This publication serves the interest of those associated or concerned with air separation plant operations and applies to safety in the design, location, construction, installation, operation, and maintenance of cryogenic air separation plants. Emphasis is placed on equipment and operational and maintenance features that are specific to cryogenic air separation processes. Limited coverage is given to plant equipment such as air compressors, which are used in other industrial applications and for which safe practices in design, installation, and use have already been established elsewhere. Further, as this publication is not intended as a universal safe practice manual for specific design and safety features, it is also important to refer to the operating manuals of the equipment suppliers.

Any new design and installation requirements contained in this edition only apply to new installations begun after the time of publication and not to existing installations. However, new requirements and recommendations may be considered by the user for existing operating units or those in the project phase.

The following are excluded from this publication:

• cylinder filling facilities;
• rare gas purification systems; and
• product transmission piping outside the plant boundaries.