High Energy Arcing Fault Events (HEAF) Project
Joint project

The HEAF Project was planned as a three-year programme to be conducted by the United States Nuclear Regulatory Commission (NRC) at a facility in the US. The project's aim was to conduct experiments in order to explore the basic configurations, failure modes and effects of high energy arc faults (HEAF) events. The equipment tested primarily consisted of switchgear and bussing components. Since the switchgear and other equipment necessary for testing was very expensive, the programme relied on signatories' in-kind contributions.

The project had two objectives, which was to

  • draft an international, peer-reviewed guidance document (in the US NRC NUREG series) that could be readily used to assist the regulators of participants
  • draft a joint nuclear safety project report covering all testing and data captured.

A significant amount of full-size equipment had been tested. The initial testing took place in June 2014 in the presence of project members followed by 3 further campaigns in November 2014, March 2015 and October 2015. Data including high-speed high-definition (HD) video had been captured by the US NRC team and was shared amongst other participants in February 2016. Partners then carried out their analyses of the data and contributed to the final report. The first draft of the final report was delivered in June 2016, which necessitated an extension to the project end date to December 2016.

Currently, its present mandate is to perform studies to obtain scientific fire data on high energy arcing fault phenomena known to occur in nuclear power plants through carefully designed experiments:

  • use data from the experiments and past events to develop a mechanistic model to account for the failure modes and consequence portions of HEAFs
  • improve the state of knowledge and provide a better characterisation of HEAFs in fire probabilistic risk assessment (PRA)
  • examine the initial impact of the arc to primary equipment and the subsequent damage created by the initiation of an arc (e.gsecondary fires).

HEAF members' area (password protected | reminder)


Belgium, Canada, France, Germany, Japan, Korea, Netherlands, Spain and United States.

Project period

February 2019-December 2021


EUR 2.38 million