The main object of this NORDTEST project has been to cover the requirements for standardization of the rules of computer-controlled reverberation time measurements with real-time frequency analyzers. The dependence on different test variables have been studied with extensive laboratory experiments. The most important experience is that the test signal shall be 1/3-octave filtered noise to avoid errors caused by leakage from adjacent frequency bands. The implications of the test rules were further studied through comparison experiments with self-contained instruments and Scandinavian laboratories. As a result of all these experiments a proposal for a new Nordtest method was compiled.