ASTM E918-19

Standard Practice for Determining Limits of Flammability of Chemicals at Elevated Temperature and Pressure

SIGNIFICANCE AND USE
5.1 Knowledge of flammable limits at elevated temperatures and pressures is needed for safe and economical operation of some chemical processes. This information may be needed in order to start up a reactor without passing through a flammable range, to operate the reactor safely and economically, or to store or ship the product safely.  
5.2 Limits of flammability data obtained in relatively clean vessels must be carefully interpreted and may not always be applicable to industrial conditions. Surface effects due to carbon deposits and other materials can significantly affect limits of flammability, especially in the fuel-rich region. Refer to Bulletin 503 and Bulletin 627.
SCOPE
1.1 This practice covers the determination of the lower and upper concentration limits of flammability of combustible vapor-oxidant mixtures at temperatures up to 200°C and initial pressures up to as much as 1.38 MPa (200 psia). This practice is limited to mixtures which would have explosion pressures less than 13.79 MPa (2000 psia).  
1.2 This practice should be used to measure and describe the properties of materials, products, or assemblies in response to heat and flame under controlled laboratory conditions and should not be used to describe or appraise the fire hazard or fire risk of materials, products, or assemblies under actual fire conditions. However, results of this test may be used as elements of a fire risk assessment which takes into account all of the factors which are pertinent to an assessment of the fire hazard of a particular end use.  
1.3 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.  
1.4 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: 30-Nov-2019
• ICS: 13.220.40 - Ignitability and burning behaviour of materials and products
• ICS: 71.100.01 - Products of the chemical industry in general
• Technical Committee: E27 - Hazard Potential of Chemicals
• Drafting Committee: E27.04 - Flammability and Ignitability of Chemicals

Relations

• Refers: ASTM E2079-19 - Standard Test Methods for Limiting Oxygen (Oxidant) Concentration in Gases and Vapors
• Effective Date: 01-Jul-2019
• Referred By: ASTM E1445-08(2015) - Standard Terminology Relating to Hazard Potential of Chemicals
• Effective Date: 01-Dec-2019

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: E918 − 19
Standard Practice for
Determining Limits of Flammability of Chemicals at Elevated
1
Temperature and Pressure
This standard is issued under the fixed designation E918; 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 E2079 Test Methods for Limiting Oxygen (Oxidant) Con-
centration in Gases and Vapors
1.1 This practice covers the determination of the lower and
2.2 Other Documents:
upper concentration limits of flammability of combustible
Bulletin 503 Bureau of Mines, “Limits of Flammability of
vapor-oxidant mixtures at temperatures up to 200°C and initial
3
Gases and Vapors,” NTIS AD701575
pressures up to as much as 1.38 MPa (200 psia). This practice
Bulletin 627 Bureau of Mines, “Flammability Characteris-
is limited to mixtures which would have explosion pressures
3
tics of Combustible Gases andVapors,” NTISAD701576
less than 13.79 MPa (2000 psia).
1.2 This practice should be used to measure and describe
3. Terminology
the properties of materials, products, or assemblies in response
3.1 Definitions:
to heat and flame under controlled laboratory conditions and
3.1.1 lower limit of flammability or lower flammable limit
should not be used to describe or appraise the fire hazard or
(LFL), n—the minimum concentration of a combustible sub-
fire risk of materials, products, or assemblies under actual fire
stance that is capable of propagating a flame through a
conditions. However, results of this test may be used as
homogeneous mixture of the combustible and a gaseous
elements of a fire risk assessment which takes into account all
oxidizer under the specified conditions of test.
of the factors which are pertinent to an assessment of the fire
3.1.2 upper limit of flammability or upper flammable limit
hazard of a particular end use.
(UFL), n—the maximum concentration of a combustible sub-
1.3 This standard does not purport to address all of the
stance that is capable of propagating a flame through a
safety concerns, if any, associated with its use. It is the
homogeneous mixture of the combustible and a gaseous
responsibility of the user of this standard to establish appro-
oxidizer under the specified conditions of test.
priate safety, health, and environmental practices and deter-
mine the applicability of regulatory limitations prior to use. 3.2 Definitions of Terms Specific to This Standard:
3.2.1 propagation of flames, n—as used in this practice,a
1.4 This international standard was developed in accor-
dance with internationally recognized principles on standard- combustion reaction that produces at least a 7 % rise of the
initial absolute pressure:
ization established in the Decision on Principles for the
Development of International Standards, Guides and Recom-
P
2
^1.07
mendations issued by the World Trade Organization Technical
P
1
Barriers to Trade (TBT) Committee.
NOTE 1—This 7 % rise in pressure corresponds to 1 psia (0.007 MPa)
per atmosphere of initial pressure.
2. Referenced Documents
NOTE 2—The 7 % pressure criterion may not be appropriate for certain
fuelandoxidantmixtures.Thisisalsothecaseifthetestenclosurevolume
2
2.1 ASTM Standards:
is small, or when the ignition energy is substantially larger than 10 J. It is
E681 Test Method for Concentration Limits of Flammability
therefore a prudent practice to perform exploratory tests in the vicinity of
of Chemicals (Vapors and Gases) limit mixtures to evaluate the validity of the selected pressure rise
4
,5
criterion.
1
This practice is under the jurisdiction of ASTM Committee E27 on Hazard
3
Potential of Chemicals and is the direct responsibility of Subcommittee E27.04 on Available from National Technical Information Service (NTIS), 5301 Shawnee
Flammability and Ignitability of Chemicals. Rd., Alexandria, VA 22312, http://www.ntis.gov.
4
Current edition approved Dec. 1, 2019. Published January 2020. Originally Ural, E. A., and Brandes, E., “Towards A Global Standard For Flammability
approved in 1983. Last previous edition approved in 2011 as E918 – 83 (2011). Determination,” Proceedings of the 42nd Annual Loss Prevention Symposium,
DOI: 10.1520/E0918-19. Global Safety Congress, American Institute of Chemical Engineers, New Orleans,
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or LA, Apr. 6–10, 2008.
5
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Cashdollar, K. L., Zlochower, I. A., Green, G. M., Thomas, R. A., and
Standards vol
...

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: E918 − 83 (Reapproved 2011) E918 − 19
Standard Practice for
Determining Limits of Flammability of Chemicals at Elevated
1
Temperature and Pressure
This standard is issued under the fixed designation E918; 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 practice covers the determination of the lower and upper concentration limits of flammability of combustible
vapor-oxidant mixtures at temperatures up to 200°C and initial pressures up to as much as 1.38 MPa (200 psia). This practice is
limited to mixtures which would have explosion pressures less than 13.79 MPa (2000 psia).
1.2 This practice should be used to measure and describe the properties of materials, products, or assemblies in response to
heat and flame under controlled laboratory conditions and should not be used to describe or appraise the fire hazard or fire risk
of materials, products, or assemblies under actual fire conditions. However, results of this test may be used as elements of a fire
risk assessment which takes into account all of the factors which are pertinent to an assessment of the fire hazard of a particular
end use.
1.3 This standard may involve hazardous materials, operations, and equipment. This standard does not purport to address all
of the safety problems concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish
appropriate safety safety, health, and healthenvironmental practices and determine the applicability of regulatory limitations prior
to use.
1.4 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
2
2.1 ASTM Standards:
E681 Test Method for Concentration Limits of Flammability of Chemicals (Vapors and Gases)
E2079 Test Methods for Limiting Oxygen (Oxidant) Concentration in Gases and Vapors
2.2 Other Documents:
3
Bulletin 503 Bureau of Mines, “Limits of Flammability of Gases and Vapors,” NTIS AD701575
3
Bulletin 627 Bureau of Mines, “Flammability Characteristics of Combustible Gases and Vapors,” NTIS AD701576
3. Terminology
3.1 Definitions:
3.1.1 lower limit of flammability or lower flammable limit (LFL)—(LFL), n—the minimum concentration of a combustible
substance that is capable of propagating a flame through a homogeneous mixture of the combustible and a gaseous oxidizer under
the specified conditions of test.
3.1.2 upper limit of flammability or upper flammable limit (UFL)—(UFL), n—the maximum concentration of a combustible
substance that is capable of propagating a flame through a homogeneous mixture of the combustible and a gaseous oxidizer under
the specified conditions of test.
3.2 Definitions of Terms Specific to This Standard:
1
This practice is under the jurisdiction of ASTM Committee E27 on Hazard Potential of Chemicals and is the direct responsibility of Subcommittee E27.04 on
Flammability and Ignitability of Chemicals.
Current edition approved Aug. 1, 2011Dec. 1, 2019. Published August 2011January 2020. Originally approved in 1983. Last previous edition approved in 20052011 as
E918 – 83 (2005).(2011). DOI: 10.1520/E0918-83R11. 10.1520/E0918-19.
2
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’sstandard’s Document Summary page on the ASTM website.
3
Available from National Technical Information Service (NTIS), 5301 Shawnee Rd., Alexandria, VA 22312, http://www.ntis.gov.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
E918 − 19
3.2.1 propagation of flames—flames, n—as used in this practice, a combustion reaction that produces at least a 7 % rise of the
initial absolute pressure,pressure:
P
2
^1.07.
P
1
P
2
^1.07
P
1
NOTE 1—This 7 % rise in pressure corresponds to 1 psia (0.007 MPa) per atmosphere of initial pressure.
NOTE 2—The 7 % pressure criterion may not be appropriate for certain fuel and oxidant mixt
...