Reverberation chambers (RCs) are cheaper alternatives to anechoic chambers (ACs), and they are mainly made up of metal (ideally perfect and smooth) covered rooms. Their designs are not sophisticated as in AC, and EMC tests at precompliance level can be applied within a certain interval of error. For applying EMC tests to any equipment under test (EUT), the electric field uniformity in the room must be satisfied within a certain error. The volume having a uniform electric field is called as working volume (WV) where EUT for being subjected to EMC tests will be placed in. Positions and dimensions of scatterer such as Tx antenna that must be in the room determine the dimension of WV. Classically, position of transmitting antenna is changed continuously and randomly till obtaining WV and this process ends at any time within 3 days. Industry is always hurried and wants to know when to start testing. In this study, a fast and novel method with data mining has been proposed for overcoming this problem, and it achieves a success rate of 96% in 4-5 hours. The model was tested for 10 different angles of rotation of the stirrer and 97% accuracy was achieved.