What is Classification of Incubator Room and its Guidelines if any

What is Classification of Incubator Room and its Guidelines if any. According to me its should be Class 100000 or ISO8 or less and with Air Lock. please clarify and Share Latest guidelines.

I think no need to classify any incubation room where incubator are kept because this only provide temperature for growing microorganism hence there is a no relation outer and inner environment .

if you can give a class then not bad.