Nuclear Disaster

The Japanese earthquake, Tsunami and subsequent problems at one of their nuclear power stations have been world news for a week now and we must all have great sympathy for the Japanese people.
However, in this country, I have noticed that the anti-nuclear power contingent are already using the disaster at the power station to press their case against nuclear power generation, without, of course, offering any alternative.
Personally, I would prefer to wait until we see the final outcome before jumping to any rash conclusions. Most importantly, we need to know how many people have been killed by the accident (as distinct from the earthquake & tsunami), together with an assessment of the numbers who are likely to suffer from the effects of radiation either now, or later in their lives. In this respect, at the time of Chernobyl, the predictions ranged from tens to hundreds of thousands, which has since been proven to be more like hundreds rather than thousands.

But as a retired engineer (albeit in a different field) I would like to make a few points which have applied to all engineering activities over the last few hundred years.
The first thing to note is that the initial engineering in most areas was usually very crude when compared with later developments, but was always inspired by a desire to do something better or more efficiently than the existing method.
Thus bridges were built of cast iron and later steel, rather than wood, because they could have longer spans and take larger loads; Steam engines started to be used instead of horses, because they had more power and became cheaper to run; aeroplanes took over from trains and ships because people wanted to get to their destination quicker; the list is endless.
However, it is important to note that none of these developments were without risk, and that there were a large number of accidents and disasters along the way before they reached their present state of development. I honestly believe that engineering is one of the few activities where those responsible can genuinely claim to have learnt from their mistakes, unlike many other areas where "We will learn from our mistakes" is merely a catchphrase.

Steam Engines and the early railways probably caused the highest number of deaths over the years, and although unfortunately accidents still happen, their frequency and severity has been considerably reduced.The deaths certainly did not stop the development of the railways, but invariably led to improvements following an enquiry into the causes.
Shipping has had its fair share of disasters; whether you regard the wrecking of the British naval fleet on the Scillies as an engineering disaster is a moot point, but the solution certainly was in the form of Harrison's chronometer.
Bridges too, have not been immune. The most famous is the collapse of the Tay Bridge disaster of 1879 when 75 people were killed following the collapse of the bridge whilst a train was crossing. However it didn't stop a new bridge being build in 1887 which is still in use today, having had its only major maintenance in 2007, 130 years later!
Air accidents, of course always hit the headlines, but the two Comet disasters didn't stop the construction of jet aircraft, nor indeed have recent accidents stopped people still wanting to fly.

I make these points at some length because nothing that man does in this world is 100% safe, and engineering is no exception. But as I said above, engineers always learn from accidents, which frequently occur due to factors of which they were either unaware or for which they made insufficient allowances. This will be true of what happened in Japan, and strictly from an engineering standpoint, one could say that this disaster has stress tested the reactors to a level that they would never have received otherwise. To a non-specialist like myself, it would seem that the actual reactor design was adequate but that it was the cooling system, or its power supplies which failed and that their design clearly will need re-appraisal in any new construction.

That, of course, is my initial reaction without real facts; I would much prefer that all the so-called experts desisted from making comments until the full effects are known and an enquiry by genuine experts has reached its conclusions.