Controlling the gases arising from the use of oxygen and acetylene, consisting mainly of carbon dioxide with the addition of oxides of nitrogen where an oxidising flame is used, and carbon monoxide.

The bonding together of two pieces of metal, the joint being created by a layer of molten alloy, the flow of which is assisted by a flux.

The creation of a joint between the faces of sheet metal components or between wires and terminals using molten solder with a flux. 

Turning: The production by turning, facing, boring, screw cutting, centre drilling and knurling of primarily cylindrical or spherical forms from both ferrous and non-ferrous raw material, or appropriate plastics possibly using oil-based coolants.