Substrate loading device including a frame adapted to connect the substrate loading device to a substrate processing apparatus, the frame having a transport opening through which substrates are transported between the substrate loading device and the substrate processing apparatus, a cassette support connected to the frame for holding at least one substrate cassette container for transfer of substrates to and from the at least one substrate cassette container through the transport opening, and selectably variable cassette support purge ports with a variable purge port nozzle outlet, variable between more than one selectable predetermined purge port nozzle characteristics, disposed on the cassette support, each of the more than one purge port nozzle characteristics being configured so that the purge port nozzle outlet with each selected predetermined purge port nozzle characteristic complements and couples to at least one purge port of the at least one substrate cassette container.