Compressor Room Controls - Glass Manufacturing Facility

I have looked through all the standards and guidelines for food safety in a packaging material manufacturing however I am not seeing any specifics with regards to compressor room separation - does it need to be separated from the manufacturing floor via wall and door or can an air curtain work?

I am QA in a food safety packaging manufacturing plant and I don't believe we have either, they are just tucked in our maintenance department which is away from the lines but still open (no door, curtain, wall, etc). We are SQF level 3 and have not had a complaint thus far.