PURPOSE a. This NPG is published for the purpose of establishing an outline of inservice inspection and recertification procedures for ground based, unfired pressure vessels and systems. It shall not replace the normal routine repair and maintenance programs now in effect.

b. Recommendations for categorizing systems and components, baseline inspection and recertification time intervals are presented in tabular form and a type and format of documentation is recommended.

APPLICABILITY. It is intended that each NASA Center use this guide and other applicable documents to define the detailed requirements and procedures for the specific vessels and systems over which it has cognizance.