|Fig. 1: A sign commemorates the tragedy of the Three Mile Island incident. (Source: Wikimedia Commons)|
In the apparent rise of nuclear energy, weapons, and technology, there needs to be some sort of governing body to prevent and assess risk. Actions need to be taken in order to mitigate damage, considering the large impact that damage could happen. Simply examining all the nuclear incidents in the past have been enough to warrant a body that oversees all actions. Today, the Nuclear Regulatory Commission regulates all nuclear plants and materials outside of those already under government control.
The need for a governing body began after the devastating Three Mile Island accident. This incident was a partial nuclear meltdown that occurred in 1979 (see Fig. 1), caused by initial mechanical failure. After the incident, the growing concerns about nuclear power became overwhelming, nothing the catastrophical amounts of radioactive elements released into the environment. $1 billion later and years of cleanup eventually helped reduce the collateral damage, but the political influence of nuclear power had already been shaken. Anti-nuclear movements sparked across the country, and ultimately, culminated in the creation of the Nuclear Regulatory Commission (NRC).
Today, the NRC utilizes the Department of Energy's Probabilistic Risk Assessment in order to examine guidelines and prerequisites to building and during inspection. These are outlined by four main components, and include facility structure and operating states, internal events and hazards, external events and hazards, and accident phenomena. All of these four states must be up to a certain standard for the power plant to continue operation. All of these numbers are then calculated into a final judgment to provide insight into the strengths and weaknesses of operation and design of the power plant. 
Once the risk has been established, the NRC uses certain standards to determine whether to continue operation of the plant. Through the International Atomic Energy Agency's Risk Management techniques, the NRC then utilizes strategies inside the guide which often help identify pivotal risks and how to reduce them. All of the potential risks of the power plant are then taken care in order of severity and follow ups are made in order to ensure the risks continue to meet standards. 
The NRC has also established a classification scale to ensure consistency and reliability in emergencies. The lowest level is the unusual event, which means a small problem has occurred. At this level, however, all officials "up to the federal level" are notified but there is no probably release of radioactive material. A regular alert is the next level up, and assumes small emittance. A Site area emergency is the classification of a likely major failure, but waste is not expected to go above levels established by the Environmental Protection Agency. The highest level of alert is the General Emergency, which means there is a serious problem, most likely substantial core damage or reactor fuel melting. This assumes that there is a breach of containment.
After the concerns of nuclear safety and power fully crystallized, the US Government knew they had to take action. They finally established the NRC, which is still active today. While historically it has been seen to be lazy and useless, recent actions taken after the Fukushima incident have proven otherwise.  The NRC continues to be a valuable independent agency with the aim of prioritizing public health and safety with everything related to nuclear energy through risk assessment and management and danger classifications. As the NRC continues to improve their risk assessment standards and qualifications, it will be exciting what new developments await as nuclear energy continues to propel itself into a higher spot of reliance for sustainable, clean energy. 
© Jonathan Mak. The author grants permission to copy, distribute and display this work in unaltered form, with attribution to the author, for noncommercial purposes only. All other rights, including commercial rights, are reserved to the author.
 R. P. Carlisle, "Probabilistic Risk Assessment in Nuclear Reactors: Engineering Success, Public Relations Failure," Technol. Cult. 38, 920 (1997).
 "Risk Management: A Tool for Improving Nuclear Power Plant Performance," International Atomic Energy Agency, IAEA-TECDOC-1209, April 2001.
 R. Stineman, "Nuclear Regulatory Commission," Physics 214, Stanford University, Winter 2015.
 D. Al-Alami, "Nuclear Risk Assessment and Safety," Physics 241, Stanford University, Winter 2015.