Leakages from flexible hoses may result in negative consequences, ranging from a slight nuisance to a catastrophic incident. Therefore, effective in-service inspection is necessary to manage hose failure risks to a tolerable level.
By employing a Risk-Based Inspection (RBI) strategy, inspection activities and resources can be focused on the systems that pose the most risk. While ineffective or needless inspection work can be avoided or eliminated.
Following RBI steps can be implemented to determine the frequency of inspection/replacement of flexible hoses.
1. Collect Important Data & Specification
The first step is to collect key data and specifications for each hose. The data should include the following:
- Location of the hose
- Installation date
- Hose type/material
- Fluid and hazard(s) (e.g., toxic, flammable, corrosive, non-hazardous)
- Pressure/temperature
- Static (not normally moved / connected / disconnected)
- Dynamic (frequently moved /connected / disconnected)
It is a good practice to label each hose and include all the information on the label.
2. Assess the Consequences of Hose Failure
Allocate the most appropriate category, C1 – C5, using the guidance in the table below.
3. Assess the Probability of Hose Damage
Allocate the most appropriate category, P1 – P3, using the guidance in the table below.
4. Assign a Risk Classification
A risk rating must be determined for each system assessed based on the following:
Risk Rating = Probability of Hose Damage x Consequences of Failure
Assign a risk classification using the table below.
5. Implement an Inspection / Replacement Plan
An inspection plan can be determined for each hose based on the results of the RBI assessment. Before defining any inspection frequency, manufacturer recommendations and applicable regulatory requirements must be considered. As a general guideline, you can implement an inspection/replacement plan using the table below:
