Bowtie Terminology: 7-must know terms

In the realm of bowtie diagrams, there are key phrases you might come across. This article will explain 7 must-know terms to understand bowtie diagrams better.

1. Risk assessment

In the realm of process safety, a risk assessment is the cornerstone. It's the systematic evaluation of your risk management practices, ensuring alignment with organisational or regulatory standards. By assessing risk, you're actively minimising workplace hazards, an indispensable aspect of overall safety.

Bowtie diagrams are the go-to tool to pull together your assessment in a visual diagram, giving you a big-picture overview of each potential risk.

2. Cumulative risk

Think of cumulative risk as the sum of individual risks, reflecting the overall risk level when multiple scenarios coalesce. Bowtie diagrams emerge as a powerful tool, offering a visual representation of cumulative risk. They allow you to clearly discern the repercussions of one or multiple barrier failures. Zoom out further, and you can analyse data across multiple diagrams through a dashboard, gaining a comprehensive view of your overall risk landscape.

3. Bowtie diagram

Bowtie diagrams are a visual representation of risks and control measures. Think of it as a map that guides you through the hazards and potential harm in your organisation.

At the heart of this diagram is what we call the 'top event,' which is the loss of control of the hazard that has the potential to escalate. If your hazard is operating heavy machinery, the event is the scenario that you really don’t want taking place- like losing control of the machinery.

On the left side, you have the threats, the things that lead to this top event. Why did the operator lose control of the heavy machinery, for example?

And over on the right, you find the consequences of that event taking place. If they lose control of the machinery, it could lead to injury or loss of life...

And what brings your diagram together are the barriers – these are your safety nets, the things you put in place to stop the event from happening. Together, these elements create the shape of a bowtie, hence the name.

4. Metadata

Metadata is the additional layer of information describing various elements, typically barriers. It ensures no detail is overlooked in your risk scenario. Common metadata types include description, condition, type, and owner. You should customise metadata to meet your organisation's specific needs and enhance the depth of your risk analysis.

5. Risk matrix

A risk matrix is the compass guiding risk evaluation and prioritisation. Typically presented as a 5x5 grid, it assesses risks based on the likelihood of occurrence and the severity of outcomes. Placing operations or activities on a risk matrix visually illuminates associated risks, offering a clear understanding of potential hazards.

6. Risk attribute - Residual and initial

A risk attribute is the rating on the risk matrix that you assign to a particular risk.

Risk attributes are divided into two categories: initial and residual. Initial risk is calculated without the consideration of any barriers, or measures you have in place to prevent or mitigate an incident. Residual risk is the risk that remains after you have considered the affect of your barriers. Ask yourself, how much risk is incurred without any safety measures in place? And, how much risk is incurred if these measures are in place and effective?

7. ALARP

ALARP reviews ensure risk is managed to an appropriate level. ALARP, or 'as low as reasonably practicable,' prompts reflection on how far we should go to prevent risk and how to gauge if enough has been done. Bowtie diagrams can offer supportive evidence to answer these critical questions.

Conclusion

So there you have it, 7 key phrases you will most likely hear when it comes to creating a bowtie diagram. Think we missed anything? Let us know at support@bowtiemaster.com.

Watch the video on our Youtube Channel, @salustechnical.