With the complexity and variety of spaces within hospitals, the air filters can play a major role in keeping the proper balancing, maintaining safe IAQ, and reducing the risk of spreading bacteria and virus throughout the building.
Here are the Minimum General Guidelines for Hospital Air Filters:
MERV-8 Prefilter and MERV-14 Final Filter, with the MERV-14 filter being the last section of the air handling equipment – Class B and C surgery, Inpaitent care, Ambulatory diagnostic, and therapeutic radilogy
MERV-8 Prefilter and HEPA Final Filter – Protective Environment Rooms
Merv-13 – Labratories and Class A surgery
Merv-8 – Administrative, bulk storage, food prep, laundry, skilled nursing, and \ outpaitent
Isolation Rooms have unique filter requirements based on the type of ISO room:
Airborne Infectious Isolation (AII) this is the most common – These rooms must maintain negative pressure to the adjoining spaces, and typically have laminar flow or some other air pattern that limits the infectious particles/spores from being transmitted, and the exhaust air must be directly ducted outdoors and is commonly HEPA filtered, HEPA filtered exhaust air is only required if the ducting merges with other ductwork.
NO anteroom is required, though highly advised
Protective Environment (PE) – These rooms must maintain positive pressure to adjoining spaces, supply air must be HEPA filtered, laminar or unidirectional airflow is not required but highly recommended, there is no requirement for the exhaust air. NO anteroom is reuired.
Combined AII/PE – These DO require an anteroom which must be the opposite pressure to the isolation room, the room with the positive pressure must have HEPA filtered supply air and the room with negative pressure must have HEPA filtered exhaust air.
Contact Isolation Room – No special pressure differential or filtration is required.