by Dr David Lowry
(first published in The Oxford Biographical Dictionary)
Thomas Tuohy, (1917-2008), chemical engineer and nuclear plant manager industry executive, was born in Simpson’s Hotel, Wallesend, Northumberland Newcastle-upon-Tyne, on 7 November 1917, the elder son of to Michael Tuohy, a former radio engineer private in the Irish Guards ( and later a hotelier who was then the manager of the hotel -in reality a lodging house catering mainly for homeless men), and later a radio engineer, who hailed from Cobh, Eire and his wife, Isabella Chessels, née Robertson . His father, hailed from Cobh, Ireland; his mother was born in North Shields), of Scottish stock. His brother Peter was born in 1918.
Tuohy was educated at St Cuthbert’s Grammar School, Newcastle, and was awarded a BSc in chemistry from Reading University. During the Second World War, he worked as a chemist in various Royal Ordnance factories.
Tuohy was married three times: first, on 1 June 1940, (Evelyn) to Una Crosthwaite Goodacre (b. 1916/17), a bank clerk, in 1940and daughter of Ralph William Goodacre, a captain in the merchant navy., which produced. They had two sons, Michael (b. 1942) and Philip (b. 1946). The (marriage was dissolved in or before 1949, and on 27 August that year Tuohy married, secondly,); Lilian May Barnes (1924-1971), a laundry charge hand, in 1949,and daughter of Thomas James Barnes, stone quarryman. with whom he They had a son and daughter, Kathleen (b. 1950), and a son, Thomas (b. 1951).
(died 1971) and Shirley de Bernardo, a retired computer systems specialist, hailing from California, in 2004. His children (names U) and his first wife survived him.
Tuohy began work in the immediate post war atomic industry, initially (from 1946) as a health physics manager at Springfields nuclear fuel production plant, in Lancashire (to which he returned briefly as Works manager in 1952-54) then, in 1949, joining Windscale (now Sellafield) as a health physics manager for the plutonium production plant. Subsequently he became manager at the plutonium ‘piles’ and metal production plant, 1950-52, and Windscale deputy works manager, 1954-57.
Tuohy’s claim to fame was his bravery in dousing an out-of-control nuclear conflagration at the plutonium production Windscale ‘piles’ at Sellafield, in October 1957, thus avoiding a nuclear nightmare for the nation.
Seven years earlier, Tuohy had
Seven years earlier, Tuohy had
In 1950 he demonstrated his hands-on approach to solving nuclear problems. During the commissioning of the plutonium production piles, it became apparent that the ‘reactivity’ of Pile 1 could be improved by reducing the amount of neutron-absorbing material in the core. The Windscale managerial boffinsmanagement decided that this could be best done by trimming metal from the fins of the fuel cartridges, but the pressing timetable did not allow them to be shipped back to the cartridge workshop at the fuel production site, at Springfields.
The UK Atomic Energy Authority (UKAEA)’s official historian, Lorna Arnold, later in her seminal account of the accident, ‘Windscale 1957’, recorded: “‘They were dealt with on the spot. Tom Tuohy, deputy works general manager, at Windscale, worked at the charge hoist [(a large mobile platform at the front of the pile]) where, by hand, they cut a strip one-sixteenth of an inch wide from each fin. A million fins were clipped in three weeks during August and September 1950.”’ (Arnold,1992).
Two years later, on 28 March 1952, it was Tuohy who opened the reaction vessel in the chemical separation plant at Sellafield, and handled the first piece of plutonium made in Britain, which was destined for use in the first British nuclear warhead test, off Australia’s north- west coast, in October that year.
Tuohy’s claim to fame was his bravery in dousing an out-of-control nuclear conflagration at the plutonium production Windscale ‘piles’, in October 1957, thus avoiding a nuclear disaster. When the now infamous fire was discovered, Tuohy was at home on leave, looking after his family who all had flu, and had to be specially summoned on site. Several methods were tried to contain the fire: the use of large bellows only served to fan the flames, the attempts at bludgeoning of the 11 eleven tons of burning fuel cartridges through the reactor and into the cooling pond behind it with scaffolding poles proved totally ineffective (“‘they jammed solid”’, Tuohy, in a compelling account, revealed to the subsequent Board of Enquiry, that sat later that month, chaired by Sir William, later Lord, Penny, head of atomic weapons research),
(Windscale Fire Board of Enquiry Transcript, revised version, 1989, 1.14-15)
as did use of liquefied carbon-dioxide from the neighbouring Calder Hall reactor, then also managed by Tuohy.
Tuohy donned full protective equipment and breathing apparatus and scaled the 80 eighty feet to the top of the ‘pile’ reactor building, where he reported no flames, only a dull red luminescence. It was decided, early on the Friday morning of Friday 10 October, as a last resort to use water. This option was very risky, as molten metal oxidises in contact with water, stripping oxygen from the water molecules and leaving free hydrogen, which could mix with incoming air and cause an explosion. Tuohy told Penney’s the subsequent inquiry: “‘We were quite honestly frightened of the water because we didn’t know whether there would be an explosion or not.”’ (Windscale Fire Board of Enquiry Transcript, 1.14-15). But there was no other choice left, so Tuohy took full charge of operations.
(Windscale Fire Board of Enquiry Transcript, revised version, 1989, 1.14-15)
(Windscale Fire Board of Enquiry Transcript, revised version, 1989, 1.14-15)
He reported that both yellow and blue flames could now be seen, indicating what was burning inside the inferno. The makeshift hoses delivered water into the reactor for fully thirty hours, before being turned -off. Tuohy recalled, "‘I went up to check several times until I was satisfied that the fire was out. I did stand to one side, sort of hopefully, but if you're staring straight at the core of a shut down reactor you're going to get quite a bit of radiation."’ (Daily Telegraph, 26 March 2008).
Lord Sir William Penney’s Board of Enquiry report into the 1957 near- disaster concluded that the steps taken to deal with the accident were "‘prompt and efficient and displayed considerable devotion to duty on the part of all concerned"’, but it also admitted in respect of the deleterious health implications that, “‘It appears to us unsatisfactory that tolerance levels in respect of several of the possible hazards should have had to be worked out in haste after the accident had happened.”’ . It was since calculated that at least 240 people will have contracted life-shortening cancers as a result of the atmospheric radioactive releases.
For a month afterwards millions of gallons of milk from the nearby countryside was destroyed, being poured, after dilution, down the drains flowing into the Irish Sea. But for Tuohy’s actions, the radiological consequences could have been very much worse in economic, environmental, and human health costs.
The British Government under Macmillan, then in delicate diplomatic negotiations with Washington over Anglo-American military nuclear collaboration, covered up the causes of the fire, with UK atomic officials allowing the Americans to think that Tuohy’s staff were to blame, to which Tuohy is reported to have responded: “‘I thought they [(the officials]) were a shower of bastards.”’ (Daily Telegraph, Obit. 26 March 2008 http://www.telegraph.co.uk/news/obituaries/1582801/Tom-Tuohy.html)
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www.telegraph.co.uk
Tom Tuohy, who died on March 12 aged 90, played a key role in preventing Britain's worst nuclear disaster in 1957 when he worked out how to put out a major ...
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"‘Mankind had never faced a situation like this; there's no-one to give you any advice,"’, Tuohy later said.
(‘Windscale: a nuclear disaster’, BBC, 5 October 2007).. http://news.bbc.co.uk/1/hi/sci/tech/7030281.stm
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news.bbc.co.uk
Fifty years ago, on the night of 10 October 1957, Britain was on the brink of an unprecedented nuclear tragedy. A fire ripped through the radioactive materials in the ...
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Tuohy was promoted following the fire to become Windscale general manager (1958-64), than managing director of the, UKAEA Production Group (1964-71). He became the first managing director (production) of British Nuclear Fuels Ltd in (BNFL),1971-73, when it was spun out of the UKAEA, and then managing director of the new uranium enrichment company, Urenco, a tripartite venture with the Netherlands and West Germany, from 1973 to 1974.
He was awarded appointed CBE in 1969. However, he never received any formal recognition of his hurculean efforts to control the Windscale fire. Reportedly disillusioned with the way the nuclear business was progressing, he resigned and took early retirement in October 1974, aged only 54. He thereafter lived in Beckermet, near Sellafield, Cumbria, for many years. His second wife having died more than thirty years earlier, on 1 October 2004 he married, thirdly, Shirley Anne de Bernardo, formerly Glinski, a 66-year-old retired computer systems specialist, originally from California, daughter of John de Bernardo, finance director., before emigrating They moved to Australia for the last few years of his life, and Tuohy died in Newcastle, New South Wales, Australia, on 12 March 2008, aged 90.
Sources
Paul Dwyer, Windscale: a nuclear disaster. BBC News Channel, 5 October 2007
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news.bbc.co.uk
Fifty years ago, on the night of 10 October 1957, Britain was on the brink of an unprecedented nuclear tragedy. A fire ripped through the radioactive materials in the ...
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‘A Revised Transcript of the Proceedings of the Board of Enquiry into the Fire at Windscale Pile No.1 October 1957’,
news.bbc.co.uk
Created Date: 7/19/2007 5:49:10 PM
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Lorna Arnold, Windscale 1957: Anatomy of a Nuclear Accident, (Second Edition, (1995)
Paul Dwyer, ‘Windscale: a nuclear disaster’, BBC News Channel, 5 October 2007, _ http://news.bbc.co.uk/1/hi/sci/tech/7030281.stm
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news.bbc.co.uk
Fifty years ago, on the night of 10 October 1957, Britain was on the brink of an unprecedented nuclear tragedy. A fire ripped through the radioactive materials in the ...
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Daily Telegraph (26 March 2008)
Independent (26 March 2008)
Times (15 April 2008)
Guardian (7 May 2008)
Backstory
Windscale's terrible legacy
In the last of his series on the state of Britain's nuclear industry, Paul Brown reports on the site in Cumbria of a notorious accident
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www.theguardian.com
When the Windscale fire was put out in 1957, the melted nuclear fuel and the contaminated surroundings had to be sealed up and guarded - it was feared even a minor ...
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Guardian, Thursday 26 August 1999
When the Windscale fire was put out in 1957, the melted nuclear fuel and the contaminated surroundings had to be sealed up and guarded - it was feared even a minor earth tremor could set off another fire.
It was the world's worst nuclear disaster prior to Chernobyl. A small band of courageous people, some of whom later contracted cancer, fought to prevent the fire getting out of control.
For 40 years, at the heart of Britain's biggest nuclear complex - now called Sellafield - this silent monument to the arms race has remained as a constant threat. The industry was forced to wait until the technology to deal with it was developed.
A necessary breakthrough was a swimming robot able to operate in the dark to locate and pick up nuggets of plutonium contaminated fuel and carry them to submerged skips. This fuel needed to be hauled to safety on an underwater railway, and then, without ever being exposed to air, dismantled and dissolved in acid.
That, according to site manager, Barry Hickey, was the easy bit. The more difficult task is yet to come. It means opening up the Windscale pile, a brick tower, and getting out the melted interior. The plan is to flood the entire reactor with inert argon gas to exclude air and prevent spontaneous ignition of uranium hydride that may be disturbed in the operations. Because the area is still highly radioactive, remotely operated robots will be used to dismantle the core.
Mr Hickey said: "We no longer think as we arrogantly did in the 1960s that no one knew better than us. If we had a problem we would develop our own research and development to solve it at God knows what cost. Now our culture has changed, now we realise we have a lot in common with other hi-tech industries."
The fire-damaged No 1 pile and its undamaged twin, No 2, are at the base of the two tall concrete towers in the middle of the Sellafield site in Cumbria. They are on an island still controlled by the United Kingdom Atomic Energy Authority (UKAEA) in the middle of the British Nuclear Fuels (BNFL) site.
The costs of dismantling the site are all borne by the taxpayer but mostly come from the budget of the ministry of defence which was seen to "benefit" most from production of plutonium. One of the anti-nuclear lobby's enduring beliefs is that Windscale changed its name to Sellafield in the hope of changing its image. Those on site claim it was merely to distinguish the BNFL site from the UKAEA site. Sellafield continues to recycle spent nuclear fuel.
The chimneys of No 1 and No2 tower above a third UKAEA relic, a giant metal football, prototype of the current generation of advanced gas cooled reactors (AGRs) built for the peaceful purpose of generating electricity. This too is to be taken to specially developed robot machines.
The chimneys are a monument to the late 1940s when Britain was desperate to retain its status as a world power. They were to remove the heat and gases discharged from the uranium in the graphic piles, the whole operation designed to make plutonium - an essential ingredient for hydrogen bombs.
The proof that public safety took second place to the arms race is in the tell-tale square platforms near the top of the chimneys. These contained filters to prevent the people of Cumbria being sprayed with radioactive dust when the piles were operated. Common sense would have dictated that the filters were built at the base of the chimneys but they were almost complete by this time - and so the filters were built at the top and a lift constructed .
"After the war, there was a great public drive for a deterrent so it could not happen again - that is what all this was about," said Rob Dodgson, manager for dismantling the mess that pile No 1 became.
The fire began on October 8 1957 and burned until October 11, when 200 gallons of water a minute were poured into the pile. It was not known that such drastic action would not cause an explosion and meltdown.
As it was, the whole truth was not disclosed. Millions of gallons of milk laced with radioactive iodine were poured down the drain for months as a precaution, but many of the locals out potato picking were not warned of the fall-out. In a calculation 10 years ago the National Radiological Protection Board estimated that around 100 people "probably" died from cancers as a result of the releases over 40 to 50 years.
The cover-up that followed, in which an official inquiry failed to reveal the true extent of contamination, is now part of history. It will have cost £50m by 2008 to remove all the spent fuel and the damaged interior of the pile. The idea is to leave the concrete shell for BNFL to dispose of in the future. This will have to remain until the government has made a decision on the final destination for Britain's nuclear waste.
The metal golf ball is to be left intact until a disposal decision is made.
The giant heat exchangers from the prototype AGR have already been lifted through holes in the roof and taken to the Drigg low-level nuclear dump nearby for encasement in concrete and eventual burial.
It has cost £25m to develop the method for demolishing the reactor and it will cost the same again to take it to bits.
Mr Hickey said: "What we are trying to do is work ourselves out of a job in 10 years - not many people can say they have a job for another 10 years so that is no hardship.
"We have also tried to get rid of the culture of secrecy. People have been fed some duff gen in the past. Now we are all for freedom of information."
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Windscale fire, 1957, and release of polonium
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IOP PUBLISHING JOURNAL OF RADIOLOGICAL PROTECTION
J. Radiol. Prot. 27 (2007) 211–215 doi:10.1088/0952-4746/27/3/E02
EDITORIAL
http://iopscience.iop.org/0952-4746/27/3/E02/pdf/0952-4746_27_3_E02.pdf?origin=publication_detail
The Windscale reactor accident—50 years on
The policy of the government of the United Kingdom to independently manufacture nuclear
weapons in Great Britain was formulated in the mid-1940s and implemented in the late-1940s
and early-1950s; full details are to be found in the monumental treatise on the subject by
Margaret Gowing and Lorna Arnold [1]. A significant component of this implementation was
the construction of a plutonium production factory on the remote coast of the then county of
Cumberland (now part of Cumbria) in north-west England. The site chosen was that of the
former ordnance factory at Sellafield, which, with its sister factory just down the road at Drigg,
had produced TNT during the Second World War. Construction began in September 1947,
and the site was renamedWindscale to avoid confusion with SpringfieldsWorks, the uranium
processing and fuel manufacturing establishment near Preston. Plutoniumwas initially created
in the uranium fuel of two nuclear reactors (the Windscale Piles), chemically separated from
untransmuted uranium and the waste by-products of nuclear reactions in a reprocessing plant,
and then converted to metallic form before being sent to the Atomic Weapons Research
Establishment at Aldermaston, near Reading, for machining and assembly as a weapon. The
speed with which the policy was put into practice is truly remarkable: Windscale Pile No. 1
was operational in October 1950 followed by Pile No. 2 in June 1951, the first reprocessing run
took place in 1952 and the extracted plutonium provided the explosive material in the UK’s
first nuclear weapons test (in Australia) on 3 October 1952, just five years after building work
commenced at Windscale. This speed, however, was achieved at a premium, as we shall see.
TheWindscale Piles were each fuelled by 180 t of uranium metal fabricated (at Springfields
Works) into >70 000 aluminium-clad elements positioned in 3440 horizontal channels within
nearly 2000 t of graphite moderator. The reactor core was cooled by blowing a large volume of
environmental air through the channels and out of a 120mhigh chimney—in contrast to power
reactors, in the Piles the heat generated by nuclear fission was purely incidental to the creation
of plutonium for military use. Although the primary purpose of the Piles was the production of
weapons-grade plutonium, the reactors were also used to generate other nuclides through the
neutron irradiation of appropriate materials fabricated as ‘isotope cartridges’ that were suitably
placed in channels within the core. Thus, the α-particle emitter 210Po, used in combination with
9Be as a neutron source to trigger nuclear fission chain reactions, was produced in bismuth oxide
cartridges (codenamed ‘LM cartridges’) and tritium was manufactured using magnesium–
lithium alloy cartridges (codenamed ‘AM cartridges’). (Other nuclides, such as 232Th, 237Np
and 59Co, were also irradiated in the Piles at various times during their operational lives.)
These isotope cartridges depressed the neutron flux in the core, and, when uranium enriched in
235U became available from Capenhurst Works (near Chester) in 1953, low enriched uranium
fuel was used in the Piles to counter the adverse effects of the isotope cartridges on the neutron
economy of the reactors.
The Windscale Piles posed problems to their operators throughout their service. Indeed,
even before construction was completed Sir John Cockcroft, on the basis of information
received from the USA, insisted that filters be installed to remove radioactive material
potentially present in the exhaust cooling air, which, since construction of the stacks had
already commenced, necessitated the building of filter galleries (‘Cockcroft’s follies’) towards
211
212 Editorial
the top of the chimneys. It was predicted at the design stage that occasional failures in the
aluminium cladding of fuel elements could lead to releases of fission products into the cooling
air, and radiation detectors were installed to locate channels where a ‘burst’ had occurred so
that the affected channel could be cleared of fuel before the core was contaminated. Such
bursts did occur throughout the period that the Piles operated, and kept the workforce busy. It
was also anticipated that the flow of cooling air would be sufficiently great that fuel elements
would be buffeted and might move along the channels, and steps were taken to attempt to
prevent this; but it was found that, in practice, elements were being blown out of the core,
leading to a re-design of the arrangement of elements in a channel.
The fuel element ‘blow outs’ were accompanied by other, unforeseen, events: some
elements were found to have become stranded, on discharge, in locations where the irradiated
metallic uranium fuel became oxidised in the cooling air and radioactive particles were being
released from the chimneys into the environment. The magnitude of these particulate releases
varied over the lifetime of the Piles, but they were a constant problem for the operators; these
fuel particle releases have been described in detail by Andrew Smith and his colleagues in the
June issue of this Journal [2]. Another unexpected operational challenge was Wigner energy
stored within the graphite moderator. When graphite is bombarded by neutrons, carbon nuclei
are displaced in the lattice, which, at the relatively low operating temperature of the Piles,
increased the potential energy of the graphite. This stored Wigner energy could, if released
in an uncontrolled manner, lead to localised high temperatures and the possibility of a fire.
The firstWigner energy release in theWindscale Piles took the operators by surprise, but once
the process was understood, controlled releases of Wigner energy were conducted in regular
annealing procedures. It was the ninth anneal in Pile No. 1 that led to a fire in the core during
10–11 October 1957 and the consequent release of radioactive material from the Pile chimney
that is the worst accidental discharge of radionuclides that has been experienced in the UK; a
comprehensive description of the accident has been provided by Lorna Arnold in her highly
impressive book on the subject [3].
The Windscale fire had profound political effects and the UK Atomic Energy Authority
(UKAEA) that ran the British nuclear facilities was never to be the same again. The
two Windscale Piles were permanently closed, although this did not greatly influence the
weapons production programme as eight UKAEA-owned Magnox reactors—of a much more
sophisticated design than the Piles, and which were also used to generate electricity—were
coming on-line at Calder Hall, adjacent to Windscale Works, and at Chapelcross, in southern
Scotland. Aninquiry into theWindscale accident, chaired by SirWilliam Penney,was instituted
by the UK Government within days of the accident, and the Penney Committee submitted its
report to Government on 26 October, a remarkably short time after the accident. The Prime
Minister, Harold Macmillan, whose government was involved in delicate negotiations to reestablish
nuclear weapons cooperation with the USA, decided that just a summary of the
Penney Report should be published [4], and the full report was only made public 30 years
later (and is included as an appendix in Lorna Arnold’s book [3]). A committee chaired by
Sir Alexander Fleck then investigated the wider implications of the accident, which led to,
among other things, the establishment of the National Radiological Protection Board (NRPB)
in 1971 (since 2004, subsumed within the Health Protection Agency as the Radiation Protection
Division).
The Penney Committee guardedly concluded that an uncontrolled localised release of
Wigner energy during the ninth anneal had led to a fire in a fuel element that had then spread
to involve about 10 t of uranium. At the time, some senior and experienced people in the
UKAEA expressed their doubts over this explanation, and pointed to evidence that an AM
cartridge (made of magnesium–lithium alloy) was likely to have been the initiator of the fire
Editorial 213
[3]. Evidence that accumulated after the Penney Inquiry and which was presented to the Fleck
Committee, such as the seriously damaged AM cartridges that were removed from Pile No. 2
in 1958, tended to support this alternative view; but one gains the impression that the somewhat
battered UKAEA wanted to ‘move on’ after the accident, and that the cause of the accident
as identified by the Penney Inquiry should be regarded, if at all possible, as ‘the final word’.
Whatever the actual cause of the fire, it is difficult to disagree with Lorna Arnold’s view that
the operation of the Windscale Piles was ‘an accident waiting to happen’ [3].
The first reports of the activities of radionuclides released during the accident, and of
their travels, were published during 1958–59. It was clear from these reports that the primary
radiological hazard arose from 131I, although the major emissions of other fission products were
also quantified. Three reports [5–7] made mention of the release of 210Po (from the affectedLM
cartridges), although no quantification of the activity discharged was offered, and no reference
was made to tritium having been released (from the affected AM cartridges) although this
was likely to have been of relatively minor radiological significance. Given the sensitivity
surrounding the fire and, in particular, the involvement of the LM and AM cartridges, it may
be that the 210Po discharge was only acknowledged because it was known that the radionuclide
had been detected in the Netherlands [8]. The release of 210Po was not even mentioned in the
next official report, published in 1960, of the environmental aspects of the accident [9]—an
omission that Lorna Arnold describes as ‘incomprehensible’ [3]—encouraging the inference
that the authorities did not want to unnecessarily shine a spotlight on difficult issues that
might conveniently be considered ‘closed’. Without doubt, the high security classification
assigned to the production of weapons materials at that time, together with the ‘need-to-know’
principle, would have offered little assistance to any comprehensive ‘external’ investigation of
the radioactive materials discharged during the fire. Against this conspiratorial interpretation
is the unclassified UKAEA report published in 1959 [10] which examined the α-activity found
on air filters atWindscale, at the Harwell nuclear research establishment (south of Oxford) and
in Belgium and concluded that this was principally due to 210Po, and a further Harwell report
written in 1961 and declassified in 1962 [11] which makes extensive reference to 210Po activity
in air concentrations measured in the UK and the rest of Europe using data gathered under the
auspices of the Advisory Committee on Nuclear Radiation of the International Geophysical
Year (IGY; July 1957 to December 1958). These two UKAEA documents make the failure to
estimate the magnitude of the 210Po activity discharged during the accident in reports published
during the years immediately following the fire even more perplexing.
J R Beattie [12] and Roger Clarke [13] later re-evaluated the activities of the fission
products released from the uranium fuel during the accident, but the next thorough examination
of the quantities of all the radionuclides emitted during the Windscale fire was conducted
almost a quarter of a century after the accident by Arthur Chamberlain of Harwell [14], who
was heavily involved in the original assessment of the environmental impact of the accident.
In addition to fission product activities, Chamberlain quantified the releases of 210Po and 3H.
Unfortunately, Chamberlain’s report relied on some material which was still classified at that
time, so that his report was also classified (it was declassified in 1983) and not known to
Malcolm Crick and Gordon Linsley, two scientists from the NRPB who were investigating the
risks to public health posed by theWindscale accident. As a consequence, their first assessment
[15] did not consider 210Po, a fact that was pointed out by John Urquhart [16]. In an extension
of their original study, Crick and Linsley [17, 18] examined the risks resulting from the release
of both 210Po and 3H, as well as a number of minor radionuclides. Interestingly, Crick and
Linsley [18] concluded that although the risk of thyroid cancer from exposure to 131I remained
the greatest radiological impact of the fire, the predicted health effects of exposure to 210Po
came in a close second. Roger Clarke [19], using updated cancer risk coefficients, estimated
214 Editorial
that the accident had caused, or would cause, ∼100 fatal cancers (of which <10 are thyroid
cancers due to exposure to 131I and ∼70, mainly lung cancers, are due to exposure to 210Po)
and ∼90 non-fatal cancers (of which ∼55 are thyroid cancers due to exposure to 131I and ∼10
are due to exposure to 210Po)—the release of the now notorious polonium-210, which was
largely ignored in early environmental assessments, was considered by Clarke to have had the
greatest radiological impact of the radionuclides discharged during the Windscale accident.
Recently, John Garland, the late Arthur Chamberlain’s long-time colleague at Harwell, has
refined the estimates of the quantities of radionuclides released during the fire [20], using
original documents and information on the travel of radioactive material provided by the Met
Office using the NAME atmospheric dispersion model and detailed meteorological data for
October 1957 [21].
The half-century that has elapsed since the Windscale fire has provided some perspective
on the accident—the quantity of 131I released was 1000 times less than that released from the
Chernobyl accident almost 30 years later. Nonetheless, the Windscale accident can hardly be
considered as trivial—it is rated as a Level 5 accident on the International Nuclear Event Scale
(INES) [22]—and it could have been a lot worse. The extensive environmental monitoring that
took place during and after theWindscale fire provided the evidence upon which the authorities
decided that a milk distribution ban should be enforced in the west Cumbrian coastal strip
running from 10 km north of Windscale Works to some 20 km to the south. Iodine-131 had
been quickly identified as the major radiological hazard arising from the accident, although
the health physicists had little guidance available as to what constituted an acceptable limit
for the level of 131I activity in milk, and they derived, essentially from first principles, such a
limit (0.1 μCi/L) to constrain thyroid doses, particularly to infants and young children. A milk
ban based on these ad hoc calculations was a courageous but wise decision, which prevented
a significant enhancement of the local collective thyroid dose and limited individual thyroid
doses. The environmental monitoring programme was described in detail by John Dunster
and his UKAEA colleagues from Windscale, Huw Howells and Bill Templeton, at a large
international conference organised by the United Nations and held in Geneva in 1958 [7]; but
this conference paper is not now readily accessible. Hence, it has been decided to reproduce
the paper in this issue of Journal of Radiological Protection as a tribute to the substantial
efforts of John Dunster, Huw Howells, Bill Templeton and their many co-workers to swiftly
understand the potential radiological consequences of the fire and, where possible, limit its
impact. This reproduction has been made possible by the goodwill of the United Nations (and
the good offices of Malcolm Crick) and Rose Dunster, John Dunster’s widow, to whom thanks
are due.
References
[1] Gowing M and Arnold L 1974 Independence and Deterrence: Britain and Atomic Energy 1945–1952 2 vols
(Basingstoke: Macmillan)
[2] Smith A D, Jones S R, Gray J and Mitchell K A 2007 A review of fuel particle releases from theWindscale Piles,
1950–1957 J. Radiol. Prot. 27 115–45
[3] Arnold L 1995 Windscale 1957. Anatomy of a Nuclear Accident 2nd edn (Basingstoke: Macmillan)
[4] Atomic Energy Office 1957 Accident at Windscale No. 1 Pile on 10th October, 1957. Cmnd. 302 (London: Her
Majesty’s Stationery Office)
[5] Stewart N G and Crooks R N 1958 Long-range travel of the radioactive cloud from the accident at Windscale
Nature 182 627–8
[6] Crabtree J 1959 The travel and diffusion of the radioactive material emitted during the Windscale accident Q. J.
R. Meteorol. Soc. 85 362–70
[7] Dunster H J, Howells H and Templeton W L 1958 District surveys following the Windscale incident, October
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