What does the probability of occurrence multiplied by the impact of the event, equals to

The formula Probability of occurrence × Impact of the event is a common technique in quantitative or semi-quantitative risk analysis. The product of these two variables yields a numerical value or score. This value represents the significance, size, or severity of the risk, which is most precisely termed its magnitude.

While the term "level of risk" is also correct in a broader sense, "magnitude" specifically refers to the calculated value itself. The ISO 31000:2018 standard defines "level of risk" as the "magnitude of a risk... expressed in terms of the combination of consequences and their likelihood." This indicates that the calculation directly determines the magnitude.

A. Risk Tangent: This is not a recognized term within the ISO 31000 framework or standard risk management vocabulary. It appears to be a distractor option combining mathematical and risk terminology incorrectly.

B. Risk Scale: A risk scale is the measurement system used to rate the inputs (i.e., probability and impact), for example, on a scale of 1 to 5. It is the tool for measurement, not the result of the calculation.

C. Risk Level: Although closely related and often used synonymously with magnitude, "level" can also refer to the qualitative band (e.g., 'High', 'Medium', 'Low') into which the calculated magnitude falls. "Magnitude" is the more precise term for the specific numerical output of the formula.

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1. ISO 31000:2018 - Risk management — Guidelines

Clause 3.8: The standard defines "level of risk" as the "magnitude of a risk or combination of risks

expressed in terms of the combination of consequences and their likelihood." This directly links the calculation (combination) to the concept of magnitude.

2. ISO Guide 73:2009 - Risk management — Vocabulary

Definition 3.6.1.8: This guide

which provides the foundational vocabulary for ISO 31000

offers the same definition: "level of risk: magnitude of a risk... expressed in terms of the combination of consequences... and their likelihood." The calculation's result is the expression of this magnitude.

3. Purdy

G. (2010). ISO 31000:2009—Setting a new standard for risk management. Risk Analysis: An International Journal

30(6)

881-886. In section 4

the paper notes

"The level of risk (sometimes called risk magnitude) is determined by a combination of the consequences of an event and the associated likelihood of occurrence." This highlights the interchangeability but also the distinction

where magnitude is the core component. DOI: https://doi.org/10.1111/j.1539-6924.2010.01442.x

4. Aven

T. (2016). Risk assessment and risk management: Review of recent advances on their foundation. European Journal of Operational Research

253(1)

1-13. This paper discusses various risk metrics

referring to the product of probability and consequence as a simplified measure used to represent the magnitude of a risk for comparison and ranking purposes. DOI: https://doi.org/10.1016/j.ejor.2015.12.023