Process Hazard Analysis
1
Process hazard analysis is about applying the basic principles of probability and risk management to make long term valueadded decisions.
Starting Point
controlling the hazards of process.
The starting point for any good decisions coming for a process hazard analysis should be a shared understanding of what a process hazard analysis actually trying to achieve. When designing a complex process to operation safely yet productively, we need a process that everyone understands: one that facilitates discussion and decision. The challenge is that the process must be simple, intuitively understandable, apply consistently while not oversimplifying the complexities of how a process function. In this book we offer our approach that allows a team of managers, process designers, operators, engineers and decision makers to think through the design, identify the cause for hazards, understand the risks and consequences. A well executed process hazard analysis can become a shared language that allows you and your team to easily assess the risks and make decisions based on shared knowledge. Process hazard analysis is a key provision of process safety management. Employer is expected to document their facilities complies with recognized an generally accepted practices. As part of the documentation is a process hazard analysis that is exhaustive, systematic approach for identifying, evaluating, and
Risk-Based Decision Process Risk has two elements. Probability and Severity. Risk-based decision is choosing the best of a number of alternatives to maximize the resources available and minimize the risks. The value to risk-based decisions occurs not when you have complete control and knowledge of the future prospects but when you don’t. Process hazard analysis, in particular Hazard and Operability Study (HAZOP) and Layer of Protection Analysis (LOPA) incorporates the risk-based decision discipline with participatory decision making process.
4
Participatory Decision Making
2
Successful participatory decision making requires following a set of principles. Enforcing these principles will help you maximize the quality and value of a process hazard analysis.
Section 1
Participatory Decision Making Dynamic of Group Risk-based Decision Making Decision-making in projects almost always involves organizational teams to analyze the problem from a technical and operational standpoint. A HAZOP meets the challenges of implementing logical decisions with realistic risk assessment in the team environment. A structured approach provides direction, purpose, insight, and communication needed to arrive high quality decisions. High quality decisions along with a commitment to operationally sustainable recommendations will drive value in your organization in the long run. In order to achieve this, a HAZOP facilitator and the team must have an appreciation for the dynamic of group decision making. When you have a group of project managers, engineers and operators in a room, each
with a different perspective, two things generally happen with a similar dynamic: 1) Group can lose focus and needs to be re-focused Discussion can go off on tangents. Your team can lose focus and people can start losing confidence in the decision making process. A good facilitator knows when to focus the discussion to the problem at hand. 2) Opinions diverge then converge At the start of each scenario individual members of a group should contribute their own points of view. Not everyone will agree on a severity of a consequence or the likelihood of of an event. This is because everyone has different experience and backgrounds. This is a good thing. In a HAZOP, you want to get the best knowledge present from diverse perspectives before making a decision. The decisions that need the divergent thinking process the most are the difficult decisions. These are decisions that require large capital expenditures or majorly impact project schedule. But often times, divergent thinking is a valuable part of a HAZOP. This is why HAZOPs are done in team environments; to look at risks without the tunnel vision of an individual.
8
T i m e
Opinion & Focus
This never happens Fa c
ilit ato
Question: What is the likelihood of ...?
rg
uid
an
ce
Decision
This is going nowhere!
This always happens
Time
How can we to get here?!?
HAZOP
3
HAZOP is a shared decision making process for describing, visualizing and understand operational risks
Section 2
HAZOP Canvas
The HAZOP Canvas The HAZOP Canvas is a practical way to visual the interworking components of a HAZOP. We believe the HAZOP Canvas offers a simples tool for understanding and implementing a HAZOP. The HAOZP canvas comprises of eight building blocks. Each building blocks serve as the foundation to build strong logical arguments for risk-based decisions. The logical flow of the HAZOP discussion start with a topdown approach. Starting from a subsystem of a process - a node, by understanding the consequences and the likelihood of the consequence, a risk-based decision can be made with the cooperate risk matrix as the decision criteria set out by the risk owner (i.e. the owner and operator of the facility). The 8 building blocks and the logical sequence to build ensure an exhaustive risk identification and logical arguments are illustrated in the next pages:
19
The 8 building blocks 1
Node
A breakdown of a system into simpler subsystems to make the HAZOP more efficient.
2
Deviation
Abnormal operation that deviates from the design intent. Used as guide words to identify causes of hazards.
3
Cause
Causes that result in potential hazards.
4
Consequences
Hazardous consequences of an event.
5
Inherent Risk
Risk without any safeguards.
6
Safeguards
Things that can reduce the likelihood of a hazardous event.
7
Operational Risk Ranking
Risk when safeguards and conditional modifiers are accounted for.
8
Recommendations
Changes in process design or operations due to risk exceeding the tolerance of an organization.
Inlet Separation Gas Compression Chemical injection Test Emulsion Sour Water High Pressure Steam • Low Pressure Steam • Blanket Gas • Flare • • • • • •
• • • • • • • • • •
High Flow No Flow High Pressure Low Pressure High Level Low Level High Temperature Low Temperature Locations/Site Plan Operator Error
• Control loop malfunctions • Pump malfunctions • Loss of instrument air • Check valve stuck open • Operator omitted task • Trucker error
• Consider adding a high pressure safety shut-down • Consider adding additional operator rounds • Consider limiting access to non-essential personnel
• Overpressure of piping leading to loss of containment and H2S release resulting in fatality • Damage of compressor leading to production down time and equipment damage resulting in economic loss • Damage of storage tanks leading to loss of containment resulting in environmental damage • Pipeline rupture leading to oil in a fast moving river resulting in reputation damage
• High Risk Unacceptable without safeguards • Medium Risk Unacceptable without safeguards • Low Risk Acceptable without safeguards
• High Risk Recommendation required • Medium Risk Recommendation based on feasibility • Low Risk Acceptable, design adequate
• Conditional modifier: Operator in the area less than ten percent of the time • Enabling event: Ignition source less than ten percent chance • Safeguard: Pressure safety valve • Safeguard: Basic process control system • Safeguard: Safety instrumented system • Safeguard: Secondary containment
1 Node
Node 1 - Inlet
Node 1 - Inlet
Node 1 - Inlet
2 Deviation
3 Cause
4
5
Consequence
Inherent Risk Ranking
PV-111 fails closed
Over pressure of V-111 leading to equipment damage
High Flow
PV-111 fails closed
Over pressure of V-111 leading to environmental damage
High Flow
PV-111 fails closed
Over pressure of V-111 leading to potential fatality
High Flow
Creative thoughts
This work sheet provides a structured template preformatted with the eight building blocks - which allows you and your team to build a shared perspective on process risks. A HAZOP works best when there is diverse knowledge and experience from engineering and operations
6 Safeguards and Modifiers
S
L
RR
1
2
Low
Pressure Safety Valve
Med
Pressure Safety Valve
High
Pressure Safety Valve
3
5
3
5
Logical analysis
7
8
Operating Risk Ranking
Recommendations
S
L
RR
1
1
Low
None required.
Low
Consider adding a high pressure shutdown
Low
Consider adding a high pressure shutdown
3
5
1
1
Rational decisions
Logical analysis
Rational decisions
Left Brain
Prefrontal Cortex
Creative thoughts
Right Brain
I orchestrate thoughts and actions in accordance my goals. I make decisions.
I am creative and emotional. I think about “What if...”. I am fearful and a risk taker. I am rational and systematic. I think about causeconsequences. I think about costbenefits.
The role of faciliator
4
A facilitator need to understand all of the subtle details that go into a successful risk analysis by harnessing the immense knowledge and experience from the Process Hazard Analysis team.
Section 1
The role of faciliator Why have a facilitator? The job of a HAZOP facilitator is to help the team achieve the highest quality decisions possible. The facilitator needs to get full participation by guiding the team to form strong logical arguments and build sustainable agreements.
extended analysis often surfaces in a HAZOP because many people see only parts of a problem or opportunity. There can be confusion as to how things interact, what the likelihoods and root causes of failures are, what the consequences are, what is important and what is irrelevant to a risk-based decision. Information can be fragmentary, recommendations may not have been thought out, and consequences may not have been fully identified. The facilitator role is to provide a structure that cuts through much of the confusion and helps identify the real risks.
Encourage full participation Often times in group decision-making, people don’t say what they are really thinking. When someone speak out against the perceived consensus, they are taking a personal risk on their reputation. The facilitator has to understand the dynamic of the team, use logic, and draw on the best knowledge in the group to make a decision. Group brainstorming needs encouragement, not evaluation. Many people don’t understand this. If they notice a flaw in someone’s thinking, they point it out. Premature criticism is often inaccurate and stifling. When ideas are criticized before they are fully formed, many people feel discouraged and stop
Decision worth 41
Execute
5
Executing a high quality and efficient HAZOP requires the understanding of the level of involvement of each participants, the level of decision to be made and the scope of the analysis.
Objective
Mobilize
Focus
Description
Understand
Analysis
Decide
Implement
Organize the knowledge Brake down the process and information. in to simple easy-tounderstand subsystems.
Evaluate the risks from possible process deviations.
Make consistent and logical risk-based decisions.
Effective execute on the HAZOP recommendations.
Gather the people and engineering documents.
Identify hazardous causes and assess the risk before and after safeguards.
Align the corporate risk Reduce the operational appetite with the risk with sustainable operational risks. Decide actions. on actionable risk reduction measures.
HAZOP node design.
Examples
6
Examples from the oil and gas industry.
Section 1
Examples
Examples 1. SAGD Wellheads 2. Pipeline Manifolds 3. Gas-Liquid Separator 4. Heat Exchangers 5. Scrubber 6. Re-boiler 7. Gas Compression 8. Oil Storage 9. Rail Loading Terminal 10.Flare system 51
Examples 1: Oil Terminal
LT 100
Sales Oil
T-100 -Run
-Run
I
-ST/SP
-ST/SP
M
M
Sales Oil
M
M-100 B-100
Examples 2: Acid Gas Liquid Separator
Acid Gas
V-100 M
Acid Gas
LT 100
LAHH LH
Wet H.C. Wet H.C.
Drain P-100
Copyright
© Icaurs-ORM Published by Icarus-ORM Inc. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form. Printed in Canada
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About Icarus-ORM Inc. At Icarus-ORM, we eat, sleep and breathe operational risk management (ORM) day in and day out. As specialists in facilitation, analysis and decision support, we are uniquely positioned to meet and exceed your risk management needs. With a singular focus on operational risk management, our consulting practice obsesses over the delivering insight to our clients. We zero-in on operational risks management to produce one of the greatest return on investment.
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