What will be the max limit of hydrogen gas flow rate (sccm) that ı should use in order not to have a dangerous situation?

Hello, I am trying to anneal graphene flake on a silica substrate at 250 celcıus degree under vacuum using a standard mechanical pump and a quartz tube. The whole process will take 4 or 5 hours...

03 March 2016 4,182 17 View