step, to a degree visible to the eye.  
1.4 The values stated in SI units are to be regarded as standard. The values given in parentheses after SI units are provided for information only and are not considered standard. (See SI10 for further details.)  
1.5 This test method measures and describes the response of materials, products, or assemblies to heat and flame under controlled conditions, but does not by itself incorporate all factors required for fire hazard or fire risk assessment of the materials, products, or assemblies under actual fire conditions.  
1.6 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 appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.7 Fire testing is inherently hazardous. Adequate safeguards for personnel and property shall be employed in conducting these tests.
Note 1: Although this test method and IEC TS 60695-2-20 (withdrawn) differ in approach and in detail, data obtained using either are technically equivalent.  
1.8 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.

General Information

• Status: Published
• Publication Date: 29-Feb-2020
• ICS: 13.220.40 - Ignitability and burning behaviour of materials and products
• ICS: 29.035.01 - Insulating materials in general
• Technical Committee: D09 - Electrical and Electronic Insulating Materials
• Drafting Committee: D09.17 - Fire and Thermal Properties

Relations

• Referred By: ASTM E3020-22 - Standard Practice for Ignition Sources
• Effective Date: 01-Mar-2020

Standards Content (Sample)

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: D3874 − 20
Standard Test Method for
1
Ignition of Materials by Hot Wire Sources
This standard is issued under the fixed designation D3874; 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.
NOTE 1—Although this test method and IEC TS 60695-2-20 (with-
1. Scope*
drawn) differ in approach and in detail, data obtained using either are
1.1 This test method is intended to differentiate, in a
technically equivalent.
preliminary fashion, among materials with respect to their
1.8 This international standard was developed in accor-
resistance to ignition because of their proximity to electrically-
dance with internationally recognized principles on standard-
2
heated wires and other heat sources.
ization established in the Decision on Principles for the
1.2 This test method applies to molded or sheet materials
Development of International Standards, Guides and Recom-
availableinthicknessesuptoandincluding13.0mm(0.51 in.). mendations issued by the World Trade Organization Technical
Barriers to Trade (TBT) Committee.
1.3 This test method applies to materials that are rigid or
flexible at normal room temperatures. It is important to
2. Referenced Documents
minimize deformation during preparation, especially during
3
2.1 ASTM Standards:
the wire-wrapping step described in 10.1, by following the
D1711 Terminology Relating to Electrical Insulation
method outlined under Clause 10, Sample Preparation. Ex-
D6194 Test Method for Glow-Wire Ignition of Materials
amplesofdeformationincludebowing,ineitheratransverseor
E176 Terminology of Fire Standards
a longitudinal direction, twisting of the specimen, and inden-
E3020 Practice for Ignition Sources
tation of the wire into the specimen during the wire-wrapping
IEEE/ASTM SI-10 American National Standard for Metric
step, to a degree visible to the eye.
Practice
1.4 The values stated in SI units are to be regarded as 4
2.2 IEC Standards:
standard. The values given in parentheses after SI units are
IEC TS 60695-2-20:2004 Fire Hazard Testing—Section 20:
provided for information only and are not considered standard.
Glowing/Hot-wire Based Test Methods, Hot-wire Coil
(See SI10 for further details.)
Ignitability Test on Materials (withdrawn)
1.5 Thistestmethodmeasuresanddescribestheresponseof
IEC 60695-4 Fire Hazard Testing—Part 4: Terminology
materials, products, or assemblies to heat and flame under
Concerning Fire Tests for Electrotechnical Products
5
controlled conditions, but does not by itself incorporate all
2.3 ISO Standard:
factors required for fire hazard or fire risk assessment of the
ISO 13943 Fire Safety—Vocabulary
materials, products, or assemblies under actual fire conditions.
3. Terminology
1.6 This standard does not purport to address all of the
3.1 Definitions:
safety concerns, if any, associated with its use. It is the
3.1.1 Use Terminology E176, ISO 13943, and IEC 60695-4
responsibility of the user of this standard to establish appro-
for definitions of terms used in this test method and associated
priate safety, health, and environmental practices and deter-
with fire issues. Where differences exist in definitions, those
mine the applicability of regulatory limitations prior to use.
contained in Terminology E176 shall be used. Use Terminol-
1.7 Fire testing is inherently hazardous. Adequate safe-
ogy D1711 for definitions of terms used in this test method and
guards for personnel and property shall be employed in
associated with electrical insulation materials.
conducting these tests.
3
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
1
This test method is under the jurisdiction of ASTM Committee D09 on contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
Electrical and Electronic Insulating Materials and is the direct responsibility of Standards volume information, refer to the standard’s Document Summary page on
Subcommittee D09.17 on Fire and Thermal Properties. the ASTM website.
4
Current edition approved March 1, 2020. Published March 2020. Originally Available from International Electrotechnical Commission (IEC), 3, rue de
approved in 1988. Last previous edition approved in 2018 as D3874 – 18. DOI: Varembé, 1st floor, P.O. Box 131, CH-1211, Geneva 20, Switzerland, https://
10.1520/D3874-20. www.iec.ch.
2 5
Mathes, K. N., “Surface Failure Measurements,” Engineering Dielectrics, Available from International Organization for Standardization (ISO), ISO
Vol II
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: D3874 − 18 D3874 − 20
Standard Test Method for
1
Ignition of Materials by Hot Wire Sources
This standard is issued under the fixed designation D3874; 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.
1. Scope*
1.1 This test method is intended to differentiate, in a preliminary fashion, among materials with respect to their resistance to
2
ignition because of their proximity to electrically-heated wires and other heat sources.
1.2 This test method applies to molded or sheet materials available in thicknesses ranging from 0.25 to 6.4 mm (0.010 to 0.25
in.).up to and including 13.0 mm (0.51 in.).
1.3 This test method applies to materials that are rigid or flexible at normal room temperatures. That is, it applies to materials
for which the specimen does not deform It is important to minimize deformation during preparation, especially during the
wire-wrapping step described in 10.1. , by following the method outlined under Clause 10, Sample Preparation. Examples of
deformation that render this test method inapplicable include:include bowing, in either a transverse or a longitudinal direction,
twisting of the specimen, and indentation of the wire into the specimen during the wire-wrapping step, to a degree visible to the
eye.
1.3.1 Bowing, in either a transverse or a longitudinal direction, or twisting of the specimen, during the wire-wrapping step, to
a degree visible to the eye.
1.3.2 Visible indentation of the wrapped wire into the specimen.
1.4 The values stated in SI units are to be regarded as the standard. The inch-pound units values given in parentheses are for
information only. after SI units are provided for information only and are not considered standard. (See SI10 for further details.)
1.5 This test method measures and describes the response orof materials, products, or assemblies to heat and flame under
controlled conditions, but does not by itself incorporate all factors required for fire hazard or fire risk assessment of the materials,
products, or assemblies under actual fire conditions.
1.6 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 appropriate safety, health, and environmental practices and determine the applicability of
regulatory limitations prior to use.
1.7 Fire testing is inherently hazardous. Adequate safeguards for personnel and property shall be employed in conducting these
tests.
NOTE 1—Although this test method and IEC TS 60695-2-20 (withdrawn),(withdrawn) differ in approach and in detail, data obtained using either are
technically equivalent.
1.8 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.
2. Referenced Documents
3
2.1 ASTM Standards:
D1711 Terminology Relating to Electrical Insulation
D6194 Test Method for Glow-Wire Ignition of Materials
E176 Terminology of Fire Standards
1
This test method is under the jurisdiction of ASTM Committee D09 on Electrical and Electronic Insulating Materials and is the direct responsibility of Subcommittee
D09.17 on Fire and Thermal Properties.
Current edition approved Nov. 1, 2018March 1, 2020. Published November 2018March 2020. Originally approved in 1988. Last previous edition approved in 20132018
as D3874 – 13.D3874 – 18. DOI: 10.1520/D3874-18. 10.1520/D3874-20.
2
K. N. Mathes, Chapter 4,Mathes, K. N., “Surface Failure Measurements”,Measurements,” Engineering Dielectrics, Vol. IIB, Vol IIB, Electrical Properties of Solid
Insulating Materials,Materials: Measurement Techniques, R. Bartnikas, Editor, ASTM STP 926, ASTM, Philadelphia, Chapter 4, ASTM International, 1987.
3
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
*A Summary of Changes section appears at the end of this standard
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...