The scenario describes risk aggregation, which is the process of combining multiple individual risks or losses to understand the total, consolidated impact of an event or a set of circumstances. In this case, the numerous injury claims and the loss of revenue are distinct financial consequences stemming from the single event of the train crash. By considering them together, the train operator is aggregating these losses to determine the overall financial and operational impact, which is a core concept in risk analysis.

B. risk categorisation: This is the process of grouping risks based on their source or nature (e.g., financial, operational, strategic), not summing the consequences of an event that has already occurred.

C. risk probability: This refers to the likelihood of an event happening. The train crash has already occurred, so the focus is on its consequences, not its probability.

D. risk severity: This describes the magnitude of the impact of a risk. While the situation is severe, "aggregation" specifically refers to the act of combining multiple distinct losses.

1. ISO Guide 73:2009, Risk management — Vocabulary.

Reference: Definition 3.8.1.6.

Content: Defines "risk aggregation" as the "combination of a number of risks into a single risk." The scenario perfectly illustrates this by combining the numerous claims (a number of risks/losses) and the revenue loss into a single, overall impact of the crash.

2. Purdy, G. (2010). ISO 31000:2009—Setting a New Standard for Risk Management. Risk Analysis: An International Journal, 30(6), 881-886.

Reference: Page 884, Section on "The Risk Management Process."

Content: The article discusses the ISO 31000 risk management process, which includes risk analysis. A key part of analysis is understanding the full scope of consequences. Aggregating various impacts (like injury claims and revenue loss) is essential to properly analyze the magnitude of the risk and inform the risk evaluation step, aligning with the principles of a comprehensive approach advocated by the standard. DOI: https://doi.org/10.1111/j.1539-6924.2010.01442.x

3. Leitch, M. (2010). ISO 31000:2009 - The new international standard on risk management. Risk Management, 12(4), 162-181.

Reference: Page 174.

Content: The paper explains that understanding the "causes and sources of risk, their positive and negative consequences, and the likelihood that those consequences can occur" is central to risk analysis under ISO 31000. Aggregating the various negative consequences from a single event is a practical application of this principle to determine the overall level of risk.