Summary: The Regnault Method as applied to tritium purity determinations is described. The operating difficulties, such as temperature and humidity changes, static charges, excessive vibrations, contamination with air and helium, etc., and the methods currently in use for minimizing such difficulties, are discussed. A discussion of ion-chamber calibrations, and the correlation of ion-chamber results with Regnault Method results, are included. A precision of ±1% has been obtained, but the accuracy is not yet known.

The purpose of this note is to recalculate the semi-empirical curve of neutron yield vs. deuteron energy originally obtained by H. York in order to predict, using it and the best available data, what yields may be expected for deuterons on uranium in the extrapolated energy region.