Despite the profusion of literature associated with analytical atomic spectrometric techniques, very little has been reported concerning the development of detector systems. This is particularly surprising in view of the current trend in atomic spectrometry towards the use of non-flame atom reservoirs. These devices frequently produce weak transient signals and dc level detector systems designed for steady state measurements are in consequence often unsatisfactory. High speed recorders may be used with success providing the total response time of the various electronic components is comparable with or preferably less than that of the signal duration and only in such instances will precise measurement of the signal be achieved (1,2). The use of absolute integration techniques are obvious for this type of measurement, although their application has not been particularly forthcoming to date. Photon counting would seem to have many advantages for such purposes, although with the exception of the more general studies of Morton (3) and Malmstadt and co-workers (4) it has received so far little consideration. Indeed its use as a detection system in analytical atomic fluorescence and emission spectrometry has yet to be reported.