hbrobinson


Benny Hill Explains the NRC Approach to Nuclear Safety

, former director, Nuclear Safety Project

The Nuclear Regulatory Commission’s safety regulations require that nuclear reactors be designed to protect the public from postulated accidents, such as the rupture of pipes that would limit the flow of cooling water to the reactor. These regulations include General Design Criteria 34 and 35 in Appendix A to 10 CFR Part 50.

Emergency diesel generators (EDGs) are important safety systems since they provide electricity to emergency equipment if outside power is cut off to the plant—another postulated accident. This electricity, for example, would allow pumps to continue to send cooling water to the reactor vessel to prevent overheating damage to the core. So the NRC has requirements that limit how long a reactor can continue operating without one of its two EDGs under different conditions. The shortest period is 3 days while the longest period is 14 days. Read more >

Bookmark and Share

Ad Hoc Fire Protection at Nuclear Plants Not Good Enough

, former director, Nuclear Safety Project

A fire at a nuclear reactor is serious business. There are many ways to trigger a nuclear accident leading to damage of the reactor core, which can result in the release of radiation. But according to a senior manager at the US Nuclear Regulatory Commission (NRC), for a typical nuclear reactor, roughly half the risk that the reactor core will be damaged is due to the risk of fire. In other words, the odds that a fire will cause an accident leading to core damage equals that from all other causes combined. And that risk estimate assumes the fire protection regulations are being met. Read more >

Bookmark and Share

Friendly Answers Following Blowing of the Winds

, former director, Nuclear Safety Project

Disaster by Design/ Safety by Intent #59

Safety by Intent

With ample warning, Hurricane Matthew made landfall in South Carolina coast on October 8, 2016, bringing along its heavy rainfall and high winds.

The Federal Emergency Management Agency conducted Disaster Initiated Reviews for nuclear plants in South Carolina, North Carolina and Florida to determine whether Hurricane Matthew adversely affected emergency planning measures within a 10-mile radius of each site. Read more >

Bookmark and Share

Nuclear Plant Emergency Preparedness – Southern Exposure 2015

, former director, Nuclear Safety Project

Disaster by Design/ Safety by Intent #37

Disaster by Design

Disaster by Design/Safety by Intent #35 described some of the limitations in the emergency exercises conducted at least once every two years for U.S. nuclear power plants. The exercises are scheduled months in advance and last but a handful of hours. Real nuclear plant accidents are never scheduled in advance and take weeks to stabilize and years to recover. The value of the biennial exercises is diminished by these constraints. Read more >

Bookmark and Share

Nuclear Plant Emergency Preparedness (or Pretending)

, former director, Nuclear Safety Project

Disaster by Design/ Safety by Intent #35

Disaster by Design

Fission Stories #58 described how control room operators prepared for a test to be conducted on the Unit 2 reactor at the Millstone nuclear plant in Connecticut. Each operator who would touch control switches during the test was assigned a peer checker who would have a copy of the test procedure in hand to verify that the operator conducted every step as specified. The entire group of operators and peer checkers went into the simulator—a full-scale, computer-controlled mockup of the control room—two days before the test to rehearse it a few times. What could go wrong? Read more >

Bookmark and Share