The problem of identifying reproducible frequency bands useful for the nondestructive evaluation of steel plates using the dynamic acoustical intensity scanning concept (DAIS) is addressed. Reproducible frequency bands are essential so that subsequent changes in sound intensity patterns can confidently be attributed to structural changes rather than to random fluctuations. A number of evaluation methods are tried. Stationary frequency bands are identified by all methods in the range of 100–4000 Hz. The most sensitive and practical evaluation method is deemed to be the comparison of intensity versus time data collected separate from the plate scans. This method is accurate, convenient, and can be automated to exclude all unwanted frequency bands during testing. The remanent intensity factor technique, while useful in identifying stationarity, is less sensitive and more difficult to implement.