4.3.12.1.1* Egress corridors in health care nursing and long term care facilities, detention and correctional, and
residential occupancies shall not be used as a portion of a supply, return, or exhaust air system serving adjoining
areas unless otherwise permitted by 4.3.12.1.3.1 through 4.3.12.1.3.4.
4.3.12.1.2 Air movement between rooms and egress corridors in hospitals, nursing facilities, and ambulatory
care facilities shall be permitted where the transfer of air is required for clinical purposes by other standards.
A.4.3.12.1.1 See ANSI/ASHRAE/ASHE Standard 170, Ventilation of Health Care Facilities.
Submitter’s Substantiation: The restriction to using corridors in hospitals as a portion of the supply, return or
exhaust air system was inadvertently removed from the wording in the 2012 Edition of NFPA 90A. The new
wording in NFPA 90A will allow hospitals to use the corridor as a return air plenum. If the corridor is used as a
return air plenum, smoke from a fire would be drawn into the corridor by design, creating a hazard by
compromising the corridor from being used as an egress path. The use of the corridor as part of the supply,
return or exhaust air system was explicitly restricted in hospitals in the 2009 edition of the standard and the
modifications proposed by this TIA will again restrict corridors in hospitals from being used as part of the air
system.