HAZARD & OPERABILITY STUDIES
Mike Lihou - Lihou Technical & Software Services
Click on the INTRODUCTION link to read from the beginning, or on an index entry to go directly to that section.
CONTENTS
| INTRODUCTION | General concept, usage and terminology |
| Potential Hazard AND Operability Problems | Improved Operability - an important benefit of Hazop Studies |
| Deviation from design intent | Explanation of basic Hazop Study terminology |
| Industries in which the technique is employed | The origin of the technique, and some of the industries in which Hazops are employed |
| The reasons for such widespread use of Hazops | How the Hazop technique complements and extends existing design practices |
| THE BASIC CONCEPT | Systematic analysis that encourages use of imagination |
| Keywords | A unique and essential aspect of the Hazop Study methodology |
| Primary Keywords | What they represent - Examples of process and operationally oriented keywords |
| Secondary Keywords | Used in combination with Primary Keywords - Examples - Meanings - Relevance |
| HAZOP STUDY METHODOLOGY | Information recorded - The Hazop Review Procedure - Recording Styles |
| Information to be Recorded | Layout of a typical Hazop Study recording sheet |
| Deviation | Essentially, the combination of Keywords |
| Cause | Example of a Cause |
| Consequence | Important aspects to bear in mind when assessing and recording the Consequence |
| Safeguards | What to consider when identifying Safeguards |
| Action | Types of Actions - Important points to take into account when formulating an Action |
| The Hazop Procedure | Flow Diagram illustrating the systematic and iterative Hazop Study process |
| Full Recording versus Recording by Exception | Describes two styles of recording Hazop information |
| THE HAZOP TEAM | Ideal number of members - Composition of the study team |
| PREPARATORY WORK | The importance of preparation |
| Assemble the data | Typical documentation required for a Hazop Study |
| Understand the subject | An essential aspect, the foundation upon which successful preparation is based |
| Subdivide the plant and plan the sequence | Guidelines for Noding and planning the order of study |
| Mark the drawings | Colour-coding of Nodes |
| Devise a list of appropriate Keywords | Building a comprehensive but concise Hazop keyword list |
| Prepare Node Headings and Agenda | Information to include in Node Headings, and the importance of an Agenda |
| Prepare a timetable | Guidelines for planning a timetable, and its importance during lengthy Hazop Studies |
| Select the team | Core and part-time Hazop Study team members |
| RUNNING A HAZOP STUDY | Guidelines for leading an efficient, comprehensive and successful Hazop Study |
| THE REPORT | The importance of the Hazop Study Report - Information and documentation to be included |
| THE ACTION FILE AND REVIEW MEETINGS | Maintaining an Action File throughout the Review process |