Final answer:
The last step in shutting down an oxyfuel gas cutting or welding outfit is to close the oxygen and fuel gas cylinder valves to ensure safety.
Step-by-step explanation:
The last thing done when you shut down an oxyfuel gas cutting or welding outfit is to close the valves on both the oxygen and fuel gas cylinders. This is a critical safety measure to prevent any gas leaks or accidental ignition when the equipment is not in use.
After closing the cylinder valves, the next steps involve bleeding the gas lines to remove any residual gas and then shutting down the torch.