Abstract: The invention relates to a method and apparatus for oxygen cutting pieces of steel, in which a cutter member (5) is positioned above a top face of the piece to be cut, and trimmer and spray members (10, 11) are positioned beneath the piece to be cut, said members being carried by a support blade which passes through the cut slot. According to the invention, at least one pressurized fluid (22) is projected directly into the cut slot (1.3) and into the portion thereof that lies between the cutting front and the blade-shaped support of the cutter and spray members, said jet forming a barrier protecting said blade-shaped support against particle projections during forward advance of the support along the cut slot (1.3). This eliminates the risk of forward advance of the blade-shaped support in the cut slot encountering any obstacles, thereby making it possible to implement cutting speeds that are very high.