8

Process Safety Barriers – Monitoring, Control and Audit

Approximate Learning Time

 

Introduction

In this unit we look at the essential attributes of an effective Process Safety monitoring, control and audit system.

We revisit the ‘Swiss cheese’ model, and bring in once again the concepts of Active Failures and Latent Conditions.

 

Activity

Case Study on Audit, Assurance, Management Review and Intervention

 
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  • 8.2

    Process Safety Barriers – Monitoring, Control and Audit

    Audit, Assurance, Management Review and Intervention

    The essential attributes of an effective monitoring, control and audit system are defined in Element 20: ‘Audit, Assurance, Management Review and Intervention’ of the Energy Institute High Level Framework for Effective Process Safety Management.

    Click on the Resources icon and then follow the link to the Energy Institute’s High Level Framework for Process Safety Management, then scroll down to element 20.

     
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  • A Review

    As previously discussed, barrier failures (the Swiss Cheese Holes) can be Active Failures or Latent Conditions (see unit 3).

    The Process Safety Barrier model
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  • Revisiting two important concepts

    Latent Conditions

    Latent conditions are error conditions (such as design and maintenance, as well as inspection, procedural or organisational shortcomings) that are present within the system some time before the onset of a recognisable accident sequence.

    They may lie dormant for long periods before combining with active failures to allow penetration of all the barriers. In other words, all the Swiss Cheese holes are aligned.

    Active Failures

    Active Failures are the unsafe acts committed by those people at the sharp end, predominantly operators and maintenance technicians. These can be lapses, mistakes or procedural violations. They have an immediate, but usually short-lived impact on the defensive barriers.

    They often occupy the spotlight on subsequent accident investigations as they tend to be the immediate ‘triggering event’.

     

    Well done. You have reached the end of Unit 8.

    Proceed to Unit 9 or return to the Main Menu