The loss of normal power at a medical facility, whether the result of a natural disaster or system failure, is a situation that every health care engineer must anticipate. Certain hvac equipment is required by the National Electric Code or mandated by the authority having jurisdiction (AHJ) to be connected to the emergency power system of a hospital. Hvac systems that are not code required or mandated for connection to the emergency power system may still need to operate to meet the facility's needs during a number of critical situations.
Performing a hazard vulnerability analysis as outlined by the Joint Commission on Accreditation of Healthcare Organizations (JCAHO) is the best way to begin to establish the extent of the hvac emergency power requirements that are above the minimum required by code or otherwise mandated. The first step, however, is to understand the code requirements.