NRC SEEKS PUBLIC COMMENT AT START OF PROCESS

TO REVISE “STATION BLACKOUT” RULE

The Nuclear Regulatory Commission is seeking public comment as the agency begins 

considering changes to the “station blackout” (or SBO) rule. The rule requires U.S. commercial 

nuclear power plants to safely deal with the loss of electricity from the transmission grid and 

onsite emergency generators. This rulemaking process comes in response to a recommendation 

for enhancing safety at U.S. reactors based on lessons learned from the accident at Japan’s 

Fukushima Daiichi nuclear power plant.

The NRC’s Advanced Notice of Proposed Rulemaking published today in the Federal 

Register asks for comment on specific questions and issues related to addressing SBO 

conditions. The comments will help develop new SBO requirements and their regulatory basis. 

The notice’s questions include:

• Should SBO equipment be designed to withstand severe natural events the facility is not 

already designed for?

• Should SBO mitigation strategies consider such severe natural events? 

• Should SBO analysis consider a flood greater than the plant is designed for, and if so, 

what criteria should be used to determine that higher flood level?

• How should plant coping times for SBO conditions account for the time to 1) identify and 

determine the need to take mitigative actions and 2) implement SBO strategies under 

worst case conditions? and

• How long should plants expect to rely on mitigation strategies before offsite help arrives?

Public comments should be submitted by May 4; comments received after the deadline 

will be considered if possible, but the NRC is only able to ensure consideration of comments 

received by the deadline. Due to this effort’s priority and the Commission’s associated effort to 

expedite the action, any requests to extend the public comment period must demonstrate

extraordinary circumstances.

All comments should reference Docket ID NRC-2011-0299. Comments can be 

submitted through the regulations.gov website by searching for files under the Docket ID. 

Comments can also be e-mailed to Rulemaking.Comments@nrc.gov; mailed to Secretary, U.S. 

Nuclear Regulatory Commission, ATTN: Rulemakings and Adjudications Staff, Washington, 

DC 20555-0001; or faxed to Secretary, U.S. Nuclear Regulatory Commission at 301-415-1101.

NRC NEWS

U.S. NUCLEAR REGULATORY COMMISSION

Office of Public Affairs Telephone: 301/415-8200

Washington, D.C. 20555-0001

E-mail: opa.resource@nrc.gov Site: www.nrc.gov

Blog: http://public-blog.nrc-gateway.gov

No. 12-028 March 20, 2012
This rulemaking process addresses one of what the NRC determined to be the highestpriority recommendations from the agency’s Japan Near-Term Task Force. The Task Force 

issued its report in July 2011. The NRC staff continues to examine how to best address the 

remaining Task Force recommendations, as well as additional topics raised during the early 

implementation effort. The SBO rulemaking could also encompass a separate petition to consider 

rule revisions to address a blackout triggered by a massive solar flare.

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