Core damage frequency is the headline result of a Level 1 probabilistic safety assessment, summing the frequencies of all modelled sequences that lead to core damage, expressed per reactor-year. Common safety targets are below about 1 in 10,000 per reactor-year for existing plants and 1 in 100,000 for new designs. Changes in CDF and in large early release frequency are used to judge proposed plant changes.
Mod drops CDF from 3E-5 to 2E-5 per reactor-year, mostly by fixing the fire scenario in the cable room.
Also heard as
- core damage frequency
Related terms
PSA
Probabilistic safety assessment: a systematic model of how accidents could happen and how likely each outcome is.
Severe accident
An accident involving significant damage to the reactor core, with possible fuel melting and large releases.
Source term
The amount, type, timing and chemical form of radioactive material released, or assumed released, in an accident.
Beyond design basis accident
An accident more severe than those the plant's safety systems were explicitly designed to handle.