API RP 581 - 3rd Ed.2016 - Add.2-2020 - Risk-Based Inspection Methodology

RISK-BASED INSPECTION METHODOLOGY, PART 5—SPECIAL EQUIPMENT 5-3
[12] Lees, F.P., Loss Prevention in the Process Industries: Hazard Identification, Assessment and Control,
Butterworth-Heinemann, Second Edition, Reprinted 2001
[13] Lees, F. P., The Assessment of Human Reliability in Process Control, Conference on Human
Reliability in the Process Control Centre, Institution of Chemical Engineers, London, 4th edition, 2012
[14] IEC 61511, Functional Safety: Safety Instrumented Systems for the Process Industry Sector,
International Electrotechnical Commission, Geneva, Switzerland
[15] Trident, Report to the Institute of Petroleum on the “Development of Design Guidelines for Protection
Against Over-Pressures in High Pressure Heat Exchangers: Phase One”, Trident Consultants Ltd and
Foster Wheeler Energy, Report J2572, known as “The Trident Report”, 1993
[16] Nelson, Wayne B., Applied Life Data Analysis, John Wiley, 2003. ISBN: 978-0-471-64462-0
3 Pressure Vessels and Piping
POF
The procedures for POF calculations to be used are provided in Part 2. The POF as a function of time and
inspection effectiveness is determined using a GFF, a management systems factor, and DFs for the
applicable active damage mechanisms as described in Part, 1, Section 4.1.
COF
COF calculation procedures for two levels of consequence analysis are provided in Part 3, as described in
Part 1, Section 4.2. In both methods, the consequence analysis may be determined in consequence area or
in financial consequence. Consequences from flammable and explosive events, toxic releases, and
nonflammable and nontoxic events are considered based on the process fluid and operating conditions.
Risk Analysis
Risk as a function of time is calculated in accordance with Part 1, Section 4.3.1. The distribution of risks for
different components may be plotted on a risk matrix or iso-risk plot, as described in Part 1, Section 4.3.2
and Part 1, Section 4.3.2.3, respectively.
Inspection Planning Based on Risk Analysis
The procedure to determine an inspection plan is provided in Part 1, Section 4.4. This procedure may be
used to determine both the time and type of inspection to be performed based on the process fluid and
design conditions, component type and materials of construction, and the active damage mechanisms.