1、Designation: G128/G128M 15Standard Guide forControl of Hazards and Risks in Oxygen Enriched Systems1This standard is issued under the fixed designation G128/G128M; the number immediately following the designation indicates the yearof original adoption or, in the case of revision, the year of last re
2、vision. A number in parentheses indicates the year of last reapproval.A superscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This guide covers an overview of the work of ASTMCommittee G04 on Compatibility and Sensitivity of Materialsin Oxygen-Enriche
3、d Atmospheres. It is a starting point forthose asking the question: “What are the risks associated withmy use of oxygen?” This guide is an introduction to the uniqueconcerns that must be addressed in the handling of oxygen.Theprincipal hazard is the prospect of ignition with resultant fire,explosion
4、, or both. All fluid systems require designconsiderations, such as adequate strength, corrosion resistance,fatigue resistance, and pressure safety relief. In addition tothese design considerations, one must also consider the ignitionmechanisms that are specific to an oxygen-enriched system.This guid
5、e outlines these ignition mechanisms and the ap-proach to reducing the risks.1.2 This guide also lists several of the recognized causes ofoxygen system fires and describes the methods available toprevent them. Sources of information about the oxygen hazardand its control are listed and summarized. T
6、he principal focusis on Guides G63, G88, Practice G93, and Guide G94. Usefuldocumentation from other resources and literature is also cited.NOTE 1This guide is an outgrowth of an earlier (1988) CommitteeG04 videotape adjunct entitled Oxygen Safety and a related paper byKoch2that focused on the recog
7、nized ignition source of adiabaticcompression as one of the more significant but often overlooked causes ofoxygen fires. This guide recapitulates and updates material in thevideotape and paper.1.3 The values stated in either SI units or inch-pound unitsare to be regarded separately as standard. The
8、values stated ineach system may not be exact equivalents; therefore, eachsystem shall be used independently of the other. Combiningvalues from the two systems may result in non-conformancewith the standard.1.4 This standard does not purport to address all of thesafety concerns, if any, associated wi
9、th its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use. For specificprecautionary statements see Sections 8 and 11.NOTE 2ASTM takes no position respecting the valid
10、ity of anyevaluation methods asserted in connection with any item mentioned in thisguide. Users of this guide are expressly advised that determination of thevalidity of any such evaluation methods and data and the risk of use ofsuch evaluation methods and data are entirely their own responsibility.2
11、. Referenced Documents2.1 ASTM Standards:3D2512 Test Method for Compatibility of Materials withLiquid Oxygen (Impact Sensitivity Threshold and Pass-Fail Techniques)D2863 Test Method for Measuring the Minimum OxygenConcentration to Support Candle-Like Combustion ofPlastics (Oxygen Index)D4809 Test Me
12、thod for Heat of Combustion of LiquidHydrocarbon Fuels by Bomb Calorimeter (PrecisionMethod)G63 Guide for Evaluating Nonmetallic Materials for Oxy-gen ServiceG72 Test Method for Autogenous Ignition Temperature ofLiquids and Solids in a High-Pressure Oxygen-EnrichedEnvironmentG74 Test Method for Igni
13、tion Sensitivity of NonmetallicMaterials and Components by Gaseous Fluid ImpactG86 Test Method for Determining Ignition Sensitivity ofMaterials to Mechanical Impact in Ambient Liquid Oxy-gen and Pressurized Liquid and Gaseous Oxygen Envi-ronmentsG88 Guide for Designing Systems for Oxygen ServiceG93
14、Practice for Cleaning Methods and Cleanliness Levelsfor Material and Equipment Used in Oxygen-EnrichedEnvironmentsG94 Guide for Evaluating Metals for Oxygen ServiceG124 Test Method for Determining the Combustion Behav-ior of Metallic Materials in Oxygen-Enriched Atmo-spheres1This guide is under the
15、jurisdiction ofASTM Committee G04 on Compatibilityand Sensitivity of Materials in Oxygen Enriched Atmospheres and is the directresponsibility of Subcommittee G04.02 on Recommended Practices.Current edition approved Oct. 1, 2015. Published November 2015. Originallyapproved in 1995. Last previous edit
16、ion approved in 2008 as G128 02(2008). DOI:10.1520/G0128_G0128M-15.2Koch, U. H., “Oxygen System Safety,” Flammability and Sensitivity ofMaterials In Oxygen-Enriched Atmospheres , Vol 6,ASTM STP1197,ASTM, 1993,pp. 349359.3For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact
17、ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1G126 Terminology Relating t
18、o the Compatibility and Sensi-tivity of Materials in Oxygen Enriched AtmospheresG175 Test Method for Evaluating the Ignition Sensitivityand Fault Tolerance of Oxygen Pressure Regulators Usedfor Medical and Emergency Applications2.2 ASTM Adjuncts:Video: Oxygen Safety42.3 ASTM CHETAH Analytical Comput
19、er Software Pro-gram:CHETAH Chemical Thermodynamic and Energy ReleaseEvaluation52.4 Compressed Gas Association (CGA) Standards:6G-4.1 Cleaning Equipment for Oxygen ServiceG-4.4 Oxygen Pipeline and Piping Systems2.5 European Industrial Gas Association (EIGA) Stan-dards:733/XX/E Cleaning of Equipment
20、for Oxygen Service13/XX/E Oxygen Pipeline and Piping Systems2.6 National Fire Protection Association (NFPA) Stan-dards:851 Standard for the Design and Installation of Oxygen-FuelGas Systems for Welding, Cutting and Allied Processes53 Recommended Practice on Material, Equipment, andSystems Used in Ox
21、ygen Enriched Atmospheres55 Compressed Gases and Cryogenic Fluids Code99 Health Care Facilities Code2.7 Military Specifications:9MIL-PRF-27617 Performance Specification, Grease, Air-craft and Instrument, Fuel and Oxidizer ResistantDOD-PRF-24574 (SH) Performance Specification, Lubri-cating Fluid for
22、Low and High Pressure Oxidizing GasMixtures3. Terminology3.1 Definitions:3.1.1 See Terminology G126 for the terms listed in thissection.3.1.2 autoignition temperature (AIT), nthe lowest tem-perature at which a material will spontaneously ignite in anoxygen-enriched atmosphere under specific test con
23、ditions.3.1.3 hazard, nsource of danger; something that couldharm persons or property.3.1.4 ignition mechanisms, nThese are the specific physi-cal attributes and system conditions that cause the initial firewithin a system. A system designer must evaluate an oxygen-enriched system for all possible i
24、gnition mechanisms. Acommon ignition mechanism for metals is particle impact. Acommon ignition mechanism for non-metals is adiabatic com-pression.3.1.5 ignition temperature, nthe temperature at which amaterial will ignite under specific test conditions.3.1.6 impact-ignition resistance, nthe resistan
25、ce of a ma-terial to ignition when struck by an object in an oxygen-enriched atmosphere under a specific test procedure.3.1.7 nonmetal, na class of materials consisting ofpolymers, certain composite materials (polymer matrix andbrittle matrix composites in which the most easily ignitedcomponent is n
26、ot a metallic constituent), ceramics, and variousorganic and inorganic oils, greases, and waxes. nonmetallic,adj.3.1.8 oxidant compatibility, nthe ability of a substance tocoexist at an expected pressure and temperature with both anoxidant and a potential source(s) of ignition within a riskparameter
27、 acceptable to the user.3.1.9 oxygen-enriched, adjcontaining more than 23.5 molpercent oxygen.3.1.9.1 DiscussionOther standards such as those pub-lished by NFPA and OSHA differ from this definition in theirspecification of oxygen concentration.3.1.10 qualified technical personnel, npersons such asen
28、gineers and chemists who, by virtue of education, training,or experience, know how to apply the physical and chemicalprinciples involved in the reactions between oxidants and othermaterials.3.1.11 risk, nprobability of loss or injury from a hazard.3.1.12 system conditions, nthe physical parameters o
29、f aspecific system. These can include local and system-widepressure, temperature, flow, oxygen concentration, and others.3.1.13 wetted material, nany component of a fluid systemthat comes into direct contact with the system fluid.4. Significance and Use4.1 The purpose of this guide is to introduce t
30、he hazards andrisks associated with oxygen-enriched systems. This guideexplains common hazards that often are overlooked. It pro-vides an overview of the standards and documents produced byASTM Committee G04 and other knowledgable sources aswell as their uses. It does not highlight standard test met
31、hodsthat support the use of these practices. Table 1 provides agraphic representation of the relationship of ASTM G04standards. Table 2 provides a list of standards published byASTM and other organizations.4.2 The standards discussed here focus on reducing thehazards associated with the use of oxyge
32、n. In general, they arenot directly applicable to process reactors in which the delib-erate reaction of materials with oxygen is sought, as in burners,bleachers, or bubblers. Other ASTM Committees and products(such as the CHETAH program5) and other outside groups aremore pertinent for these.4.3 This
33、 guide is not intended as a specification to establishpractices for the safe use of oxygen. The documents discussed4Available from ASTM International Headquarters. Order Adjunct No.ADJG0088.5Available from ASTM International Headquarters, 100 Barr Harbor Drive,West Conshohocken, PA 19428, Order # DS
34、C 51C, Version 7.2.6Available from Compressed Gas Association (CGA), 4221 Walney Rd., 5thFloor, Chantilly, VA 20151-2923, http:/.7Available from European Industrial GasAssociation, Publication de la SoudureAutogene, 32 Boulevard de la Chapelle, 75880 Paris Cedex 18, France.8Available from National F
35、ire Protection Association (NFPA), 1 BatterymarchPark, Quincy, MA 02169-7471, http:/www.nfpa.org.9Available from Standardization Documents Order Desk, DODSSP, Bldg. 4,Section D, 700 Robbins Ave., Philadelphia, PA 19111-5098, http:/dodssp.daps.dla.mil.G128/G128M 152here do not purport to contain all
36、the information needed todesign and operate an oxygen-enriched system safely. Thecontrol of oxygen hazards has not been reduced to handbookprocedures, and the tactics for using oxygen are not simple.Rather, they require the application of sound technical judg-ment and experience. Oxygen users should
37、 obtain assistancefrom qualified technical personnel to design systems andoperating practices for the safe use of oxygen in their specificapplications.5. Summary5.1 Oxygen and its practical production and use are re-viewed. The recognized hazards of oxygen are described.Accepted and demonstrated met
38、hods to reduce those hazardsare reviewed. Applicable ASTM standards from CommitteeG04 and how these standards are used to help mitigateoxygen-enriched system hazards are discussed. Similar usefuldocuments from the National Fire Protection Association, theCompressed Gas Association, and the European
39、Industrial GasAssociation also are cited.6. Oxygen6.1 Oxygen is the most abundant element, making up 21 %of the air we breathe and 55 % of the earths crust. It supportsplant and animal life. Oxygen also supports combustion, causesiron to rust, and reacts with most metals. Pure oxygen gas iscolorless
40、, odorless, and tasteless. Liquid oxygen is light blueand boils at 183C 297F under ambient pressure.6.2 Oxygen has many commercial uses. For example, it isused in the metals industry for steel making, flame cutting, andwelding. In the chemical industry it is used for production ofsynthetic gas, gaso
41、line, methanol, ammonia, aldehydes, alco-hol production, nitric acid, ethylene oxide, propylene oxide,and many others. It is also used for oxygen-enriched fuelcombustion and wastewater treatment. For life support systemsit is used in high-altitude flight, deep-sea diving, clinicalrespiratory therapy
42、 or anesthesiology, and emergency medicaland fire service rescues.7. Production and Distribution7.1 Most oxygen is produced cryogenically by distillingliquid air. The demand for ultrahigh purity within the semicon-ductor industry has led to a more thorough distillation ofcryogenic oxygen. Further, n
43、oncryogenic production has be-come significant in recent years. The principal differenceamong these sources of oxygen is the resulting oxygen puritydetailed below. The hazards of oxygen are affected greatly bypurity and, in general, higher purity is more hazardousHowever, fire events can and do occu
44、r in any oxygenenrichedatmosphere.7.2 Cryogenic ProductionCryogenically produced oxy-gen is distilled in a five-step process in which air is: (1) filteredto remove particles; (2) compressed to approximately 700 kPa100 psig pressure; (3) dried to remove water vapor andcarbon dioxide; (4) cooled to 16
45、0C 256F to liquefy itpartially; and (5) distilled to separate each component gas. Theend products are oxygen, nitrogen, and inert gases such asargon and neon; the principal secondary products are nitrogenand argon. Commercial oxygen is produced to a minimum99.5 % purity, but typical oxygen marketed
46、today is morelikely to be near 99.9 % purity.7.2.1 For high-volume bulk users, such as steel or chemicalplants, the oxygen plant is often adjacent to the users facility,and gaseous oxygen is delivered by pipeline at low to mediumpressures, usually 700 to 5500 kPa 100 to 800 psig.7.2.2 Cryogenic liqu
47、id oxygen is delivered by trailer toother large-volume users, who utilize liquid storage tanks, thenvaporize the liquid, and distribute the gas (Fig. 1 and Fig. 2).TABLE 1 Relationship of ASTM Standards for Oxygen-Enriched SystemsG128/G128M 1537.2.3 Most users buy oxygen in small amounts, usually in
48、20-MPa or 2500-psig cylinders, and use it directly from thecylinders or through manifolds and a piping distributionsystem. Usually, the pressure is reduced with a regulator at thecylinder or manifold.7.3 Ultrahigh-Purity OxygenThere are a few markets thatrequire high- and ultrahigh-purity oxygen. Hi
49、gh-purity oxygentypically delivers 99.99 % purity, whereas the demands of thesemiconductor industry have resulted in the marketing of99.999 % purity oxygen.7.4 Noncryogenic ProductionNoncryogenic oxygen pro-duction processes include pressure swing adsorption (PSA),vacuum swing adsorption (VSA), and membrane separation. Ingeneral, these methods produce oxygen less pure than cryo-genically produced oxygentypically 97 %, with the balancebeing nitrogen, argon, and carbon dioxide. However, theseprocesses use less power and offer a
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