download: 887-6167-4-PB.pdf .The Brazilian standard ABNT NBR 15200: 2012 details a procedure for decreasing the required time of fire resistance in buildings with good fire safety characteristics. It called equivalent time method. This name can confuse the less habituated to the fire safety area, because the Brazilian procedure is not equal to the original equivalent time method, European. The purpose of this paper is to discuss the equivalent time method, to detail the origins of the Brazilian method and present their limitations no explicit in the Brazilian standard. Some unknown aspects of most researchers or technical means are presented. It should be highlighted the abundant bibliography presented to aid the understanding of a seemingly simple issue, but it incorporates many concepts of fire safety, not always understood by the users.