How to determine Hygienic Zones

Hello Everyone,

I was told by a colleague that in Processing areas less than 20,000 sqft Zone 3 sites are to be treated at Zone 2 sites.  Is this true?  If so, where can I find the documented source?  My Plant Manager wants written confirmation.

Thanks in advance

I suspect this information is coming from the FDA Investigations Operations Manual.  However, maybe the interpretation is slightly incorrect.  In Chapter 4 (page 135-136), the environmental zones are defined.  The Zone 2 definition makes reference to 20,000 sq. ft. as an example for a larger processing area, but I think some folks have taken this number and tried to make it a hard rule.  It is important to read the full definition for all zones and make the best decision based on your processes and traffic patterns.