"Faults Of Judgment" In Nuclear Mishap From Our Science Correspondent The Prime Minister yesterday announced in the House of Commons the setting up of three committees under the chairmanship of Sir Alexander Fleck, F.R.S., chairman of Imperial Chemical Industries, Ltd., with the object of ensuring that lessons learned from the accident at the Windscale plutonium pile on October 10 should be fully digested and applied. The three committees will be responsible respectively for the evalu- ation of technical data, a review of the organization and staffing of the authority's production plants and research reactors, and for a review of health and safety organization. The appointment of an " independent person of standing, who has experience of large-scale organizations operating processes involving hazardous mate- rials," had been suggested by Sir Edwin Plowden, chairman of the authority, to the Prime Minister. PREVENTING RECURRENCE The Prime Minister gave an assurance that the accident had no bearing on the safety of the nuclear power stations being built for the electricity authorities. He recalled that during the past 12 years Britain had built up this new industry without a single serious injury caused by radiation, and said that there was no evidence that the Windscale accident had done any significant harm to any person, animal, or property. He paid tribute to the quiet confi- dence and absence of alarm of the general public in the area. The Prime Minister said that it was important now " on the one hand to do all that is possible to ensure that there will never again be a similar occurrence, and on the other to see how the organi- zation of the authority can be improved in the light of the Windscale experience." In reply to a question, Mr. Macmillan said that " no particular or special experiment either for civil or military purposes was being done at the time." NO ACTION The cause of the accident was summarized by the Prime Minister and further details were given by the com- mittee of inquiry in a White Paper issued soon after Mr. Macmillan's statement. The Atomic Energy Authority, through its chairman, Sir Edwin Plowden, in the White Paper stated that they accepted collective responsi- bility for weaknesses in organization, to which faults in operating judgment were attributable. No disciplinary action was being taken. They were taking immediate steps to deal with these weaknesses, and suggested the indepen- dent review for which Mr. Macmillan has arranged. To ensure closer liaison between the management and local interests, a stand- ing liaison committee had been set up at Windscale, and similar committees were being set up at all other operating factories of the industrial group. They were also reviewing liaison with local interests in their other groups. The primary cause of the accident, stated the committee of inquiry in the White Paper, was the way in which a routine operation was carried out, the purpose of which is to release, in the form of heat, internal strains in the graphite of these reactors caused by some of the atoms of the graphite having been knocked from their normal posi- tions by neutrons during the previous operation. This is done by arranging for the nuclear heating of the reactor. Thinking that the temperature, after a first heating, was falling sooner than it should have-a conclusion with which the committee disagreed-the physicist in charge decided on a second heating. This was done " too soon and too quickly." HIe was provided with no manual giving detailed instructions for this operation, known as a Wigner energy release. There were also two separate deficiencies in the instrumentation of the pile, the effect of which was to cause the temperatures reached in the fuel elements to be underestimated. And a "1 scanning " equipment-used in looking for burst fuel cartridges-was found to have jammed. This had happened during a previous Wigner release, probably because of heat. EXPOSURE TO AIR The committee thought that the most likely next development was the slow combustion of uranium fuel elements, which had become exposed to the air in consequence of the heating. Other cartridges were in the reactor which con- tained lithium-magnesium alloy. Although the use of these is not men- tioned in the report, it is known that interaction between lithium and neutrons during the normal working of a reactor leads to the formation of tritium, under- stood to be one of the materials used in thermonuclear weapons. It was thought possible, but unlikely, that a failure in these cartridges could have contributed to the accident. At a Press conference yesterday Sir William Penney, who was chairman of the committee of inquiry, agreed that magnesium burnt readily in air when started, but thought this no more likely than combustion in damaged, ordinary fuel cartridges. DELAY OVER MILK A report by a committee set up by the Medical Research Council, which is included in the White Paper, supported the general measures taken for the pro- tection of workers and public. They were satisfied that it was most unlikely that any harm had been done to the health of anybody. But certain weaknesses in organization were apparent-notably the delay between recognition of an accident and the institution of extensive and rapid milk sampling throughout the area of possible risk. Further, certain gaps in scientific knowledge were revealed. For their part, the Atomic Energy Authority have asked for the laying down of maximum permissible levels of exposure to radioactive substances when exposure is for a limited period rather than as a continuous lifetime dose. Summary of the White Paper, page 4. Pictures, page 14. "FAULTS OF JUDGMENT " IN NUCLEAR MISHAP STEPS TO REMEDY WEAKNESS IN ORGANIZATION SIR A. FLECK TO HEAD THREE COMMITTEES