  Idioms are small, reusable Bayesian network (BN) fragments that represent
generic types of uncertain reasoning. This paper shows how idioms can be used
to build causal BNs for product safety and risk assessment that use a
combination of data and knowledge. We show that the specific product safety
idioms that we introduce are sufficient to build full BN models to evaluate
safety and risk for a wide range of products. The resulting models can be used
by safety regulators and product manufacturers even when there are limited (or
no) product testing data.
