Hypobaric 1 : (Hcf-Hyp) Facility, building, or structure used to house chambers and all auxiliary service equipment for medical applications and procedures at pressures below atmospheric pressures
NFPA 99 Standard for Health Care Facilities, 2002 ed. https://law.resource.org/pub/us/cfr/ibr/004/nfpa.9 9.2005.pdf, (Std: Hlth Care Fcilty - Amer) {242 NFC}