4.1 The purpose of this guide is to introduce the hazards and risks associated with oxygen-enriched systems. This guide explains common hazards that often are overlooked. It provides an overview of the standards and documents produced by ASTM Committee G04 and other knowledgable sources as well as their uses. It does not highlight standard test methods that support the use of these practices. Table 1 provides a graphic representation of the relationship of ASTM G04 standards. Table 2 provides a list of standards published by ASTM and other organizations.

4.2 The standards discussed here focus on reducing the hazards associated with the use of oxygen. In general, they are not directly applicable to process reactors in which the deliberate 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 are more pertinent for these.

4.3 This guide is not intended as a specification to establish practices for the safe use of oxygen. The documents discussed here do not purport to contain all the information needed to design and operate an oxygen-enriched system safely. The control of oxygen hazards has not been reduced to handbook procedures, and the tactics for using oxygen are not simple. Rather, they require the application of sound technical judgment and experience. Oxygen users should obtain assistance from qualified technical personnel to design systems and operating practices for the safe use of oxygen in their specific applications.

1.1 This guide covers an overview of the work of ASTM Committee G04 on Compatibility and Sensitivity of Materials in Oxygen-Enriched Atmospheres. It is a starting point for those asking the question: “What are the risks associated with my use of oxygen?” This guide is an introduction to the unique concerns that must be addressed in the handling of oxygen. The principal hazard is the prospect of ignition with resultant fire, explosion, or both. All fluid systems require design considerations, such as adequate strength, corrosion resistance, fatigue resistance, and pressure safety relief. In addition to these design considerations, one must also consider the ignition mechanisms that are specific to an oxygen-enriched system. This guide outlines these ignition mechanisms and the approach to reducing the risks.

1.2 This guide also lists several of the recognized causes of oxygen system fires and describes the methods available to prevent them. Sources of information about the oxygen hazard and its control are listed and summarized. The principal focus is on Guides G63, G88, Practice G93, and Guide G94. Useful documentation from other resources and literature is also cited.

Note 1: This guide is an outgrowth of an earlier (1988) Committee G04 videotape adjunct entitled Oxygen Safety and a related paper by Koch2 that focused on the recognized ignition source of adiabatic compression as one of the more significant but often overlooked causes of oxygen fires. This guide recapitulates and updates material in the videotape and paper.

1.3 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard.

1.4 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 and health practices and determine the applicability of regulatory limitations prior to use. For specific precautionary statements see Sections 8 and 11.

Note 2: ASTM takes no position respecting the validity of any evaluation methods asserted in connection with any item mentioned in this guide. Users of this guide are expressly advised that determination of the validity of any such evaluation methods and data and the risk of use of such evaluation methods and data are entirely their own responsibility.