ASTM G74-13
(Test Method)Standard Test Method for Ignition Sensitivity of Nonmetallic Materials and Components by Gaseous Fluid Impact
Standard Test Method for Ignition Sensitivity of Nonmetallic Materials and Components by Gaseous Fluid Impact
SIGNIFICANCE AND USE
4.1 This test standard describes how to evaluate the relative sensitivity of materials and components to dynamic pressure impacts by various gaseous fluid media (can include gas mixtures).
4.2 Changes or variations in test specimen configurations, thickness, preparation, and cleanliness can cause a significant change in their impact ignition sensitivity/reaction. For material tests, the test specimen configuration shall be specified on the test report.
4.3 Changes or variation in the test system configuration from that specified herein may cause a significant change in the severity produced by a dynamic pressure surge of the gaseous media.
4.4 A reaction is indicated by an abrupt increase in test specimen temperature, by obvious changes in odor, color, or material appearance, or a combination thereof, as observed during post-test examinations. Odor alone is not considered positive evidence that a reaction has occurred. When an increase in test specimen temperature is observed, a test specimen reaction must be confirmed by visual inspection. To aid with visual inspection, magnification less than 10× can be used.
4.5 When testing components, the test article must be disassembled and the nonmetallic materials examined for evidence of ignition after completion of the specified pressure surge cycles.
4.6 Ignition or precursors to ignition for any test sample shall be considered a failure and are indicated by burning, material loss, scorching, or melting of a test material detected through direct visual means. Ignition is often indicated by consumption of the non-metallic material under test, whether as an individual material or within a component. Partial ignition can also occur, as shown in Fig. 3a, b, and c, and shall also be considered an ignition (failure) for the purpose of this test standard.
4.7 For material testing, the prescribed procedure is conducted on multiple samples until a statistically significant number of ignitions or no-ignitions, o...
SCOPE
1.1 This test method describes a method to determine the relative sensitivity of nonmetallic materials (including plastics, elastomers, coatings, etc.) and components (including valves, regulators flexible hoses, etc.) to dynamic pressure impacts by gases such as oxygen, air, or blends of gases containing oxygen.
1.2 This test method describes the test apparatus and test procedures employed in the evaluation of materials and components for use in gases under dynamic pressure operating conditions up to gauge pressures of 69 MPa and at elevated temperatures.
1.3 This test method is primarily a test method for ranking of materials and qualifying components for use in gaseous oxygen. The material test method is not necessarily valid for determination of the sensitivity of the materials in an “as-used” configuration since the material sensitivity can be altered because of changes in material configuration, usage, and service conditions/interactions. However, the component testing method outlined herein can be valid for determination of the sensitivity of components under service conditions. The current provisions of this method were based on the testing of components having an inlet diameter (ID bore) less than or equal to 14 mm (see Note 1).
1.4 A 5 mm Gaseous Fluid Impact Sensitivity (GFIS) test system and a 14 mm GFIS test system are described in this standard. The 5 mm GFIS system is utilized for materials and components that are directly attached to a high-pressure source and have minimal volume between the material/component and the pressure source. The 14 mm GFIS system is utilized for materials and components that are attached to a high pressure source through a manifold or other higher volume or larger sized connection. Other sizes than these may be utilized but no attempt has been made to characterize the thermal profiles of other volumes and geometries (see Note 1).Note 1—The energy delivered by this test ...
General Information
Buy Standard
Standards Content (Sample)
NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: G74 − 13
Standard Test Method for
Ignition Sensitivity of Nonmetallic Materials and
1
Components by Gaseous Fluid Impact
ThisstandardisissuedunderthefixeddesignationG74;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginal
adoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscript
epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope attempt has been made to characterize the thermal profiles of
other volumes and geometries (see Note 1).
1.1 This test method describes a method to determine the
NOTE 1—The energy delivered by this test method is dependent on the
relativesensitivityofnonmetallicmaterials(includingplastics,
gas volume being rapidly compressed at the inlet to the test specimen or
elastomers, coatings, etc.) and components (including valves,
testarticle.Thereforethegeometryoftheupstreamvolume(diameterand
regulators flexible hoses, etc.) to dynamic pressure impacts by
length) is crucial to the test and crucial to the application of the results to
actual service conditions. It is therefore recommended that caution be
gases such as oxygen, air, or blends of gases containing
exercised in applying the results of this testing to rapid pressurization of
oxygen.
volumes larger than those standardized by this test method. This energy
1.2 This test method describes the test apparatus and test
deliveredbythisstandardisbasedontherapidcompressionofthevolume
in eithera5mmIDby 1000 mm long impact tube or a 14 mm ID by 750
procedures employed in the evaluation of materials and com-
mm long impact tube. These two upstream volumes are specified in this
ponents for use in gases under dynamic pressure operating
standard based on historic application within the industry.
conditions up to gauge pressures of 69 MPa and at elevated
1.5 This test method can be utilized to provide batch-to-
temperatures.
batch comparison screening of materials when the data is
1.3 This test method is primarily a test method for ranking
analyzed according to the methods described herein. Accept-
of materials and qualifying components for use in gaseous
ability of any material by this test method may be based on its
oxygen. The material test method is not necessarily valid for
50% reaction pressure or its probability of ignition based on a
determinationofthesensitivityofthematerialsinan“as-used”
logistic regression analysis of the data (described herein).
configuration since the material sensitivity can be altered
1.6 Many ASTM, CGA, and ISO test standards require
because of changes in material configuration, usage, and
ignition testing of materials and components by gaseous fluid
service conditions/interactions. However, the component test-
impact, also referred to as adiabatic compression testing. This
ing method outlined herein can be valid for determination of
test method provides the test system requirements consistent
the sensitivity of components under service conditions. The
with the requirements of these other various standards. The
current provisions of this method were based on the testing of
pass/fail acceptance criteria may be provided within other
components having an inlet diameter (ID bore) less than or
standards and users should refer to those standards. Pass/fail
equal to 14 mm (see Note 1).
guidance is provided in this standard such as that noted in
1.4 A 5 mm Gaseous Fluid Impact Sensitivity (GFIS) test
section 4.6. This test method is designed to ensure that
system and a 14 mm GFIS test system are described in this
consistent gaseous fluid impact tests are conducted in different
standard. The 5 mm GFIS system is utilized for materials and
laboratories.
componentsthataredirectlyattachedtoahigh-pressuresource
1.7 The criteria used for the acceptance, retest, and
andhaveminimalvolumebetweenthematerial/componentand
rejection, or any combination thereof of materials and compo-
the pressure source. The 14 mm GFIS system is utilized for
nentsforanygivenapplicationshallbedeterminedbytheuser
materials and components that are attached to a high pressure
and are not fixed by this method. However, it is recommended
source through a manifold or other higher volume or larger
that at a minimum the 95% confidence interval be established
sizedconnection.Othersizesthanthesemaybeutilizedbutno
for all test results since ignition by this method is inherently
probabilistic and should be treated by appropriate statistical
1
This test method is under the jurisdiction of ASTM Committee G04 on
methods.
Compatibility and Sensitivity of Materials in Oxygen EnrichedAtmospheres and is
the direct responsibility of Subcommittee G04.01 on Test Methods.
1.8 The values stated in SI units are to be regarded as
Current edition approved May 1, 2013. Published October 2013. Originally
s
...
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: G74 − 08 G74 − 13
Standard Test Method for
Ignition Sensitivity of Materials to Nonmetallic Materials and
1
Components by Gaseous Fluid Impact
This standard is issued under the fixed designation G74; 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 describes a techniquemethod to determine the relative sensitivity of materials nonmetallic materials
(including plastics, elastomers, coatings, etc.) and components (including valves, regulators flexible hoses, etc.) to dynamic
pressure impacts by gases such as oxygen, air, or blends of gases containing oxygen.
1.2 This test method describes the test apparatus and test procedures that may be employed in the evaluation of materials and
components for use in gases under dynamic pressure operating conditions up to gagegauge pressures of 10 000 psi (69 MPa) at
ambient temperature.69 MPa and at elevated temperatures.
1.3 This test method is primarily a test method for ranking of materials. This materials and qualifying components for use in
gaseous oxygen. The material test method is not necessarily valid for determination of the sensitivity of the materials in an
“as-used” configuration since the material sensitivity maycan be altered because of changes in material configuration, usage, and
environment. Acceptability of any material may be based on its performance at a particular test pressure, or test pressure may be
varied to determine the reactionservice conditions/interactions. However, the component testing method outlined herein can be
valid for determination of the sensitivity of components under service conditions. The current provisions of this method were based
on the testing of components having an inlet diameter (ID bore) less than or equal to 14 mm (see Note 1threshold of a material,
as specified by the user.).
1.4 A 5 mm Gaseous Fluid Impact Sensitivity (GFIS) test system and a 14 mm GFIS test system are described in this standard.
The 5 mm GFIS system is utilized for materials and components that are directly attached to a high-pressure source and have
minimal volume between the material/component and the pressure source. The 14 mm GFIS system is utilized for materials and
components that are attached to a high pressure source through a manifold or other higher volume or larger sized connection. Other
sizes than these may be utilized but no attempt has been made to characterize the thermal profiles of other volumes and geometries
(see Note 1).
NOTE 1—The energy delivered by this test method is dependent on the gas volume being rapidly compressed at the inlet to the test specimen or test
article. Therefore the geometry of the upstream volume (diameter and length) is crucial to the test and crucial to the application of the results to actual
service conditions. It is therefore recommended that caution be exercised in applying the results of this testing to rapid pressurization of volumes larger
than those standardized by this test method. This energy delivered by this standard is based on the rapid compression of the volume in either a 5 mm
ID by 1000 mm long impact tube or a 14 mm ID by 750 mm long impact tube. These two upstream volumes are specified in this standard based on historic
application within the industry.
1.5 This test method can be utilized to provide batch-to-batch comparison screening of materials when the data is analyzed
according to the methods described herein. Acceptability of any material by this test method may be based on its 50 % reaction
pressure or its probability of ignition based on a logistic regression analysis of the data (described herein).
1.6 Many ASTM, CGA, and ISO test standards require ignition testing of materials and components by gaseous fluid impact,
also referred to as adiabatic compression testing. This test method provides the test system requirements consistent with the
requirements of these other various standards. The pass/fail acceptance criteria may be provided within other standards and users
should refer to those standards. Pass/fail guidance is provided in this standard such as that noted in section 4.6. This test method
is designed to ensure that consistent gaseous fluid impact tests are conducted in different laboratories.
1.7 The criteria used for the acceptance, retest, and rejecti
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.