A study to evaluate the exhaust noise environment of a proposed high Reynolds number tunnel (HIRT) has been conducted. During an earlier phase of this study, prediction of the noise environment resulting from both the starting transient and steady-stage operation of the facility was performed. Also, a model test program was specified to experimentally evaluate the exhaust flow noise. The results of the model test program and new predictions of the full-scale HIRT exhaust noise, based on the model data, are the subjects of the report. (Author).