From Richard Arthur
Fail-safe technology is an essential goal in all nuclear power generation, and yet it continues to be ignored by an arrogant industry (26 March, p 8).
The question that should be asked is why zirconium is still used in cladding for nuclear fuel rods after being implicated in the Three Mile Island disaster. Zirconium readily generates explosive hydrogen gas if reactor coolant stops circulating. I believe safer substitutes are available but not used because they impair efficiency.
Nuclear power is only as safe as its design, and earthquakes should hardly come as a surprise. A properly designed plant must be self-regulating and not rely on back-up.
Keynsham, Avon, UK
