Safe Speed Forums

Respect please for the 200 unbelievably brave nuclear power station workers who are trying to prevent a catastrophe in Japan. It already appears that many will die from radiation poisoning.

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nigel_bytes

Do you have a source for that information?

I was aware that some had been killed in the blast caused by hydrogen gas igniting, but not figures for projected radiation linked deaths.

I agree that they are dedicated to the job they undertook to do - as happened at Chernobyl, and at Windscale.

It seems that selfless acts abound in these situations.

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Time to take responsibility for our actions.. and don't be afraid of speaking out!

For some technical background information, this is a fascinating article which hopefully will continue to be updated...

The Hiroshima Syndrome - Fukushima Accident

mb

Yes!

But I would say for ALL the people of Japan actually.

We could, and should, learn much from their incredible and stoic example.

Especially the respect and esteem they have for their elders...!!!

I would gladly welcome any of them into my home, more so than many British people, if I could help...

A terrible and heart-breaking situation and tragedy if ever there was.

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The views expressed in this post are personal opinions and do not necessarily represent the views of Safe Speed.
You will be branded a threat to society by going over a speed limit where it is safe to do so, and suffer the consequences of your actions in a way criminals do not, more so than someone who is a real threat to our society.

Except for the f**k-wits who designed the inadequate emergency cooling system for the reactors.

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When I see an adult on a bicycle, I do not despair for the future of the human race. H.G. Wells
When I see a youth in a motor car I do d.c.brown

To be fair, those designing the cooling system would have been given a design brief, which failed to anticipate the size of the tsunami, which swamped the electrical supply, AND the back up generators.

Given the information they had to work on, this is perhaps easier to criticise in hind sight than before the event, and it will lead to a tightening up of standards world wide.

If I remember correctly, aircraft manufacturers using "fly by wire" technology use five time redundancy as a minimum standard - in other words systems have 4 back up stages.
Here they only had two - battery and diesel generators.

What seems to have impressed industry experts, is that the reactor core vessels withstood the actual quake which was so much more severe than anything anticipated.
Despite this, some cretins were questioning whether Britain's nuclear reactors were sufficiently safe, given the (paltry) quakes we have suffered recently!

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Time to take responsibility for our actions.. and don't be afraid of speaking out!

It was the people who wrote that design brief whom I was criticising. I suspect that the deficiencies will turn out to be down to saving cost..


I can't accept that. These events were neither unprecedented nor surprising. Given the geology of the Japanese islands this earthquake was going to happen sooner or later. The containment building and reactor vessels stood the shock very well which puts the failure of the cooling systems into stark relief. The lack of intrinsic cooling in BWRs has been a cause of concern since the early days of the industry but the experts have always reassured us that multiple redundancy ensured their safety. That is clearly untrue in this case


There are other things than earthquakes which can damage a power station - aircraft strike or terrorism for example. So if this incident forces a more critical review of safety systems in the world's reactors it will be no bad thing. I fear that the public reaction will set back the development of nuclear power by a generation

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When I see an adult on a bicycle, I do not despair for the future of the human race. H.G. Wells
When I see a youth in a motor car I do d.c.brown

So, the cooling systems were powered by grid electricity (presumably generated by other power stations), backed up by UPS battery systems and then generators.

What further redundancy could you have built into the system which would have survived this catastrophe?

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Malcolm W.
The views expressed in this post are personal opinions and do not represent the views of Safespeed.

The plant will have been designed with an extreme earthquake and tsunami event in mind.

IIRC it would generally be something like the 100 year event (i.e. that would normally be expected to occur once every century on average. I would imagine that this would be increased for a nuclear plant.

But a Mag 9.0 earthquake and a tsunami that big (which is waht caused the problem) may have been bigger than the design extreme events.

So not so much a fault of the designers, but the codes of practice.

I'm just surprised that the stations weren't built further inland where the Tsunami's effect would have been so much less severe. It's more expensive to send the energy to the coast but it would surely have been worth it.

I am also surprised that the buildings were not designed with a more 'water' dynamic area, like having houses built with the corner facing the coast.

I'm probably missing something obvious..

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The views expressed in this post are personal opinions and do not necessarily represent the views of Safe Speed.
You will be branded a threat to society by going over a speed limit where it is safe to do so, and suffer the consequences of your actions in a way criminals do not, more so than someone who is a real threat to our society.

Probably the fact that these reactors were built over 40 years ago and the same design would not be used now.

AIUI the reactor housings survived the earthquake and the problem was caused by the tsunami knocking out the backup power systems. I read that this earthquake was the sixth biggest ever recorded.

Many of our nuclear power stations like Hinkley Point are built close to the sea, of course.

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"Show me someone who says that they have never exceeded a speed limit, and I'll show you a liar, or a menace." (Austin Williams - Director, Transport Research Group)

Any views expressed in this post are personal opinions and may not represent the views of Safe Speed

All power stations require water in fairly large quantities, and the sea is a convenient place to dispose of the cooling water.

All the infrastructure in Japan seems to have survived the ground displacement of the earthquake - it was the size of the tsunami which they were unprepared for.

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Time to take responsibility for our actions.. and don't be afraid of speaking out!

My 2p:

This outcome may have been a case of convenient economics.
I’m sure the engineers could have reinforced the structure to withstand this magnitude of event and greater still, but doing so costs so much more, possibly negating the viability of the project. Budgets aren’t unlimited, so the line has to be drawn somewhere.

The original design managers could well have concluded there is little point in investing so much into something for a statistically unlikely event, in what could have been a shorter lifetime of the station (these things have a habit of being used beyond their designed lifetime). All considered, it may yet end up being cheaper to clean up today’s mess (there are other stations to provide power), instead of investing the necessary amount 40 years ago (as well as delaying the project, which itself costs money).

I’m not defending whatever decisions were made; I’m merely suggesting these risks could have already been sufficiently considered and could be deemed (or spun) as appropriate, even with hindsight.

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Views expressed are personal opinions and are not necessarily shared by the Safe Speed campaign

The backup power system - the generators - should have been designed to stand inundation by water. Portable generators should have been stored in a higher location with helicopters to fly them in. They should have had ample reserves of fuel for auxiliary pumps (they actually ran out of fuel whilst pumping sea water into the reactors.

But if you are correct and the system in place was the best that could be achieved then BWRs should never have been built in the first place.

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When I see an adult on a bicycle, I do not despair for the future of the human race. H.G. Wells
When I see a youth in a motor car I do d.c.brown

There was a discussion about this on Material World on R4 which described it as an amazing series of unfortunate errors, i.e. systems failing because of the tsunami, then the back-up's failing because of the earthquake. IIRC the conclusion was that while the tsunami was chiefly to blame, the plant could have surbvived either the mag 9.0 earthquake, or the mahoosive tsunami, but not both.

You might imagine that the Japanese would be very conservative in their assessment of risks when it comes to atomic radiation.

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Malcolm W.
The views expressed in this post are personal opinions and do not represent the views of Safespeed.

This might be of interest....

http://www.theregister.co.uk/2011/03/18 ... ma_friday/

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"The road to a police state is paved with public safety legislation"

On a lighter note...

http://images2.wikia.nocookie.net/__cb2 ... ar-doh.jpg

I do love dark humour

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"The road to a police state is paved with public safety legislation"

The emergency pumps were under 30 feet of tsunami that had flattened everything in it's path. Yes, maybe now with the benefit of hindsight they could have had some pumps stashed away on higher ground up a mountain. But what happens if there is an earthquake, tsunami AND a volcano erupts?

They knew what they knew, knew what they didn't know, but didn't know what they didn't know.

The job right now, is to get the situation under control. Then when it is they can start learning from this. I understand the plant is 40 years old and due to be de-commissioned anyway.

Were they?

I may well have missed something (And will stand to be corrected if I have) but...

The reports I have read simply state that the back up generators "Stopped" an hour or so after the initial earthquacke triggered the reactor shutdown! I have not seen a specific explanation as to WHY they stopped! it just seems to be assumed that they were stopped by flooding (Though why they could not be restarted I do not know-though I have a theory)

Sadly my own experiance of back up generators is that they tend to be ignored until they are really needed! If I was looking to place a small bet I would sugest that the problem is likly to have been contaminated fuel and that the contamination prexisted the tsunami!

Of course only time will tell...

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"The road to a police state is paved with public safety legislation"