Eric McErlain, editor of the weblog NEI Nuclear Notes, sends me a link to the Nuclear Energy Institute's summary of safety measures in U.S. nuclear power plants. Here's an abridged version of their list:
Comprehensive nuclear safety process. Safety is ensured at nuclear power plants in the United States according to four interlocking steps:
1. extensive government regulations have been established to protect the public,
2. nuclear plants are built according to designs that meet the regulations,
3. owners are required to operate the plants according to approved specifications and abide by strict controls on changing the designs, and 4. regulators monitor operations and compliance with regulations through resident inspectors stationed at every site.Multiple redundant safety systems... Two or more safety systems perform key functions independently, such that, if one fails, there is always another to back it up, providing continuous protection.
Highly reliable automated safety systems. A nuclear plant has numerous built-in sensors to watch temperature, pressure, water level, and other indicators important to safety. The sensors are connected to control and protection systems that adjust or shut down the plant, immediately and automatically, when pre-set safety parameters are approached or breached.
Physical barriers safely contain radiation and provide emergency protection... The containment ensures that the Chernobyl accident of 1986 a substantial radiation leak could not occur in the United States...
Multiple controls on the chain reaction. Control rods present in the reactor are adjusted to regulate the reaction by absorbing neutrons. In addition, the water level inside the reactor also moderates the reaction. Water ordinarily facilitates the reaction, but the greater the reaction and the greater the heat produced, the more water is turned to steam, leaving less to promote the reaction. In this way, the reaction is automatically moderated. Moreover, if the water were ever lost, multiple emergency cooling systems would activate to make up the water loss and keep the reactor from overheating....
Materials management for reliable plant components.All nuclear plant owners participate in a comprehensive, industry-wide materials management program that identifies when components of nuclear plants need to be inspected, repaired, and replaced to ensure that the materials from which they are made perform according to standards..
Plant fire protection receives special focus...
Plant security protects against sabotage. Plant security resources and procedures are designed to prevent a hypothetical intrusion involving a paramilitary force armed with automatic weapons and explosives. Security measures include physical barriers and illuminated isolation zones; well-trained and well-equipped guards; surveillance and patrols of the perimeter fence; search of all entering vehicles and persons; intrusion detection aids, such as closed-circuit television and alarm devices; bullet-resisting barriers to critical areas; a contingency reaction force; coordinated emergency plans with off-site police, fire, and emergency management organizations; and regular drills and periodic procedural reviews. Employees undergo a variety of tests and record checks before obtaining various levels of security clearance, which is controlled by electronic key cards. Employees with unescorted access are subject to continual behavioral observation programs.
It all makes a lot of sense to me. Skeptics, however, might note that the Institute is not an impartial party, so comments or a heads-up on more critical assessments, always welcome, are especially encouraged in this case.