Events in Japan are tragic, let's make no mistake about that.  The uncontrolled release of radiation from their nuclear plant is worrying, causing members of the public to have an unchosen risk of short and long term effects of the radiation they receive.  But a bit of perspective please... the NHS is due to give me 50Gy (i.e. 5000 cGy or 50,000mGy) split into 25 'fractions' in a therapeutic role.  Carefully targetted at a small part of my body and 'risk balanced' that it is less likely (or no more likely) to cause than cure cancer... and as the leaflet so casually puts it (paraphrased)... even if it does it won't be for many years anyway.  The bottom line is this: 50Gy is a lot.

There is a massive difference between me choosing to accept the risks posed by my treatment than some innocent Japanese person receiving a whole body dose even at a substantially lower level.  But there is also a lot of sensationalist and ill-conveived reporting going on.

Most people in the UK happily accept X-rays and CT scans, quietly building up their dose uptake (often without knowing it) and remain blissfully ignorant of any link between the diagnostic or therapeutic uses of radiation and the nuclear industry.  Most people who receive radiotherapy will never know how big a dose they get - I know only because I asked.  Sometimes I suspect ignorance is bliss and a little knowledge very dangerous.

After consideration, I have opted not to include any numerical comparative stuff here lest it be misquoted or misappropriated.  Suffice to say that radiotherapy doses, whatever the practitioners say, are big.  They are also carefully targetted and controlled.  I am certainly not concerned - beyond a professional curiosity - about my upcoming treatment, the benefit of which outweighs the risks.  Thus far, the doses to which people in Japan have been exposed seem, thankfully, to substantially lower, albeit that they are whole body and unchosen.

Right now it is clearly evident a little knowledge is misleading and even dangerous... I am glad that as a former nuclear safety assessor I at least understand what is being said and know where to find out accurate information.

(btw UK reactors are deisgned to withstand earthquakes, and tsunamis are considered in developing the safety cases)