Isolated Power Systems (IPS) and Wet Locations in

The National Fire Protection Association (NFPA) Standard for Healthcare Facilities (NFPA 99) requires that wet location patient care areas be provided with “special protection against electric shock.” This paper will list the hazards associated with electric shock and the interruption of electrical power. An Isolated Power System (IPS) is one way of providing such protection, and has the inherent advantage of not requiring an interruption of the power supply should a phase-to-fault condition occur. This paper explains the design principles and requirements behind an IPS and a Ground Fault Circuit Interrupters (GFCI) and the components they use, and why an IPS is advantageous versus a GFCI at minimizing the hazard of electric shock. A brief discussion of regulatory requirements and inconsistencies therein, is also given with regard to the definition of “wet location”. Finally, an analysis of the cost implications of GFCI devices versus isolated power systems is given.