HVAC - Clean rooms?

Hi. I've got a big problem. I recently graduated in mechanical engineering, and joined a Medical device manufacturin company.

I wish to know, what are the requirements of a Medical device clean room facility - ISO class 10,000 and 100,000. CFM, FPM, and other specifications.
We've hired a professional consultant, but since i'm still a trainee, and this does not come under my job profile, i am unable to approach him directly. He stays out of town, and comes over once a month. Rest everything is either over phone or email.

How to calculate duct sizing? How to select the right AHU.

i don't want to design any of it. I just want to understand how to get the maximum out of the consultant, to be able to actively participate in the process with my senior (who's not a mech engg), so i do feel a bit anxious to take charge and take over the project. Can anyone help?

Thanks.