periodically the Industrial Hygiene Unit has the occasion to perform efficiency tests on respiratory protective devices and on filter cartridges used with these units. A study of the relative merits of the flame photometer and conductivity meter was made to determine which is more applicable for the determination of NaCl in filter samples.

Recent developments in the field of photoconductive devices made possible the simplification and attendant improvement of the recording anemometer system used with the portable meteorological mast. The purpose of the work was to produce a simple, reliable recording anemometer system compatible with the project's existing instrumentation. Of primary importance was reduction of maintenance without loss of accuracy. This report discusses some of the factors considered in the design of the system, describes in detail the electronic circuitry and mechanical components, and presents some performance data. The data obtained from a twenty-four hour trial run indicates that the system has fulfilled the requirements.

Transfer operations of highly radioactive solutions by the normal transfer pipette leads in most instances to a spread of contamination in the shielded facility. In the dripless pipette, the solution is held in the reservoir by the use of the siphon principle.

The monocarbide and the mononitride of uranium are potentially useful ceramic nuclear fuel materials. This paper reports the results of exploratory investigations of the reactions of uranium monocarbide and uranium mononitride with boiling water. Uranium dioxide, chemically stable in deoxygenated boiling water, was used as a control.

Judging scratch depth or surface roughness by unaided visual inspection under controlled conditions, while rapid and popular, is not quantitative. Comparison methods improve reproducibility but are generally not applicable to evaluation of depths of single widely spaced scratches. Stylus-type contour recorders yield valuable scratch contour data but may themselves plow through soft materials and fine details. Depth measuring microscopes are particularly applicable to measurement of pinhole depth but do not graphically reveal profiles and provide only a small field of view. The comparatively large field of view and graphic display of contour provided by profile microscopes make them particularly suitable for evaluation scratch depth as well as surface roughness. A HAPO-constructed instrument has demonstrated an accuracy of +/- 50 micro inches in the range of 50 to 15,000 micro-inches scratch depth. It is a pocket-sized, portable, and can be used on horizontal and vertical surfaces by untrained persons with only brief instruction.

A test program conducted to develop high integrity piping and seal components for Plutonium Recycle Test Reactor installation. Methods of preventing leakage of costly D2O coolant and maintaining operational safety were investigated.

Designing a dissolver safe for up to 5 per cent U.235 enriched NPF's and having a one a ton per day capacity is a fundamental problem of Hanford NPF Program. Two basic design concepts have so far evolved, both of which employ a recirculating system in which the fuel elements are placed in the critically safe geometry separated from the bulk of the solution in another vessel. In one concept the fuel elements are charged to a set of geometrically safe cylinders or tubes and solution is circulated through them/ In the other concept the fuel elements are placed on a flat tray while solution is sprayed over them. In the latter system, nuclear safety is obtained by avoiding submerged dissolution and the resulting neutron moderation by the solution.

Facilities shall be provided in the 221-U Building for storing the metal solution product of the dissolution step in existing tankage from U, T, and B Plants until a reprocessing campaign is scheduled through Redox. This section shall provide a sampling tank for fuel accountability sampling and a pump tank from which the solution will be pumped via a cross-country pipeline to Redox for further processing.