In a recent Q&A on the FacilityCare website, consultant Brad Keyes answered a question about ventilation-check frequency.
Q: Is there a code or standard that states how frequently the tests must be conducted for air-exchange rates and air-pressure relationships in operating rooms, soiled utility rooms and central sterile supply clean rooms?
A: Different authorities having jurisdiction (AHJ) may follow specific standards that address the frequency of air-pressure checks and air-exchange rates but, generally speaking, I am not aware of a specific code or standard that addresses this on a national level.
My best advice for you is to contact all your AHJs and ask them how frequently they expect you to test these ventilation requirements.
Ventilation and Filtering for Infection Control 
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