What Sets API 580 Apart from API 581?
While API 580 and API 581 complement each other, they offer distinct guidelines. API 580 primarily centers on risk-based inspection, whereas API 581 focuses on asset integrity management, employing calculation-based approaches.
Here’s a breakdown of the differences:
Scope
API 580 targets fixed equipment in the refining and petrochemical industries. In the other hand, API 581 is applicable to a wider range of equipment and industries, with some adjustments and extensions.
Focus
API 580 concentrates on managing risk at the equipment level. While API 581 utilizes quantitative RBI methods, such as Probability of Failure (PoF) and Consequences of Failure (CoF) calculations, to support the minimum guidelines outlined in API 580.
Approach
API 580 follows a qualitative approach while API 581 adopts a quantitative approach.
Editions
Both API 580 and API 581 were updated to their 3rd editions in 2016.
Coverage
API 580 includes:
- Principles and benefits of RBI
- The RBI process
- Roles and responsibilities of RBI personnel
- Maintaining RBI program guidelines
- Inspection strategies (including prioritization and maintenance based on risk ranking)
- Equipment identification and categorization
- Selection of appropriate inspection techniques
Further, API 580 also includes risk assessment involving the assessment of probability and consequences of failure.
Meanwhile API 581 encompasses:
- Methodology for quantitative risk assessments
- Identification of potential damage mechanisms and failure modes
- Calculation of PoF and CoF
- Use of risk matrices for equipment prioritization in inspections and maintenance
- Inspection plans based on risk assessment results (including inspection techniques and frequencies), and
- Criteria for equipment replacement or repair based on RBI results.
All in all, API 581 also addresses the utilization of RBI outcomes for risk management, including the implementation of risk mitigation strategies.