The U.S. Nuclear Regulatory Commission (NRC) has issued Revision 1 to its Regulatory Guide 1.191, titled "Fire Protection Program for Nuclear Power Plants During Decommissioning." This updated guide provides new information that has emerged since the original version and includes guidance for plants that have adhered to the National Fire Protection Association's Standard 805 for fire protection. The guide specifies methods the NRC considers acceptable for fire protection in plants that have stopped operating and removed fuel from reactor vessels. Despite issuing this guide, the NRC does not currently plan to enforce its recommendations in a way that changes existing regulations or requirements.
Simple Explanation
The NRC has updated its guide on how to keep old nuclear power plants safe from fires. This new guide has smarter ideas, but the NRC is not forcing anyone to use them right now.