Health, comfort and the job efficiency of the crew of offshore platforms are factors deeply related to the acoustic quality of the places. The acoustic project of platforms include the noise prediction. It is a complex problem, because it involves several noise sources and receptors. Numeric methods such as Boundary Element Method and Finite Element Method are not still fully satisfactory for use in complex acoustic problems. This way, semi-empiric formulas and statistics methods are used in the prediction calculations. This paper describes some aspects of the Petrobras experience, along the years, in the performance of acoustic projects in offshore platforms. Finally, in this work, some important decisions are discussed for improvement of the acoustic quality of those operational units.