HC Deb 25 April 1961 vol 639 cc32-3W
Mr. Pavitt

asked the Secretary of State for the Home Department, in view of his responsibility with regard to civil defence, how many square miles he estimates would be subject to the local fallout of radioactive particles giving a dose of at least 800 roentgens in the open in the first 48 hours, after the detonation of a 10-megaton bomb.

Mr. R. A. Butler

This would depend on a number of factors such as weapon design and meteorological conditions, but assuming a ground burst weapon and a 50 per cent. fission yield, the area so contaminated might be about 2,000 square miles.

Mr. Pavitt

asked the Secretary of State for the Home Department, in view of his responsibility with regard to civil defence, how many million curies of strontium 90 he estimates would be created in the event of an explosion involving 3,950 megatons of nuclear bombs; and what would be the percentages of local fall-out and world-wide fall-out.

Mr. R. A. Butler

The amount of strontium 90 which would be produced would vary greatly with the types of bomb which were used. The percentage of local and world-wide fall-out would vary with the circumstances. This variation would extend from almost nothing up to about two-thirds for local fall-out with world-wide fall-out constituting the remainder.

Mr. Pavitt

asked the Secretary of State for the Home Department, in view of his responsibility for civil defence, what estimate he has made of the number of people who would suffer sever, but not fatal, thermal injury if a 10-megaton bomb fell on the following cities, London, Glasgow, Manchester, Birmingham, Cardiff, and Bristol; and what civil defence arrangements have been made to deal with possible mass-burn casualties.

Mr. R. A. Butler

The number of people receiving injuries of this nature would depend on a number of variable factors and no reliable estimate can be given. For example, the simple act of taking cover would greatly reduce the potential casualties from this hazard. The planned medical arrangements take account of the need to deal with casualties from this as well as from the other effects of nuclear weapons.