Objective: To create an instrument to assess the professional competence of nurses in emergencies. Method: Methodological study carried out between 2013 and 2016 in a Brazilian university. We used the Pasquali's model and Psychometrics as references because they allow subjective phenomena to be measured. The survey covered defining steps of the behavior to be measured, the formulation of the items in the instrument, development of instructions for using the instrument and elements necessary to demonstrate validity evidence. Although we have previously performed, in a distinct and consecutive way, the literature review, definition of the Core (or Matrix) Competence and the Competence Profile, and identification of validity with Delphi, essential components to structure a technology, in this step we continued the conclusion of these Theoretical Procedures. Result: We created an instrument for self- and/or hetero-evaluation containing: personal/professional/academic characterization, Competency Scale, fictitious cases and actions representing the practice. Conclusion: We created a new soft-hard technology based on the validity evidence of contents according to experts of the five regions of Brazil.