ICRP Main Commission Meeting

1956 October 31 – November 6, New York, USA

A discussion was held regarding matters related to the preparation of the new ICRP report. Topics for discussion were related to uncertainty regarding data, lifespan reduction, and clarification of other items. It was agreed that the statement in ICRP/56/17 covered the situation until the age of 30 well. No conclusions were reached regarding increasing the rate after a certain age, or what the dose limit per year should be.

This topic was revisited the day after and following further discussion, the Chairmen presented the following limits which were approved: 50 rem until 30th birthday with 50 rem/decade afterwards, 5 rem/year average with not more than 10 rem/year, and not more than 3 rem/quarter year. The basic permissible dose was established as 0.3 rem/week. No decision was reached regarding limit on emergency dose or occupational dose due to limited numbers of ICRP members present. Further dose limits were discussed regarding the eye and skin but no decision was reached. The Commission decided to include a recommended figure for average population total dose up to age 30 which would include age 30. The final wording was decided upon the following day.

Report of Committee 2 – Dr. Morgan presented work on the report and discussed with the Commission issues related to weighted effective energy, weighted coefficients for organs, limits for different organs and tissues, and studies based off of different radionuclides. No decision was made by the Commission.

The Commission discussed organisational matters relevant to ICRP such as the structure of the organisation which included matters concerned with lack of paid secretariat to aid in publishing of reports, and selecting members purely on a technical, instead of national basis. No concrete decision was reached.

Regarding the topic of average population dose, it was decided to draw attention in the report to the fact that countries will have to allocate the available dose. The decision that for the whole population the critical organ to age 30 was the gonads, and that the occupational doses referred to all the critical organs (with that to the skin doubled) was agreed.

It was agreed that the average rate should be equivalent to 5 rem/decade (10 mrem/week).