Experimental data pertinent to the evaluation of hazards involved in the exposure of personnel to tritium and tritium oxide are reviewed. Conclusions are drawn and recommendations made with regard to the control of these hazards.

The prompt administration of zirconium citrate was at least twice as effective as the prompt administration of calcium disodium salt of ethylenediaminetetraacetic acid (CaEDTA) in preventing deposition of plutonium in the skeleton. On the other hand, CaEDTA was twice as effective as zirconium citrate in preventing the deposition of plutonium in soft tissues. The combined administration of zirconium citrate and CaEDTA was the most effective treatment for preventing the deposition of plutonium in the total rat. Zirconium malate offered no advantage over zirconium citrate, and appeared to be somewhat more toxic. Three doses of the zirconium salts over a four-day period were no more effective than a single dose.

The investigation to be described in this paper was one of several undertaken to resolve a curious discrepancy that had arisen in measurements of the diffusion length of graphite. Those diffusion lengths measured with the graphite layups of 100 Area piles were three to six centimeters higher than the value obtained with the Hanford Standard Pile. The fact that the 100 Area structures of the order of 40 ft. X 40 ft. X 30 ft, not including reflector, approximated an infinite medium, whereas sigma piles are of the order of 8 ft. X 8ft. X 10 ft., suggested the possibility that the diffusion length obtained by mensuration of relative fluxes and application of the conventional equations depended in some way on the size of the medium. Therefore, in order to determine if such a dependency actually exists, it was proposed to erect a series of graphite stacks of different dimensions and to make diffusion length measurements in each.

Temperature calculations have been made to aid in planning a production test for low level irradiation of the thin rectangular uranium wafers. These uranium wafers, under irradiation in the outer fringe sone, are expected to have a maximum temperature which is less than 10 C above the local water temperature.

The purpose of this manual is to present available data which can be used to determine disintegration rates of radioactive samples from counting rates measured under given circumstances with routinely used laboratory instruments. There is also brief discussion on the methods by which the various factors have been determined with reference to the accuracy with which they are known and to what extent the finally quoted disintegration rate is affected by these errors. Emphasis has been placed on those isotopes of particular interest to Radiological Sciences programs and the manual is intended as a standard through the use of which comparable values can be reported from all units in the Department.

The Hanford Remote Pipetter has developed into a very useful tool for routine pipetting by semi-skilled non-technical personnel. Radiation exposure to the operators has decreased to normal background levels as proper shielding exists between the sample and the operator. The results achieved by the pipetter have demonstrated its flexibility and simplicity of operation.

The feasibility of using Teflon bellows as the pulsing device for solvent extraction pulse columns has been previously demonstrated by life test of various sizes of Teflon bellows. This report describes a compact Teflon bellows pulse generator and drive assembly which was designed, built, and tested by the Chemical Development Unit. The pulse generator assembly is suitable for a number of applications where pulse generators are required to pulse solvent extraction columns.