Probability of failure types
A probability of failure (PoF) type is one method of determining the probability that an asset failure will occur. The PoF measures the number of times an asset is expected to fail within one year. For example, a PoF of 1 indicates that the asset is certain to fail, while a PoF of 0.15 indicates that there is a 15% chance the asset will fail. The PoF can even be greater than 1 if an asset is likely to fail more than once per year.
You can define multiple PoF types, because the odds of different types of failures may be calculated in different ways. For example, the probability that a vehicle will break down depends on factors such as its mileage and its maintenance history, so the PoF type for this event will typically use a formula. On the other hand, the probability of an earthquake doesn't depend on the characteristics of a particular asset, so the PoF type for an earthquake might use a list of ratings rather than a formula. You can then select the appropriate rating when you use the PoF type to create a risk event type.