An acetylene cylinder can become unstable and potentially explode if a flashback occurs, triggering decomposition of the gas inside. While an explosion may be rare immediately after a flashback, decomposition can continue for hours, requiring emergency services to cool the cylinder with water for many hours or days before it can be safely moved. These incidents endanger anyone near the cylinder and emergency responders. To prevent flashbacks, proper training, equipment maintenance, procedures, and safety precautions should always be followed when using oxy-acetylene equipment. If a flashback does occur, closing the gas cylinders and evacuating the area if decomposition appears to be progressing is important.