HAZOP Setup at a Glance
HAZOP components
The Operational Risk Administration menu includes four options under HAZOP Setup. Administrators can use these components to simplify and expedite data entry in risk assessment worksheets, and to ensure quality and consistency in Hazard and Operability (HAZOP) study risk assessments:
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- Parameters are measurable factors, or variables, of a system, process, or condition. In engineering or process safety, they often refer to operating conditions like temperature, pressure, flow rate, or concentration, that must be controlled to ensure safe and efficient operation. Parameters are paired with guidewords for use in deviation templates.
- Guidewords are standardized words or phrases used in Hazard and Operability (HAZOP) studies to systematically identify potential deviations from design intent. Common guidewords are No, More, Less, As well as, etc. Guidewords are paired with parameters for use in deviation templates; each pair describes a deviation from normal operation. For example: No flow, More pressure, Less flow.
- Deviation Templates are used to pair individual parameters and guidewords together to help teams document and analyze deviations from expected or normal operating conditions. They can be reused as necessary.
- Nodes, in the context of process safety or systems analysis, are specific points or sections of a process (for example, a pump, reactor, or pipeline segment) selected for detailed review. Each node is analyzed for potential hazards using tools like HAZOP studies, with a focus on how deviations may occur and what their impact could be. Nodes, when connected with deviation templates in risk worksheets, facilitate entry of multiple causes.
What does this process look like in practice?
Deviation templates in HAZOP risk assessments help a team identify potential problems in a process by asking structured questions about what could go wrong. The guide words and parameters spark discussion and uncover hidden risks. When preparing for risk evaluation, the risk assessment worksheet can be pre-populated with guideword/parameter pairs via deviation templates to save time.
Consider this example for a pipe carrying hot water:
1. Design "intent"
A pipe carries hot water at a certain pressure and flow rate. This is the design "intent" (how the system is supposed to work).
2. Pair parameters and guidewords
Use guideword/parameter pairs (the deviation template) to form questions:
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- No (e.g., no flow)
- More (e.g., more pressure)
- Less (e.g., less temperature)
- Reverse (e.g., flow in the wrong direction)
- Other than (something unexpected)
3. Ask "what if" questions
Ask “what if” questions to uncover deviations from normal operation:
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- What if there’s no flow?
- What if the pressure is more than normal?
- What if the temperature is less than expected?
4. Identify causes, consequences
For each deviation, the team discusses:
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- What could cause this? (e.g., a valve stuck closed)
- What could happen if it does? (e.g., overheating, damage)
- What safeguards exist? (e.g., alarms, relief valves)
5. Evaluate risk, make recommendations
Evaluate risk and then make recommendations for improvement if existing protections are not enough.
