A method 3, wherein {TAIL ~ said step} of providing {HEAD ~ a flow} of gas across said opening is performed inside of said oven region adjacent said opening 
A method 3 , wherein { TAIL ~ said step } of providing { HEAD ~ a flow } of gas across said opening is performed inside of said oven region adjacent said opening
OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH