United States Nuclear Regulatory Commission - Protecting People and the Environment

What's New in the 2015 Update

Changes to Web Site Content

This is the first year for a new trend update frequency. The schedule for performing component and system study updates is now every other year. The next update of these studies will be based on the 2016 calendar year. The loss of offsite power and initiating event updates are still done each year.

The parameters used in the SPAR models have been updated using data through calendar year 2015. This includes initiating event frequencies, component unreliabilities, component unavailabilities, common cause failure alpha factors, and loss of offsite power nonrecovery probabilities.

Historical Update Summaries

Page Last Reviewed/Updated Monday, March 27, 2017