None

A nontechnical description of the mechanisms of local and world-wide fall-out from nuclear explosions is given. The relative importance of local fall-out in a nuclear war is discussed. The effects upon man of world-wide fall-out from past nuclear testing is discussed. It is pointed out that doses to man frcm testing are quite small when compared to the natural radiation background. (auth)

Experiments were carried out on a Cs/sup 137/ plaque source of 40 x 40 x 1/2 inches. Measurements were made of dose distributions in water and of photon spectral distributions in paraffin. For 9-inch-thick water siab absorbers without air gaps, it was found from the preliminary experiments that the depth dose uniformity can be varied over the range 1.10 to 1.40. The absolute dose rates found were in general agreement with design predictions which indicate irradiator efficiencies in the region of 50% and dose rates in the region of 1 Megarad/hour for high-level indicators. (W.D.M.)

An instrument has been developed for the detection of uranium dust in the atmosphere. The principle feature of this device is its ability to indicate a gross release of alpha radiation within a few minutes of its occurrence. The unit will sound an alarm when either the indicated level or the rate of increase exceeds preset values above normal background variations. (auth)

The criteria and methods for test evaluation of electromagnetic clutch characteristics are discussed. An evaluation of the relative merits of two commercial clutches, both of the multiple disk friction type, is presented with test results. One of these clutches was incorporated in the clutch assembly design for the Array Reactor (SM-2). (auth)

None

None

None

None

None

Several safety parameters are calculated for a large, fast, Na-cooled, oxide-fueled reactor. The Doppler coefficient is studied as regards its effect on the reactivity during a power excursion, and its dependence on the neutron spectrum, on the concentrations of U/sup 238/, Pu /sup 239/ , a nd Pu/sup 240/, on spatial temperature and power distributions, and on temperature. Other parameters studied include the Na temperature coefficient of reactivity, and the reactivity insertion caused by total Na loss; reactivity coefficients caused by thermal expansion of fuel and steel cladding; the excess operating reactivity; and the reactivity caused by a fuel slump. The effects of a Be reflector on neutron lifetimes are determined. The safety aspects are balanced against economic considerations. (T.F.H.)

This document discusses a proposal that certain presently installed reactor process water outlet temperature data logging equipment in subject reactors to be replaced with new functionally simplified equipment of a more adequate design. The primary purpose of the proposed installation is to replace existing equipment which is obsolete and in three reactors is worn out to the point where the equipment is out of service frequently for periods of time up to 8 hours or more. The new equipment will provide reliable process tube temperature information for use in the functions of reactor control and product accountability. Based upon anticipated incremental production gains resulting from use of the new equipment, the amortization period for the project is calculated at 2.7 years.

The purpose of this report is to establish the scope of a project to provide a system which will quickly and accurately identify the sources of all reactor scrams.

None

Overbore fuel for charging under the proposed Plant Improvement Program is fabricated according to the standard ``F`` process with a few exceptions. Due to the size and weight of individual components and cores, it was necessary to modify the process and change several of the process times to produce a fuel of equal or better quality than standard production. The additions and modifications to the standard lead-dip fuel element manufacturing process are required for production of Model CVIN fuel elements and are discussed in this report.