Reducing safety risks thanks to RBI and the integrity operating window

Reducing safety risks, extending inspection intervals and reducing the scope of maintenance stops thanks to Risk Based Inspections and integrity operating window monitoring

Lerend Netwerk RBI

Inspections are carried out to gain an insight into possible integrity problems of static equipment (pressure vessels, pipelines, storage tanks, etc.) in plants. Nowadays, most inspections are carried out during a major maintenance stop. The employees enter the confined spaces and carry out inspections using various techniques, which entails safety risks. Moreover, many more measures need to be taken to send an employee into a vessel safely, which results in longer downtimes and higher costs.

Another factor is that many companies carry out their inspections on a time basis (i.e. once every 4, 6, etc. years). Often, these periodic inspections are mandatory due to legislation or requirements from the business. In this way, these inspections sometimes even become the main reason for a maintenance stop. We often find that the findings of such periodic inspections are similar to those of the previous time.
The question then arises whether an installation can no longer be kept in service if the inspections are made on the basis of risk of integrity rather than on the basis of elapsed time.

The methodology of Risk Based Inspections (RBI) offers a solution for both safety, environment (less waste) and economic aspects. Applying the RBI method also leads to fewer surprises: fewer integrity incidents and fewer leaks, which means fewer stops are needed. It also leads to lower costs, but above all to much better performance in terms of safety and the environment.

In the Netherlands, various chemical companies have succeeded in carrying out their inspections more intelligently (and therefore with fewer safety risks and costs) by applying RBI, with the approval of the 'Notified Bodies' (NOBOs) and the Dutch government.

How can we also increase the inspection intervals in Belgium thanks to RBI and digital monitoring of the Integrity Window and in this way strengthen the competitive position of Belgian Chemistry?

What do we need for RBI and the Integrity Window? 

The Chemical Risk Department already asks to map what can fail (RBI) in the process installations. If you can already monitor the risk factors well continuously, and you can operate within the damage-free zone, then the risks are actually under control and an internal periodic visual inspection is less relevant (and you could therefore reduce the inspection frequency and/or the inspection scope). The integrity operating window will have to be determined for various assets (or even sometimes per asset). And to be able to adjust in real time, a monitoring of digital sensors and/or measurements linked to these integrity operating windows is needed. This monitoring visualises the status of the inspection, trends from measuring points and any barriers that have been breached.

How to tackle this?

In order to realise this in Flanders as well, BEMAS is setting up a working group in which asset owners, inspection bodies, NOBOs and the Flemish government will consult each other.
Sitech Services, a service provider in the process industry which recently won the BEMAS Asset Performance 4.0 award for the way in which RBI was used in combination with monitoring the Integrity Operating Window, is helping to guide the working group. Sitech is a technical service provider on the Chemelot site (the Netherlands) and beyond. Sitech has extensive experience with the proposed set-up.

What are we going to do?

Introduction session

  • Presentation 'How does RBI contribute to the extension of inspection intervals at Dutch companies?

  • Round table discussion with participants from the Flemish process industry

    • Participants share how RBI is currently applied

    • Where are the challenges with regard to RBI?

    • To what extent is there already a monitoring of the Integrity Operating Window?

    • Is there a need to extend legal inspection intervals?

    • What is needed to evolve towards a more dynamic risk management and dynamic inspection intervals?

    • Further agreements and explanations in the next sessions

Drafting of a joint ambition note for an RBI-based dynamic management of inspection intervals

  • The impact of monitoring the Integrity Operating Window
  • To which (frequently occurring) equipment and in which situations can this be applied?
  • Estimation of the possible impact at the Flemish level
    • Safety
    • Environment
    • Economic

Consultation with competent government services

  • Presenting the concept and the ambition note
  • Ask for input and opinion on an RBI-based dynamic management of inspection intervals
  • Adapt the memorandum of ambition to this

Consultation with inspection bodies

  • Present the concept and the note of ambition
  • Ask for input
  • Ask for willingness to apply in a pilot with RBI-based dynamic management of inspection intervals

Final version of the mission statement and scoping of a possible follow-up trajectory

  • Drafting of the final version of the mission statement in which the possibilities and impact of RBI-based dynamic management of inspection intervals for the Flemish process industry are made clear
  • Scoping of a possible follow-up trajectory
    • Proposal of possible concrete cases
    • Proposal of inspection bodies
    • Proposal in possible support in the realisation of the cases
    • Checking the willingness of participating asset owners to actually realise a case
    • Possible follow-up steps and follow-up

Public presentation of the Ambition Statement

After the project:

  • Participants can opt to start with RBI-based dynamic management of inspection intervals
  • Feedback session in which the first results and experiences are shared with each other
  • Follow-up steps towards government and inspection authorities


What is expected of the participants?

  • Participate in the sessions
  • Give a presentation of the current RBI approach and the current periodic TA strategy
  • Discuss whether and how the Integrity Operating Windows are currently determined and monitored
  • Assess the possibilities and potential of RBI-based dynamic management of inspection intervals in the company
  • Actively participate in the consultation with the competent government services regarding inspection intervals
  • Actively participate in consultations with recognised inspection organisations (NoBo's) to find out under which conditions they can agree to the transition from Time Based to Risk Based Inspections of static equipment based on monitoring of the Integrity Operating Windows.

More information?

Are you an Integrity Manager, Integrity Engineer, Asset Manager, Reliability Engineer or Environmental Manager in the chemical industry or in chemical logistics? Then this community is for you.

Practical info





The introductory session took place on 7 April 2022 at Link 21 (Welvaartstraat 14, 2200 Herentals).

13:30 Welcome

14:00 Start of the session

16:30 Scheduled end

The next sessions will always take place at one of the participants' premises.
The dates, timing and location of these sessions will be determined during the introduction session.

In collaboration with

BEMAS Corporate Sponsors