Don’t say “Don’t panic” because People Will Panic
BOILING WATER REACTOR SYSTEM: The system’s inverted lightbulb primary containment vents below through pipes to a pressure suppression torus. Once that torus breaches due to overpressure, the secondary containment is all that separates the released radioactive steam from the outside environment.
Image: http://www.nucleartourist.com/
Nuclear Experts Explain Worst-Case Scenario at Fukushima Power Plant
The type of accident occurring now in Japan derives from a loss of offsite AC power and then a subsequent failure of emergency power on site. Engineers there are racing to restore AC power to prevent a core meltdown.
By Steve Mirsky
Read the article in Scientific American.