We are installing an air curtain for insect control only for food defense of our SQF system. It is a receiving door that is actually inside. The hallway is common area to other tenants in the building. Any thoughts on inside or outside mounting? Outside would be easier and is ok with the building management. Also, the installer asked if we needed our curtain to be NSF (national Sanitation Foundation) certified (??) I had never even heard of NSF, so not sure at this time. Maybe that is a question for our local health dept?