|An incipient fire detection system at Harris.|
Over the course of several decades, the nuclear industry and NRC have worked together to continuously improve fire safety at the nation’s nuclear reactors. By constantly examining relevant operating experience, we have been able to take on plant upgrades and make improvements to plant programs to reduce the probability and consequences of potential fire events. One major effort in this area has involved National Fire Protection Association Standard 805, "Performance-Based Standard for Fire Protection for Light-Water Reactor Electric Generating Plants” (NFPA 805).
This standard provides one approach to implementing fire protection at nuclear reactors, and while adoption of the standard is voluntary, roughly a third of the nuclear power plants in the U.S., including several Exelon plants, are in the process of implementing this standard. The standard provides the same level of protection against fire events as does the traditional fire protection program outlined in the NRC’s regulations. NFPA 805 additionally allows licensees to use Probabilistic Risk Assessments (PRAs) to identify the most beneficial actions and plant modifications to enhancing plant safety based on in-depth safety analysis of the plant.
The licensees transitioning to NFPA 805 have conducted substantial analysis of their plants, and have used this analysis to assist in developing improvements to fire safety. These improvements include physical plant modifications, as well as changes to plant programs to more completely integrate the findings of plant safety analyses.
For example, the Harris Nuclear Plant installed specialized systems that are capable of detecting precursors to fires in areas of the plant where preventing a fire provides a substantial improvement to plant safety. These systems, known as incipient fire detection systems, have been able to detect potential fire events so early on that plant personnel can take action to prevent damage to safety equipment.
The safety enhancements are not limited to additional plant equipment; the monitoring programs that NFPA 805 calls for support plants using the data received from these monitoring programs to identify better practices for fire-related surveillances and plant procedures. This continuous feedback in the performance-based program supported by NFPA 805 helps plants improve safety on a daily basis.
All plants will benefit from these improvements, as the lessons learned from these programs help us improve operations and enhance fire safety across the nuclear fleet. The insights from our safety analyses are helping us all continuously improve fire safety throughout the fleet.