What is the main difference between qualitative and quantitative risk assessment?

The main difference between qualitative and quantitative risk assessments lies in how risks are evaluated and represented. Qualitative risk assessments focus on subjective rankings based on the judgment and experience of the assessors. They analyze risks by using descriptive terms rather than numerical values, which allows for a more flexible approach to understanding potential impacts and probabilities. This method is often useful when data is limited or when issues are complex and do not lend themselves readily to numerical expression.

On the other hand, quantitative risk assessments aim to assign numerical values to the risks involved and often utilize statistical methods to calculate the likelihood of an event occurring and the potential impact in terms of costs or losses. This method relies on hard data and mathematical models to arrive at more objective conclusions about risk.

In this context, describing qualitative risk assessments as based on subjective ranking captures the essence of its process, emphasizing the reliance on personal judgment rather than numerical data, which characterizes quantitative assessments.