A scan data collection operation includes performing a scanning operation using a scan path that includes a directional component that is additional to a data collection directional component. The method comprises executing an initial operation step of a first operation on the first context, and subsequently commencing an execution of an initial operation step of a second operation on the first context before an execution on the first context of a following operation step of the first operation is completed. 1 to 5 bar absolute, comprising a gas phase containing residual ethylene gas to a pressure of from 2 to 20 bar absolute, absorbing the gas phase into vinyl ester, and reusing the resulting solution of ethylene in vinyl esters in a further polymerization. The fender is pivotally mounted to the support arm at a pivoting mount located above the wheel. A dross adhesion inhibitor supply flow path for feeding the dross adhesion inhibitor is connected to an assist gas feeding line in which an assist gas for assisting cutting of the object material with the plasma arc flows.