API RP 90-1

Description

This document (formerly RP 90) covers the management of annular casing pressure in offshore wells, including thermal casing pressure, sustained casing pressure (SCP) and operator-imposed pressure. It also addresses monitoring, diagnostic testing, the establishment of a maximum allowable wellhead operating pressure (MAWOP) and documentation of annular casing pressure for the various types of wells that occur offshore. Included is a discussion of risk assessment methodologies that can be used for the evaluation of individual well situations where the annular casing pressure is not within the MAWOP guidelines. Also included are guidelines in which a broad range of casing annuli that exhibit annular pressure can be managed in a routine fashion while maintaining an acceptable level of risk.