Risk Management

Risk Management


Risk-based Inspection (RBI) is a decision-making technique for inspection planning based on risk – comprising the consequence of failure (CoF) and probability of failure (PoF). It is a formal approach designed to aid the development of optimized inspection, and recommendations for monitoring and testing plans for production systems. It provides focus for inspection activity, to address explicitly the threats to the integrity of the asset and its capability to generate revenue through production.

RBI is carried out for piping and vessels, including heat exchangers, tanks, pressure vessels, and filters. The scope of the RBI encompasses all pressure systems in the plant, whether hydrocarbon-containing or utility.

To carry out the RBI analysis for each item, the consequences of failure (CoF) and probability of failure (PoF) are assessed separately. The two are then combined to obtain risk of failure.This evaluation is carried out separately for Safety (addressing personnel death and injury), Environmental (addressing damage to the environment) and Economic (addressing financial loss).


IPMC carries out underwater inspection using visual techniques, magnetic particles techniques, ultrasonic techniques, radiography and corrosion potential measurements. In getting optimal inspection results in underwater inspection, IPMC makes use of divers, remotely controlled vehicles and manned submersibles which produce high quality visual and photographic inspections.

For fixed offshore structures, IPMC makes use of periodic overflights of the water surface above the pipeline to observe any indication of leakage. IPMC annually tests each pipeline under cathodic protection to determine that it meets standard requirements.


IPMC successfully implements RBI using industry best practice techniques in the following areas:

1. Determining all ‘active’ and ‘potential’ damage mechanisms for each item, the failure mode for each of the identified damage mechanisms in order to evaluate realistically the ‘consequence of failure’.

2. The methodology must ensure reliable assessment of ‘probability of failure’ and the risk profile for each of the ‘active’ and ‘potential’ damage mechanisms identified for an item.

3. From the assessment of the risk profile for each of the damage mechanisms, the optimized inspection interval for the item must be reliably evaluated against an acceptable risk profile and predefined time frame.

4. Setting specific ‘ground rules’ within the team study process to ensure consistency in application of the RBI technology and the output

5. Defining and implementation auditing of the operational limits of key process parameters and maintenance activities (e.g., paint coatings, fire-cladding, insulation seal).

6. Ensuring that the study considers confidence levels the team has in the assessment,which may be reduced, for e.g. owing to limited availability of data. The inspection interval must therefore be adjusted accordingly.

7. The RBI team study must also include for the development of a detailed inspection plan with consideration and specification of reliable NDT methods linked to the damage mechanisms. Inspection plans must consider NDT capabilities & effectiveness.

8. The process must manage the transfer from current inspection plan to RBI driven inspection plan with consideration of the requirements of governing local legislations.

9. For high consequence items, speculative inspections and inspection sampling are always considered within the overall inspection programme in order to allow for the unexpected.

10. Procedures are always put in place at plant site to ensure that the RBI study output and the management of future reviews and updates are embedded into the site practices.

IPMC’s Risk based inspection methodology carried out using methods that are qualitative or quantitative. IPMC’s risk-based inspection efforts are carried out using a blend of both the methods and, hence, called semi-quantitative method.