MeTrao is a system used to obtain information about the current sound levels and that records measured sound levels, providing insight into the history of the values measured. The system was developed based on experiences from practice, to meet all requirements the current regulations, the local government and the customer have with regard to sound level registration. It gives the sound technician, operator/organizer and government a tool for the proper management and recording of the sound levels in halls, theaters clubs and events for instance.