These requirements in this standard cover the individual unitsand equipment that operate within the context of a fundamental hospital signaling nurse call system (NCS). A fundamental NCS provides audible and visual communication between patients and staff in a health care facility and conforms to the minimum requirements established in the Health Care Facilities Code@ NFPA 99@ and the National Electrical Code@ NFPA 70. Miscellaneous signaling equipment not intended to perform fundamental operation@ such as bedside tables@ bed exit devices@ annunciators@ gas monitoring units. and other similar types of equipment may be evaluated for compliance with applicable requirements described in this standard. The units comprising a fundamental NCS covered by this standard are intended to be installed in patient care areas@ staff areas@ and support areas of a health care facility in accordance with the National Electrical Code@ NFPA 70@ and the Health Care Facilities Code@ NFPA 99. These requirements do not cover medical and dental equipment@ line isolation monitors@ X-ray equipment@ electrically heated pads@ therapeutic lamps@ refrigerated oxygen therapy equipment@ food warming cabinets and carts@ equipment employed in inhalation anesthetizing or hazardous locations@ office intercoms@ or similar equipment and products covered by individual requirements. These requirements do not cover equipment employed in an area of hyperbaric oxygenation@ in which a patient is exposed during oxygen therapy to pressures greater than ambient atmosphere.