Abbreviations for "decay per minute" and "decay per second," respectively, units used in the measurement of rates of radioactivity. 1 dps is properly called 1 becquerel (Bq). 1 dpm is equal to 1/60 becquerel or 0.45045 picocuries
Russ Rowlett (Director), How Many? A Dictionary of Units of Measurement, Center for Mathematics and Science Education University of North Carolina, USA 2005. http://www.unc.edu/~rowlett/units/dictA.html, (Unit of Meas and Covr Factors - Amer) {608}