In what order should you turn on the gases when igniting the torch?

When igniting the oxyfuel torch, it's essential to turn on the acetylene first, followed by the oxygen. This sequence is crucial for safety and proper operation. When acetylene is first introduced, it creates a fuel-rich mixture suitable for ignition. Turning on the oxygen afterward allows for a controlled increase in the oxygen concentration, which helps create the desired flame characteristics without risking backfire or flashback—a dangerous situation where the flame travels back into the hoses.

Furthermore, if oxygen were to be turned on first, it could create a high-pressure situation that might lead to the acetylene igniting too rapidly or unpredictably, increasing the risk of an accident. Thus, following the correct procedure of turning on the acetylene first ensures both safety and effective use of the torch. This order is standard practice in oxyfuel cutting and welding tasks.